* [PATCH 6/9] dwarf2cfi: Convert queued_reg_save to a VEC.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
@ 2011-07-14 23:10 ` Richard Henderson
2011-07-14 23:10 ` [PATCH 3/9] dwarf2cfi: Populate CUR_ROW->REG_SAVE Richard Henderson
` (9 subsequent siblings)
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:10 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
Also, allocate it in the heap instead of garbage collected.
---
gcc/dwarf2cfi.c | 51 ++++++++++++++++++++++++++-------------------------
1 files changed, 26 insertions(+), 25 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index 51fb824..a800cb4 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -1091,14 +1091,16 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
of the prologue or (b) the register is clobbered. This clusters
register saves so that there are fewer pc advances. */
-struct GTY(()) queued_reg_save {
- struct queued_reg_save *next;
+typedef struct {
rtx reg;
- HOST_WIDE_INT cfa_offset;
rtx saved_reg;
-};
+ HOST_WIDE_INT cfa_offset;
+} queued_reg_save;
-static GTY(()) struct queued_reg_save *queued_reg_saves;
+DEF_VEC_O (queued_reg_save);
+DEF_VEC_ALLOC_O (queued_reg_save, heap);
+
+static VEC(queued_reg_save, heap) *queued_reg_saves;
/* The caller's ORIG_REG is saved in SAVED_IN_REG. */
typedef struct GTY(()) reg_saved_in_data {
@@ -1170,24 +1172,21 @@ record_reg_saved_in_reg (rtx dest, rtx src)
static void
queue_reg_save (rtx reg, rtx sreg, HOST_WIDE_INT offset)
{
- struct queued_reg_save *q;
+ queued_reg_save *q;
+ size_t i;
/* Duplicates waste space, but it's also necessary to remove them
for correctness, since the queue gets output in reverse order. */
- for (q = queued_reg_saves; q != NULL; q = q->next)
+ FOR_EACH_VEC_ELT (queued_reg_save, queued_reg_saves, i, q)
if (compare_reg_or_pc (q->reg, reg))
- break;
+ goto found;
- if (q == NULL)
- {
- q = ggc_alloc_queued_reg_save ();
- q->next = queued_reg_saves;
- queued_reg_saves = q;
- }
+ q = VEC_safe_push (queued_reg_save, heap, queued_reg_saves, NULL);
+ found:
q->reg = reg;
- q->cfa_offset = offset;
q->saved_reg = sreg;
+ q->cfa_offset = offset;
}
/* Output all the entries in QUEUED_REG_SAVES. */
@@ -1195,9 +1194,10 @@ queue_reg_save (rtx reg, rtx sreg, HOST_WIDE_INT offset)
static void
dwarf2out_flush_queued_reg_saves (void)
{
- struct queued_reg_save *q;
+ queued_reg_save *q;
+ size_t i;
- for (q = queued_reg_saves; q; q = q->next)
+ FOR_EACH_VEC_ELT (queued_reg_save, queued_reg_saves, i, q)
{
unsigned int reg, sreg;
@@ -1214,7 +1214,7 @@ dwarf2out_flush_queued_reg_saves (void)
reg_save (reg, sreg, q->cfa_offset);
}
- queued_reg_saves = NULL;
+ VEC_truncate (queued_reg_save, queued_reg_saves, 0);
}
/* Does INSN clobber any register which QUEUED_REG_SAVES lists a saved
@@ -1225,17 +1225,18 @@ dwarf2out_flush_queued_reg_saves (void)
static bool
clobbers_queued_reg_save (const_rtx insn)
{
- struct queued_reg_save *q;
+ queued_reg_save *q;
+ size_t iq;
- for (q = queued_reg_saves; q; q = q->next)
+ FOR_EACH_VEC_ELT (queued_reg_save, queued_reg_saves, iq, q)
{
- size_t i;
+ size_t ir;
reg_saved_in_data *rir;
if (modified_in_p (q->reg, insn))
return true;
- FOR_EACH_VEC_ELT (reg_saved_in_data, regs_saved_in_regs, i, rir)
+ FOR_EACH_VEC_ELT (reg_saved_in_data, regs_saved_in_regs, ir, rir)
if (compare_reg_or_pc (q->reg, rir->orig_reg)
&& modified_in_p (rir->saved_in_reg, insn))
return true;
@@ -1250,11 +1251,11 @@ static rtx
reg_saved_in (rtx reg)
{
unsigned int regn = REGNO (reg);
- struct queued_reg_save *q;
+ queued_reg_save *q;
reg_saved_in_data *rir;
size_t i;
- for (q = queued_reg_saves; q; q = q->next)
+ FOR_EACH_VEC_ELT (queued_reg_save, queued_reg_saves, i, q)
if (q->saved_reg && regn == REGNO (q->saved_reg))
return q->reg;
@@ -2770,7 +2771,7 @@ execute_dwarf2_frame (void)
XDELETEVEC (barrier_args_size);
barrier_args_size = NULL;
regs_saved_in_regs = NULL;
- queued_reg_saves = NULL;
+ VEC_free (queued_reg_save, heap, queued_reg_saves);
free_cfi_row (cur_row);
cur_row = NULL;
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* [PATCH 3/9] dwarf2cfi: Populate CUR_ROW->REG_SAVE.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
2011-07-14 23:10 ` [PATCH 6/9] dwarf2cfi: Convert queued_reg_save to a VEC Richard Henderson
@ 2011-07-14 23:10 ` Richard Henderson
2011-07-14 23:10 ` [PATCH 1/9] dwarf2cfi: Introduce a dw_cfi_row state Richard Henderson
` (8 subsequent siblings)
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:10 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
To be actually used by a subsequent patch.
---
gcc/dwarf2cfi.c | 27 +++++++++++++++++++++++++--
1 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index eb59f28..36fa7f8 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -285,6 +285,17 @@ add_cfi (dw_cfi_ref cfi)
VEC_safe_push (dw_cfi_ref, gc, *add_cfi_vec, cfi);
}
+/* Perform ROW->REG_SAVE[COLUMN] = CFI. CFI may be null, indicating
+ that the register column is no longer saved. */
+
+static void
+update_row_reg_save (dw_cfi_row_ref row, unsigned column, dw_cfi_ref cfi)
+{
+ if (VEC_length (dw_cfi_ref, row->reg_save) <= column)
+ VEC_safe_grow_cleared (dw_cfi_ref, gc, row->reg_save, column + 1);
+ VEC_replace (dw_cfi_ref, row->reg_save, column, cfi);
+}
+
/* This function fills in aa dw_cfa_location structure from a dwarf location
descriptor sequence. */
@@ -574,7 +585,13 @@ reg_save (unsigned int reg, unsigned int sreg, HOST_WIDE_INT offset)
cfi->dw_cfi_oprnd2.dw_cfi_offset = offset;
}
else if (sreg == reg)
- cfi->dw_cfi_opc = DW_CFA_same_value;
+ {
+ /* While we could emit something like DW_CFA_same_value or
+ DW_CFA_restore, we never expect to see something like that
+ in a prologue. This is more likely to be a bug. A backend
+ can always bypass this by using REG_CFA_RESTORE directly. */
+ gcc_unreachable ();
+ }
else
{
cfi->dw_cfi_opc = DW_CFA_register;
@@ -582,6 +599,7 @@ reg_save (unsigned int reg, unsigned int sreg, HOST_WIDE_INT offset)
}
add_cfi (cfi);
+ update_row_reg_save (cur_row, reg, cfi);
}
/* Given a SET, calculate the amount of stack adjustment it
@@ -1337,6 +1355,7 @@ dwarf2out_frame_debug_cfa_expression (rtx set)
{
rtx src, dest, span;
dw_cfi_ref cfi = new_cfi ();
+ unsigned regno;
dest = SET_DEST (set);
src = SET_SRC (set);
@@ -1347,8 +1366,10 @@ dwarf2out_frame_debug_cfa_expression (rtx set)
span = targetm.dwarf_register_span (src);
gcc_assert (!span);
+ regno = dwf_regno (src);
+
cfi->dw_cfi_opc = DW_CFA_expression;
- cfi->dw_cfi_oprnd1.dw_cfi_reg_num = dwf_regno (src);
+ cfi->dw_cfi_oprnd1.dw_cfi_reg_num = regno;
cfi->dw_cfi_oprnd2.dw_cfi_loc
= mem_loc_descriptor (XEXP (dest, 0), get_address_mode (dest),
GET_MODE (dest), VAR_INIT_STATUS_INITIALIZED);
@@ -1356,6 +1377,7 @@ dwarf2out_frame_debug_cfa_expression (rtx set)
/* ??? We'd like to use queue_reg_save, were the interface different,
and, as above, we could manage flushing for epilogues. */
add_cfi (cfi);
+ update_row_reg_save (cur_row, regno, cfi);
}
/* A subroutine of dwarf2out_frame_debug, process a REG_CFA_RESTORE note. */
@@ -1370,6 +1392,7 @@ dwarf2out_frame_debug_cfa_restore (rtx reg)
cfi->dw_cfi_oprnd1.dw_cfi_reg_num = regno;
add_cfi (cfi);
+ update_row_reg_save (cur_row, regno, NULL);
}
/* A subroutine of dwarf2out_frame_debug, process a REG_CFA_WINDOW_SAVE.
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* [PATCH 1/9] dwarf2cfi: Introduce a dw_cfi_row state.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
2011-07-14 23:10 ` [PATCH 6/9] dwarf2cfi: Convert queued_reg_save to a VEC Richard Henderson
2011-07-14 23:10 ` [PATCH 3/9] dwarf2cfi: Populate CUR_ROW->REG_SAVE Richard Henderson
@ 2011-07-14 23:10 ` Richard Henderson
2011-07-14 23:10 ` [PATCH 8/9] dwarf2cfi: Introduce dw_trace_info Richard Henderson
` (7 subsequent siblings)
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:10 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
Use it instead of old_cfa, old_args_size, and cfa_remember variables.
Remove the global cfa variable, as it was usually a duplicate of
old_cfa and otherwise confusing. Always make a local copy of the
cur_row->cfa variable before modification instead.
---
gcc/dwarf2cfi.c | 208 +++++++++++++++++++++++++++++++++++--------------------
gcc/dwarf2out.h | 2 +-
2 files changed, 135 insertions(+), 75 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index 4e648ae..1c1b74f 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -58,9 +58,31 @@ along with GCC; see the file COPYING3. If not see
/* Maximum size (in bytes) of an artificially generated label. */
#define MAX_ARTIFICIAL_LABEL_BYTES 30
\f
+/* A collected description of an entire row of the abstract CFI table. */
+typedef struct GTY(()) dw_cfi_row_struct
+{
+ /* The expression that computes the CFA, expressed in two different ways.
+ The CFA member for the simple cases, and the full CFI expression for
+ the complex cases. The later will be a DW_CFA_cfa_expression. */
+ dw_cfa_location cfa;
+ dw_cfi_ref cfa_cfi;
+
+ /* The expressions for any register column that is saved. */
+ cfi_vec reg_save;
+
+ /* The value of any DW_CFA_GNU_args_size. */
+ HOST_WIDE_INT args_size;
+} dw_cfi_row;
+
+typedef dw_cfi_row *dw_cfi_row_ref;
+\f
/* A vector of call frame insns for the CIE. */
cfi_vec cie_cfi_vec;
+/* The state of the first row of the FDE table, which includes the
+ state provided by the CIE. */
+static GTY(()) dw_cfi_row_ref cie_cfi_row;
+
static GTY(()) unsigned long dwarf2out_cfi_label_num;
/* The insn after which a new CFI note should be emitted. */
@@ -185,6 +207,43 @@ new_cfi (void)
return cfi;
}
+/* Return a newly allocated CFI row, with no defined data. */
+
+static dw_cfi_row_ref
+new_cfi_row (void)
+{
+ dw_cfi_row_ref row = ggc_alloc_cleared_dw_cfi_row ();
+
+ row->cfa.reg = INVALID_REGNUM;
+
+ return row;
+}
+
+/* Return a copy of an existing CFI row. */
+
+static dw_cfi_row_ref
+copy_cfi_row (dw_cfi_row_ref src)
+{
+ dw_cfi_row_ref dst = ggc_alloc_dw_cfi_row ();
+
+ *dst = *src;
+ dst->reg_save = VEC_copy (dw_cfi_ref, gc, src->reg_save);
+
+ return dst;
+}
+
+/* Free an allocated CFI row. */
+
+static void
+free_cfi_row (dw_cfi_row_ref row)
+{
+ if (row != NULL)
+ {
+ VEC_free (dw_cfi_ref, gc, row->reg_save);
+ ggc_free (row);
+ }
+}
+
/* Generate a new label for the CFI info to refer to. */
static char *
@@ -371,28 +430,25 @@ lookup_cfa_1 (dw_cfi_ref cfi, dw_cfa_location *loc, dw_cfa_location *remember)
}
}
-/* The current rule for calculating the DWARF2 canonical frame address. */
-static dw_cfa_location cfa;
+/* The current, i.e. most recently generated, row of the CFI table. */
+static dw_cfi_row_ref cur_row;
-/* A copy of the CFA, for comparison purposes. */
-static dw_cfa_location old_cfa;
+/* The row state from a preceeding DW_CFA_remember_state. */
+static dw_cfi_row_ref remember_row;
/* The register used for saving registers to the stack, and its offset
from the CFA. */
static dw_cfa_location cfa_store;
-/* The current save location around an epilogue. */
-static dw_cfa_location cfa_remember;
-
-/* Like cfa_remember, but a copy of old_cfa. */
-static dw_cfa_location old_cfa_remember;
+/* A temporary register holding an integral value used in adjusting SP
+ or setting up the store_reg. The "offset" field holds the integer
+ value, not an offset. */
+static dw_cfa_location cfa_temp;
-/* The running total of the size of arguments pushed onto the stack. */
+/* The (really) current value for DW_CFA_GNU_args_size. We delay actually
+ emitting this data, i.e. updating CUR_ROW, without async unwind. */
static HOST_WIDE_INT args_size;
-/* The last args_size we actually output. */
-static HOST_WIDE_INT old_args_size;
-
/* Determine if two dw_cfa_location structures define the same data. */
bool
@@ -412,21 +468,18 @@ static void
def_cfa_1 (dw_cfa_location *loc_p)
{
dw_cfi_ref cfi;
- dw_cfa_location loc;
-
- cfa = *loc_p;
- loc = *loc_p;
+ dw_cfa_location loc = *loc_p;
if (cfa_store.reg == loc.reg && loc.indirect == 0)
cfa_store.offset = loc.offset;
/* If nothing changed, no need to issue any call frame instructions. */
- if (cfa_equal_p (&loc, &old_cfa))
+ if (cfa_equal_p (&loc, &cur_row->cfa))
return;
cfi = new_cfi ();
- if (loc.reg == old_cfa.reg && !loc.indirect && !old_cfa.indirect)
+ if (loc.reg == cur_row->cfa.reg && !loc.indirect && !cur_row->cfa.indirect)
{
/* Construct a "DW_CFA_def_cfa_offset <offset>" instruction, indicating
the CFA register did not change but the offset did. The data
@@ -440,10 +493,10 @@ def_cfa_1 (dw_cfa_location *loc_p)
}
#ifndef MIPS_DEBUGGING_INFO /* SGI dbx thinks this means no offset. */
- else if (loc.offset == old_cfa.offset
- && old_cfa.reg != INVALID_REGNUM
+ else if (loc.offset == cur_row->cfa.offset
+ && cur_row->cfa.reg != INVALID_REGNUM
&& !loc.indirect
- && !old_cfa.indirect)
+ && !cur_row->cfa.indirect)
{
/* Construct a "DW_CFA_def_cfa_register <register>" instruction,
indicating the CFA register has changed to <register> but the
@@ -477,10 +530,12 @@ def_cfa_1 (dw_cfa_location *loc_p)
cfi->dw_cfi_opc = DW_CFA_def_cfa_expression;
loc_list = build_cfa_loc (&loc, 0);
cfi->dw_cfi_oprnd1.dw_cfi_loc = loc_list;
+
+ cur_row->cfa_cfi = cfi;
}
add_cfi (cfi);
- old_cfa = loc;
+ cur_row->cfa = loc;
}
/* Add the CFI for saving a register. REG is the CFA column number.
@@ -503,7 +558,8 @@ reg_save (unsigned int reg, unsigned int sreg, HOST_WIDE_INT offset)
cfi->dw_cfi_opc = DW_CFA_expression;
cfi->dw_cfi_oprnd1.dw_cfi_reg_num = reg;
cfi->dw_cfi_oprnd2.dw_cfi_loc
- = build_cfa_aligned_loc (&cfa, offset, fde->stack_realignment);
+ = build_cfa_aligned_loc (&cur_row->cfa, offset,
+ fde->stack_realignment);
}
else if (sreg == INVALID_REGNUM)
{
@@ -797,10 +853,10 @@ dwarf2out_args_size (HOST_WIDE_INT size)
{
dw_cfi_ref cfi;
- if (size == old_args_size)
+ if (size == cur_row->args_size)
return;
- old_args_size = size;
+ cur_row->args_size = size;
cfi = new_cfi ();
cfi->dw_cfi_opc = DW_CFA_GNU_args_size;
@@ -813,12 +869,19 @@ dwarf2out_args_size (HOST_WIDE_INT size)
static void
dwarf2out_stack_adjust (HOST_WIDE_INT offset)
{
- if (cfa.reg == dw_stack_pointer_regnum)
- cfa.offset += offset;
+ dw_cfa_location loc = cur_row->cfa;
+
+ if (loc.reg == dw_stack_pointer_regnum)
+ loc.offset += offset;
if (cfa_store.reg == dw_stack_pointer_regnum)
cfa_store.offset += offset;
+ /* ??? The assumption seems to be that if A_O_A, the only CFA adjustments
+ involving the stack pointer are inside the prologue and marked as
+ RTX_FRAME_RELATED_P. That said, should we not verify this assumption
+ by *asserting* A_O_A at this point? Why else would we have a change
+ to the stack pointer? */
if (ACCUMULATE_OUTGOING_ARGS)
return;
@@ -830,7 +893,7 @@ dwarf2out_stack_adjust (HOST_WIDE_INT offset)
if (args_size < 0)
args_size = 0;
- def_cfa_1 (&cfa);
+ def_cfa_1 (&loc);
if (flag_asynchronous_unwind_tables)
dwarf2out_args_size (args_size);
}
@@ -862,7 +925,8 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
/* If only calls can throw, and we have a frame pointer,
save up adjustments until we see the CALL_INSN. */
- if (!flag_asynchronous_unwind_tables && cfa.reg != dw_stack_pointer_regnum)
+ if (!flag_asynchronous_unwind_tables
+ && cur_row->cfa.reg != dw_stack_pointer_regnum)
{
if (CALL_P (insn) && !after_p)
{
@@ -1103,39 +1167,35 @@ reg_saved_in (rtx reg)
return NULL_RTX;
}
-
-/* A temporary register holding an integral value used in adjusting SP
- or setting up the store_reg. The "offset" field holds the integer
- value, not an offset. */
-static dw_cfa_location cfa_temp;
-
/* A subroutine of dwarf2out_frame_debug, process a REG_DEF_CFA note. */
static void
dwarf2out_frame_debug_def_cfa (rtx pat)
{
- memset (&cfa, 0, sizeof (cfa));
+ dw_cfa_location loc;
+
+ memset (&loc, 0, sizeof (loc));
switch (GET_CODE (pat))
{
case PLUS:
- cfa.reg = dwf_regno (XEXP (pat, 0));
- cfa.offset = INTVAL (XEXP (pat, 1));
+ loc.reg = dwf_regno (XEXP (pat, 0));
+ loc.offset = INTVAL (XEXP (pat, 1));
break;
case REG:
- cfa.reg = dwf_regno (pat);
+ loc.reg = dwf_regno (pat);
break;
case MEM:
- cfa.indirect = 1;
+ loc.indirect = 1;
pat = XEXP (pat, 0);
if (GET_CODE (pat) == PLUS)
{
- cfa.base_offset = INTVAL (XEXP (pat, 1));
+ loc.base_offset = INTVAL (XEXP (pat, 1));
pat = XEXP (pat, 0);
}
- cfa.reg = dwf_regno (pat);
+ loc.reg = dwf_regno (pat);
break;
default:
@@ -1143,7 +1203,7 @@ dwarf2out_frame_debug_def_cfa (rtx pat)
gcc_unreachable ();
}
- def_cfa_1 (&cfa);
+ def_cfa_1 (&loc);
}
/* A subroutine of dwarf2out_frame_debug, process a REG_ADJUST_CFA note. */
@@ -1151,6 +1211,7 @@ dwarf2out_frame_debug_def_cfa (rtx pat)
static void
dwarf2out_frame_debug_adjust_cfa (rtx pat)
{
+ dw_cfa_location loc = cur_row->cfa;
rtx src, dest;
gcc_assert (GET_CODE (pat) == SET);
@@ -1160,8 +1221,8 @@ dwarf2out_frame_debug_adjust_cfa (rtx pat)
switch (GET_CODE (src))
{
case PLUS:
- gcc_assert (dwf_regno (XEXP (src, 0)) == cfa.reg);
- cfa.offset -= INTVAL (XEXP (src, 1));
+ gcc_assert (dwf_regno (XEXP (src, 0)) == loc.reg);
+ loc.offset -= INTVAL (XEXP (src, 1));
break;
case REG:
@@ -1171,10 +1232,10 @@ dwarf2out_frame_debug_adjust_cfa (rtx pat)
gcc_unreachable ();
}
- cfa.reg = dwf_regno (dest);
- gcc_assert (cfa.indirect == 0);
+ loc.reg = dwf_regno (dest);
+ gcc_assert (loc.indirect == 0);
- def_cfa_1 (&cfa);
+ def_cfa_1 (&loc);
}
/* A subroutine of dwarf2out_frame_debug, process a REG_CFA_OFFSET note. */
@@ -1195,12 +1256,12 @@ dwarf2out_frame_debug_cfa_offset (rtx set)
switch (GET_CODE (addr))
{
case REG:
- gcc_assert (dwf_regno (addr) == cfa.reg);
- offset = -cfa.offset;
+ gcc_assert (dwf_regno (addr) == cur_row->cfa.reg);
+ offset = -cur_row->cfa.offset;
break;
case PLUS:
- gcc_assert (dwf_regno (XEXP (addr, 0)) == cfa.reg);
- offset = INTVAL (XEXP (addr, 1)) - cfa.offset;
+ gcc_assert (dwf_regno (XEXP (addr, 0)) == cur_row->cfa.reg);
+ offset = INTVAL (XEXP (addr, 1)) - cur_row->cfa.offset;
break;
default:
gcc_unreachable ();
@@ -1366,7 +1427,9 @@ dwarf2out_frame_debug_cfa_window_save (void)
Invariants / Summaries of Rules
cfa current rule for calculating the CFA. It usually
- consists of a register and an offset.
+ consists of a register and an offset. This is
+ actually stored in cur_row->cfa, but abbreviated
+ for the purposes of this documentation.
cfa_store register used by prologue code to save things to the stack
cfa_store.offset is the offset from the value of
cfa_store.reg to the actual CFA
@@ -1520,6 +1583,7 @@ dwarf2out_frame_debug_cfa_window_save (void)
static void
dwarf2out_frame_debug_expr (rtx expr)
{
+ dw_cfa_location cfa = cur_row->cfa;
rtx src, dest, span;
HOST_WIDE_INT offset;
dw_fde_ref fde;
@@ -2391,10 +2455,8 @@ dwarf2out_cfi_begin_epilogue (rtx insn)
emit_cfa_remember = true;
/* And emulate the state save. */
- gcc_assert (!cfa_remember.in_use);
- cfa_remember = cfa;
- old_cfa_remember = old_cfa;
- cfa_remember.in_use = 1;
+ gcc_assert (remember_row == NULL);
+ remember_row = copy_cfi_row (cur_row);
}
/* A "subroutine" of dwarf2out_cfi_begin_epilogue. Emit the restore
@@ -2408,10 +2470,10 @@ dwarf2out_frame_debug_restore_state (void)
cfi->dw_cfi_opc = DW_CFA_restore_state;
add_cfi (cfi);
- gcc_assert (cfa_remember.in_use);
- cfa = cfa_remember;
- old_cfa = old_cfa_remember;
- cfa_remember.in_use = 0;
+ gcc_assert (remember_row != NULL);
+ free_cfi_row (cur_row);
+ cur_row = remember_row;
+ remember_row = NULL;
}
\f
/* Record the initial position of the return address. RTL is
@@ -2472,7 +2534,7 @@ initial_return_save (rtx rtl)
{
if (reg != INVALID_REGNUM)
record_reg_saved_in_reg (rtl, pc_rtx);
- reg_save (DWARF_FRAME_RETURN_COLUMN, reg, offset - cfa.offset);
+ reg_save (DWARF_FRAME_RETURN_COLUMN, reg, offset - cur_row->cfa.offset);
}
}
@@ -2492,9 +2554,7 @@ execute_dwarf2_frame (void)
dw_frame_pointer_regnum = DWARF_FRAME_REGNUM (HARD_FRAME_POINTER_REGNUM);
add_cfi_vec = &cie_cfi_vec;
-
- memset (&old_cfa, 0, sizeof (old_cfa));
- old_cfa.reg = INVALID_REGNUM;
+ cie_cfi_row = cur_row = new_cfi_row ();
/* On entry, the Canonical Frame Address is at SP. */
memset(&loc, 0, sizeof (loc));
@@ -2537,19 +2597,16 @@ execute_dwarf2_frame (void)
gcc_checking_assert (queued_reg_saves == NULL);
gcc_checking_assert (regs_saved_in_regs == NULL);
- memset (&cfa, 0, sizeof(cfa));
- cfa.reg = dw_stack_pointer_regnum;
- cfa.offset = INCOMING_FRAME_SP_OFFSET;
+ cur_row = copy_cfi_row (cie_cfi_row);
+ if (cie_return_save)
+ VEC_safe_push (reg_saved_in_data, gc, regs_saved_in_regs, cie_return_save);
- old_cfa = cfa;
- cfa_store = cfa;
+ cfa_store = cur_row->cfa;
+ args_size = 0;
memset (&cfa_temp, 0, sizeof(cfa_temp));
cfa_temp.reg = INVALID_REGNUM;
- if (cie_return_save)
- VEC_safe_push (reg_saved_in_data, gc, regs_saved_in_regs, cie_return_save);
-
dwarf2out_alloc_current_fde ();
/* Do the work. */
@@ -2562,6 +2619,9 @@ execute_dwarf2_frame (void)
regs_saved_in_regs = NULL;
queued_reg_saves = NULL;
+ free_cfi_row (cur_row);
+ cur_row = NULL;
+
return 0;
}
\f
diff --git a/gcc/dwarf2out.h b/gcc/dwarf2out.h
index 3013211..d0e76a7 100644
--- a/gcc/dwarf2out.h
+++ b/gcc/dwarf2out.h
@@ -118,7 +118,7 @@ dw_fde_node;
It can now be either REG + CFA_OFFSET or *(REG + BASE_OFFSET) + CFA_OFFSET.
Instead of passing around REG and OFFSET, we pass a copy
of this structure. */
-typedef struct cfa_loc {
+typedef struct GTY(()) cfa_loc {
HOST_WIDE_INT offset;
HOST_WIDE_INT base_offset;
/* REG is in DWARF_FRAME_REGNUM space, *not* normal REGNO space. */
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* [PATCH 8/9] dwarf2cfi: Introduce dw_trace_info.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (2 preceding siblings ...)
2011-07-14 23:10 ` [PATCH 1/9] dwarf2cfi: Introduce a dw_cfi_row state Richard Henderson
@ 2011-07-14 23:10 ` Richard Henderson
2011-07-14 23:10 ` [PATCH 4/9] dwarf2cfi: Implement change_cfi_row Richard Henderson
` (6 subsequent siblings)
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:10 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
This patch only introduces the structure definition and adjusts
the existing routines to use the new cur_trace global to access
the variables that were moved into the structure.
---
gcc/dwarf2cfi.c | 440 +++++++++++++++++++++++++++++++++----------------------
1 files changed, 266 insertions(+), 174 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index 1d6413f..9aa1208 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -74,7 +74,98 @@ typedef struct GTY(()) dw_cfi_row_struct
HOST_WIDE_INT args_size;
} dw_cfi_row;
-\f
+/* The caller's ORIG_REG is saved in SAVED_IN_REG. */
+typedef struct GTY(()) reg_saved_in_data_struct {
+ rtx orig_reg;
+ rtx saved_in_reg;
+} reg_saved_in_data;
+
+DEF_VEC_O (reg_saved_in_data);
+DEF_VEC_ALLOC_O (reg_saved_in_data, heap);
+
+/* Since we no longer have a proper CFG, we're going to create a facsimile
+ of one on the fly while processing the frame-related insns.
+
+ We create dw_trace structures for each instruction trace beginning at
+ at a label following a barrier (or beginning of the function), and
+ ending at a barrier (or the end of the function).
+
+ As we encounter control transfer insns, we propagate the "current"
+ row state across the edges to the starts of traces. If an edge goes
+ to a label that is not the start of a trace, we ignore it. This
+ assumes that previous compiler transformations were correct, and that
+ we will reach the same row state from any source. (We can perform some
+ limited validation of this assumption, but without the full CFG we
+ cannot be sure of full validation coverage. It is expensive, so we
+ only do so with checking enabled.)
+
+ All traces are members of the TRACE_INFO array, in the order in which
+ they appear in the instruction stream.
+
+ All labels are given an LUID that indexes the LABEL_INFO array. If
+ the label is the start of a trace, the TRACE pointer will be non-NULL
+ and point into the TRACE_INFO array. */
+
+typedef struct
+{
+ /* The label that begins the trace. This will be NULL for the first
+ trace beginning at function entry. */
+ rtx label;
+
+ /* The row state at the beginning and end of the trace. */
+ dw_cfi_row *enter_row, *exit_row;
+
+ /* The following variables contain data used in interpreting frame related
+ expressions. These are not part of the "real" row state as defined by
+ Dwarf, but it seems like they need to be propagated into a trace in case
+ frame related expressions have been sunk. */
+ /* ??? This seems fragile. These variables are fragments of a larger
+ expression. If we do not keep the entire expression together, we risk
+ not being able to put it together properly. Consider forcing targets
+ to generate self-contained expressions and dropping all of the magic
+ interpretation code in this file. Or at least refusing to shrink wrap
+ any frame related insn that doesn't contain a complete expression. */
+
+ /* The register used for saving registers to the stack, and its offset
+ from the CFA. */
+ dw_cfa_location cfa_store;
+
+ /* A temporary register holding an integral value used in adjusting SP
+ or setting up the store_reg. The "offset" field holds the integer
+ value, not an offset. */
+ dw_cfa_location cfa_temp;
+
+ /* A set of registers saved in other registers. This is the inverse of
+ the row->reg_save info, if the entry is a DW_CFA_register. This is
+ implemented as a flat array because it normally contains zero or 1
+ entry, depending on the target. IA-64 is the big spender here, using
+ a maximum of 5 entries. */
+ VEC(reg_saved_in_data, heap) *regs_saved_in_regs;
+
+} dw_trace_info;
+
+DEF_VEC_O (dw_trace_info);
+DEF_VEC_ALLOC_O (dw_trace_info, heap);
+
+typedef struct
+{
+ dw_trace_info *trace;
+
+#ifdef ENABLE_CHECKING
+ dw_cfi_row *check_row;
+#endif
+} dw_label_info;
+
+DEF_VEC_O (dw_label_info);
+DEF_VEC_ALLOC_O (dw_label_info, heap);
+
+/* The variables making up the pseudo-cfg, as described above. */
+#if 0
+static VEC (int, heap) *uid_luid;
+static VEC (dw_label_info, heap) *label_info;
+static VEC (dw_trace_info, heap) *trace_info;
+#endif
+
/* A vector of call frame insns for the CIE. */
cfi_vec cie_cfi_vec;
@@ -82,6 +173,8 @@ cfi_vec cie_cfi_vec;
state provided by the CIE. */
static GTY(()) dw_cfi_row *cie_cfi_row;
+static GTY(()) reg_saved_in_data *cie_return_save;
+
static GTY(()) unsigned long dwarf2out_cfi_label_num;
/* The insn after which a new CFI note should be emitted. */
@@ -90,6 +183,34 @@ static rtx add_cfi_insn;
/* When non-null, add_cfi will add the CFI to this vector. */
static cfi_vec *add_cfi_vec;
+/* The current instruction trace. */
+static dw_trace_info *cur_trace;
+
+/* The current, i.e. most recently generated, row of the CFI table. */
+static dw_cfi_row *cur_row;
+
+/* The row state from a preceeding DW_CFA_remember_state. */
+static dw_cfi_row *remember_row;
+
+/* We delay emitting a register save until either (a) we reach the end
+ of the prologue or (b) the register is clobbered. This clusters
+ register saves so that there are fewer pc advances. */
+
+typedef struct {
+ rtx reg;
+ rtx saved_reg;
+ HOST_WIDE_INT cfa_offset;
+} queued_reg_save;
+
+DEF_VEC_O (queued_reg_save);
+DEF_VEC_ALLOC_O (queued_reg_save, heap);
+
+static VEC(queued_reg_save, heap) *queued_reg_saves;
+
+/* The (really) current value for DW_CFA_GNU_args_size. We delay actually
+ emitting this data, i.e. updating CUR_ROW, without async unwind. */
+static HOST_WIDE_INT queued_args_size;
+
/* True if remember_state should be emitted before following CFI directive. */
static bool emit_cfa_remember;
@@ -464,25 +585,6 @@ lookup_cfa_1 (dw_cfi_ref cfi, dw_cfa_location *loc, dw_cfa_location *remember)
}
}
-/* The current, i.e. most recently generated, row of the CFI table. */
-static dw_cfi_row *cur_row;
-
-/* The row state from a preceeding DW_CFA_remember_state. */
-static dw_cfi_row *remember_row;
-
-/* The register used for saving registers to the stack, and its offset
- from the CFA. */
-static dw_cfa_location cfa_store;
-
-/* A temporary register holding an integral value used in adjusting SP
- or setting up the store_reg. The "offset" field holds the integer
- value, not an offset. */
-static dw_cfa_location cfa_temp;
-
-/* The (really) current value for DW_CFA_GNU_args_size. We delay actually
- emitting this data, i.e. updating CUR_ROW, without async unwind. */
-static HOST_WIDE_INT args_size;
-
/* Determine if two dw_cfa_location structures define the same data. */
bool
@@ -621,8 +723,8 @@ def_cfa_1 (dw_cfa_location *new_cfa)
{
dw_cfi_ref cfi;
- if (cfa_store.reg == new_cfa->reg && new_cfa->indirect == 0)
- cfa_store.offset = new_cfa->offset;
+ if (cur_trace->cfa_store.reg == new_cfa->reg && new_cfa->indirect == 0)
+ cur_trace->cfa_store.offset = new_cfa->offset;
cfi = def_cfa_0 (&cur_row->cfa, new_cfa);
if (cfi)
@@ -972,8 +1074,16 @@ dwarf2out_stack_adjust (HOST_WIDE_INT offset)
if (loc.reg == dw_stack_pointer_regnum)
loc.offset += offset;
- if (cfa_store.reg == dw_stack_pointer_regnum)
- cfa_store.offset += offset;
+ if (cur_trace->cfa_store.reg == dw_stack_pointer_regnum)
+ cur_trace->cfa_store.offset += offset;
+
+#ifndef STACK_GROWS_DOWNWARD
+ offset = -offset;
+#endif
+
+ queued_args_size += offset;
+ if (queued_args_size < 0)
+ queued_args_size = 0;
/* ??? The assumption seems to be that if A_O_A, the only CFA adjustments
involving the stack pointer are inside the prologue and marked as
@@ -983,17 +1093,9 @@ dwarf2out_stack_adjust (HOST_WIDE_INT offset)
if (ACCUMULATE_OUTGOING_ARGS)
return;
-#ifndef STACK_GROWS_DOWNWARD
- offset = -offset;
-#endif
-
- args_size += offset;
- if (args_size < 0)
- args_size = 0;
-
def_cfa_1 (&loc);
if (flag_asynchronous_unwind_tables)
- dwarf2out_args_size (args_size);
+ dwarf2out_args_size (queued_args_size);
}
/* Check INSN to see if it looks like a push or a stack adjustment, and
@@ -1035,7 +1137,8 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
if (GET_CODE (insn) == SET)
insn = SET_SRC (insn);
gcc_assert (GET_CODE (insn) == CALL);
- dwarf2out_args_size (INTVAL (XEXP (insn, 1)));
+ gcc_assert (queued_args_size == INTVAL (XEXP (insn, 1)));
+ dwarf2out_args_size (queued_args_size);
}
return;
}
@@ -1043,7 +1146,7 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
if (CALL_P (insn) && !after_p)
{
if (!flag_asynchronous_unwind_tables)
- dwarf2out_args_size (args_size);
+ dwarf2out_args_size (queued_args_size);
return;
}
else if (BARRIER_P (insn))
@@ -1061,13 +1164,13 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
offset = 0;
}
- offset -= args_size;
+ offset -= queued_args_size;
#ifndef STACK_GROWS_DOWNWARD
offset = -offset;
#endif
}
else if (GET_CODE (PATTERN (insn)) == SET)
- offset = stack_adjust_offset (PATTERN (insn), args_size, 0);
+ offset = stack_adjust_offset (PATTERN (insn), queued_args_size, 0);
else if (GET_CODE (PATTERN (insn)) == PARALLEL
|| GET_CODE (PATTERN (insn)) == SEQUENCE)
{
@@ -1076,7 +1179,7 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
for (offset = 0, i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
if (GET_CODE (XVECEXP (PATTERN (insn), 0, i)) == SET)
offset += stack_adjust_offset (XVECEXP (PATTERN (insn), 0, i),
- args_size, offset);
+ queued_args_size, offset);
}
else
return;
@@ -1087,38 +1190,6 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
dwarf2out_stack_adjust (offset);
}
-/* We delay emitting a register save until either (a) we reach the end
- of the prologue or (b) the register is clobbered. This clusters
- register saves so that there are fewer pc advances. */
-
-typedef struct {
- rtx reg;
- rtx saved_reg;
- HOST_WIDE_INT cfa_offset;
-} queued_reg_save;
-
-DEF_VEC_O (queued_reg_save);
-DEF_VEC_ALLOC_O (queued_reg_save, heap);
-
-static VEC(queued_reg_save, heap) *queued_reg_saves;
-
-/* The caller's ORIG_REG is saved in SAVED_IN_REG. */
-typedef struct GTY(()) reg_saved_in_data {
- rtx orig_reg;
- rtx saved_in_reg;
-} reg_saved_in_data;
-
-DEF_VEC_O (reg_saved_in_data);
-DEF_VEC_ALLOC_O (reg_saved_in_data, heap);
-
-/* A set of registers saved in other registers. This is implemented as
- a flat array because it normally contains zero or 1 entry, depending
- on the target. IA-64 is the big spender here, using a maximum of
- 5 entries. */
-static VEC(reg_saved_in_data, heap) *regs_saved_in_regs;
-
-static GTY(()) reg_saved_in_data *cie_return_save;
-
/* Short-hand inline for the very common D_F_R (REGNO (x)) operation. */
/* ??? This ought to go into dwarf2out.h, except that dwarf2out.h is
used in places where rtl is prohibited. */
@@ -1148,11 +1219,12 @@ record_reg_saved_in_reg (rtx dest, rtx src)
reg_saved_in_data *elt;
size_t i;
- FOR_EACH_VEC_ELT (reg_saved_in_data, regs_saved_in_regs, i, elt)
+ FOR_EACH_VEC_ELT (reg_saved_in_data, cur_trace->regs_saved_in_regs, i, elt)
if (compare_reg_or_pc (elt->orig_reg, src))
{
if (dest == NULL)
- VEC_unordered_remove(reg_saved_in_data, regs_saved_in_regs, i);
+ VEC_unordered_remove (reg_saved_in_data,
+ cur_trace->regs_saved_in_regs, i);
else
elt->saved_in_reg = dest;
return;
@@ -1161,7 +1233,8 @@ record_reg_saved_in_reg (rtx dest, rtx src)
if (dest == NULL)
return;
- elt = VEC_safe_push(reg_saved_in_data, heap, regs_saved_in_regs, NULL);
+ elt = VEC_safe_push (reg_saved_in_data, heap,
+ cur_trace->regs_saved_in_regs, NULL);
elt->orig_reg = src;
elt->saved_in_reg = dest;
}
@@ -1236,7 +1309,8 @@ clobbers_queued_reg_save (const_rtx insn)
if (modified_in_p (q->reg, insn))
return true;
- FOR_EACH_VEC_ELT (reg_saved_in_data, regs_saved_in_regs, ir, rir)
+ FOR_EACH_VEC_ELT (reg_saved_in_data,
+ cur_trace->regs_saved_in_regs, ir, rir)
if (compare_reg_or_pc (q->reg, rir->orig_reg)
&& modified_in_p (rir->saved_in_reg, insn))
return true;
@@ -1259,7 +1333,7 @@ reg_saved_in (rtx reg)
if (q->saved_reg && regn == REGNO (q->saved_reg))
return q->reg;
- FOR_EACH_VEC_ELT (reg_saved_in_data, regs_saved_in_regs, i, rir)
+ FOR_EACH_VEC_ELT (reg_saved_in_data, cur_trace->regs_saved_in_regs, i, rir)
if (regn == REGNO (rir->saved_in_reg))
return rir->orig_reg;
@@ -1371,7 +1445,7 @@ dwarf2out_frame_debug_cfa_offset (rtx set)
span = NULL;
sregno = DWARF_FRAME_RETURN_COLUMN;
}
- else
+ else
{
span = targetm.dwarf_register_span (src);
sregno = dwf_regno (src);
@@ -1727,7 +1801,8 @@ dwarf2out_frame_debug_expr (rtx expr)
{
/* Stack adjustment combining might combine some post-prologue
stack adjustment into a prologue stack adjustment. */
- HOST_WIDE_INT offset = stack_adjust_offset (elem, args_size, 0);
+ HOST_WIDE_INT offset
+ = stack_adjust_offset (elem, queued_args_size, 0);
if (offset != 0)
dwarf2out_stack_adjust (offset);
@@ -1768,8 +1843,8 @@ dwarf2out_frame_debug_expr (rtx expr)
FP. So we just rely on the backends to only set
RTX_FRAME_RELATED_P on appropriate insns. */
cfa.reg = dwf_regno (dest);
- cfa_temp.reg = cfa.reg;
- cfa_temp.offset = cfa.offset;
+ cur_trace->cfa_temp.reg = cfa.reg;
+ cur_trace->cfa_temp.offset = cfa.offset;
}
else
{
@@ -1806,8 +1881,9 @@ dwarf2out_frame_debug_expr (rtx expr)
offset = INTVAL (XEXP (src, 1));
break;
case REG:
- gcc_assert (dwf_regno (XEXP (src, 1)) == cfa_temp.reg);
- offset = cfa_temp.offset;
+ gcc_assert (dwf_regno (XEXP (src, 1))
+ == cur_trace->cfa_temp.reg);
+ offset = cur_trace->cfa_temp.offset;
break;
default:
gcc_unreachable ();
@@ -1829,8 +1905,8 @@ dwarf2out_frame_debug_expr (rtx expr)
offset = -offset;
if (cfa.reg == dw_stack_pointer_regnum)
cfa.offset += offset;
- if (cfa_store.reg == dw_stack_pointer_regnum)
- cfa_store.offset += offset;
+ if (cur_trace->cfa_store.reg == dw_stack_pointer_regnum)
+ cur_trace->cfa_store.offset += offset;
}
else if (dest == hard_frame_pointer_rtx)
{
@@ -1863,28 +1939,29 @@ dwarf2out_frame_debug_expr (rtx expr)
cfa.offset += offset;
cfa.reg = dwf_regno (dest);
/* Or used to save regs to the stack. */
- cfa_temp.reg = cfa.reg;
- cfa_temp.offset = cfa.offset;
+ cur_trace->cfa_temp.reg = cfa.reg;
+ cur_trace->cfa_temp.offset = cfa.offset;
}
/* Rule 5 */
else if (REG_P (XEXP (src, 0))
- && dwf_regno (XEXP (src, 0)) == cfa_temp.reg
+ && dwf_regno (XEXP (src, 0)) == cur_trace->cfa_temp.reg
&& XEXP (src, 1) == stack_pointer_rtx)
{
/* Setting a scratch register that we will use instead
of SP for saving registers to the stack. */
gcc_assert (cfa.reg == dw_stack_pointer_regnum);
- cfa_store.reg = dwf_regno (dest);
- cfa_store.offset = cfa.offset - cfa_temp.offset;
+ cur_trace->cfa_store.reg = dwf_regno (dest);
+ cur_trace->cfa_store.offset
+ = cfa.offset - cur_trace->cfa_temp.offset;
}
/* Rule 9 */
else if (GET_CODE (src) == LO_SUM
&& CONST_INT_P (XEXP (src, 1)))
{
- cfa_temp.reg = dwf_regno (dest);
- cfa_temp.offset = INTVAL (XEXP (src, 1));
+ cur_trace->cfa_temp.reg = dwf_regno (dest);
+ cur_trace->cfa_temp.offset = INTVAL (XEXP (src, 1));
}
else
gcc_unreachable ();
@@ -1893,18 +1970,18 @@ dwarf2out_frame_debug_expr (rtx expr)
/* Rule 6 */
case CONST_INT:
- cfa_temp.reg = dwf_regno (dest);
- cfa_temp.offset = INTVAL (src);
+ cur_trace->cfa_temp.reg = dwf_regno (dest);
+ cur_trace->cfa_temp.offset = INTVAL (src);
break;
/* Rule 7 */
case IOR:
gcc_assert (REG_P (XEXP (src, 0))
- && dwf_regno (XEXP (src, 0)) == cfa_temp.reg
+ && dwf_regno (XEXP (src, 0)) == cur_trace->cfa_temp.reg
&& CONST_INT_P (XEXP (src, 1)));
- cfa_temp.reg = dwf_regno (dest);
- cfa_temp.offset |= INTVAL (XEXP (src, 1));
+ cur_trace->cfa_temp.reg = dwf_regno (dest);
+ cur_trace->cfa_temp.offset |= INTVAL (XEXP (src, 1));
break;
/* Skip over HIGH, assuming it will be followed by a LO_SUM,
@@ -1931,10 +2008,11 @@ dwarf2out_frame_debug_expr (rtx expr)
Thus we must flush whatever we have queued first. */
dwarf2out_flush_queued_reg_saves ();
- gcc_assert (cfa_store.reg == dwf_regno (XEXP (src, 0)));
+ gcc_assert (cur_trace->cfa_store.reg
+ == dwf_regno (XEXP (src, 0)));
fde->stack_realign = 1;
fde->stack_realignment = INTVAL (XEXP (src, 1));
- cfa_store.offset = 0;
+ cur_trace->cfa_store.offset = 0;
if (cfa.reg != dw_stack_pointer_regnum
&& cfa.reg != dw_frame_pointer_regnum)
@@ -1965,16 +2043,16 @@ dwarf2out_frame_debug_expr (rtx expr)
offset = -INTVAL (XEXP (XEXP (XEXP (dest, 0), 1), 1));
gcc_assert (REGNO (XEXP (XEXP (dest, 0), 0)) == STACK_POINTER_REGNUM
- && cfa_store.reg == dw_stack_pointer_regnum);
+ && cur_trace->cfa_store.reg == dw_stack_pointer_regnum);
- cfa_store.offset += offset;
+ cur_trace->cfa_store.offset += offset;
if (cfa.reg == dw_stack_pointer_regnum)
- cfa.offset = cfa_store.offset;
+ cfa.offset = cur_trace->cfa_store.offset;
if (GET_CODE (XEXP (dest, 0)) == POST_MODIFY)
- offset -= cfa_store.offset;
+ offset -= cur_trace->cfa_store.offset;
else
- offset = -cfa_store.offset;
+ offset = -cur_trace->cfa_store.offset;
break;
/* Rule 11 */
@@ -1987,9 +2065,9 @@ dwarf2out_frame_debug_expr (rtx expr)
gcc_assert ((REGNO (XEXP (XEXP (dest, 0), 0))
== STACK_POINTER_REGNUM)
- && cfa_store.reg == dw_stack_pointer_regnum);
+ && cur_trace->cfa_store.reg == dw_stack_pointer_regnum);
- cfa_store.offset += offset;
+ cur_trace->cfa_store.offset += offset;
/* Rule 18: If stack is aligned, we will use FP as a
reference to represent the address of the stored
@@ -1999,16 +2077,16 @@ dwarf2out_frame_debug_expr (rtx expr)
&& src == hard_frame_pointer_rtx)
{
gcc_assert (cfa.reg != dw_frame_pointer_regnum);
- cfa_store.offset = 0;
+ cur_trace->cfa_store.offset = 0;
}
if (cfa.reg == dw_stack_pointer_regnum)
- cfa.offset = cfa_store.offset;
+ cfa.offset = cur_trace->cfa_store.offset;
if (GET_CODE (XEXP (dest, 0)) == POST_DEC)
- offset += -cfa_store.offset;
+ offset += -cur_trace->cfa_store.offset;
else
- offset = -cfa_store.offset;
+ offset = -cur_trace->cfa_store.offset;
break;
/* Rule 12 */
@@ -2029,12 +2107,12 @@ dwarf2out_frame_debug_expr (rtx expr)
if (cfa.reg == regno)
offset -= cfa.offset;
- else if (cfa_store.reg == regno)
- offset -= cfa_store.offset;
+ else if (cur_trace->cfa_store.reg == regno)
+ offset -= cur_trace->cfa_store.offset;
else
{
- gcc_assert (cfa_temp.reg == regno);
- offset -= cfa_temp.offset;
+ gcc_assert (cur_trace->cfa_temp.reg == regno);
+ offset -= cur_trace->cfa_temp.offset;
}
}
break;
@@ -2047,21 +2125,22 @@ dwarf2out_frame_debug_expr (rtx expr)
if (cfa.reg == regno)
offset = -cfa.offset;
- else if (cfa_store.reg == regno)
- offset = -cfa_store.offset;
+ else if (cur_trace->cfa_store.reg == regno)
+ offset = -cur_trace->cfa_store.offset;
else
{
- gcc_assert (cfa_temp.reg == regno);
- offset = -cfa_temp.offset;
+ gcc_assert (cur_trace->cfa_temp.reg == regno);
+ offset = -cur_trace->cfa_temp.offset;
}
}
break;
/* Rule 14 */
case POST_INC:
- gcc_assert (cfa_temp.reg == dwf_regno (XEXP (XEXP (dest, 0), 0)));
- offset = -cfa_temp.offset;
- cfa_temp.offset -= GET_MODE_SIZE (GET_MODE (dest));
+ gcc_assert (cur_trace->cfa_temp.reg
+ == dwf_regno (XEXP (XEXP (dest, 0), 0)));
+ offset = -cur_trace->cfa_temp.offset;
+ cur_trace->cfa_temp.offset -= GET_MODE_SIZE (GET_MODE (dest));
break;
default:
@@ -2453,7 +2532,7 @@ add_cfis_to_fde (void)
}
/* Scan the function and create the initial set of CFI notes. */
-
+
static void
create_cfi_notes (void)
{
@@ -2692,6 +2771,60 @@ initial_return_save (rtx rtl)
}
}
+static void
+create_cie_data (void)
+{
+ dw_cfa_location loc;
+ dw_trace_info cie_trace;
+
+ dw_stack_pointer_regnum = DWARF_FRAME_REGNUM (STACK_POINTER_REGNUM);
+ dw_frame_pointer_regnum = DWARF_FRAME_REGNUM (HARD_FRAME_POINTER_REGNUM);
+
+ memset (&cie_trace, 0, sizeof(cie_trace));
+ cur_trace = &cie_trace;
+
+ add_cfi_vec = &cie_cfi_vec;
+ cie_cfi_row = cur_row = new_cfi_row ();
+
+ /* On entry, the Canonical Frame Address is at SP. */
+ memset(&loc, 0, sizeof (loc));
+ loc.reg = dw_stack_pointer_regnum;
+ loc.offset = INCOMING_FRAME_SP_OFFSET;
+ def_cfa_1 (&loc);
+
+ if (targetm.debug_unwind_info () == UI_DWARF2
+ || targetm_common.except_unwind_info (&global_options) == UI_DWARF2)
+ {
+ initial_return_save (INCOMING_RETURN_ADDR_RTX);
+
+ /* For a few targets, we have the return address incoming into a
+ register, but choose a different return column. This will result
+ in a DW_CFA_register for the return, and an entry in
+ regs_saved_in_regs to match. If the target later stores that
+ return address register to the stack, we want to be able to emit
+ the DW_CFA_offset against the return column, not the intermediate
+ save register. Save the contents of regs_saved_in_regs so that
+ we can re-initialize it at the start of each function. */
+ switch (VEC_length (reg_saved_in_data, cie_trace.regs_saved_in_regs))
+ {
+ case 0:
+ break;
+ case 1:
+ cie_return_save = ggc_alloc_reg_saved_in_data ();
+ *cie_return_save = *VEC_index (reg_saved_in_data,
+ cie_trace.regs_saved_in_regs, 0);
+ VEC_free (reg_saved_in_data, heap, cie_trace.regs_saved_in_regs);
+ break;
+ default:
+ gcc_unreachable ();
+ }
+ }
+
+ add_cfi_vec = NULL;
+ cur_row = NULL;
+ cur_trace = NULL;
+}
+
/* Annotate the function with NOTE_INSN_CFI notes to record the CFI
state at each location within the function. These notes will be
emitted during pass_final. */
@@ -2699,68 +2832,26 @@ initial_return_save (rtx rtl)
static unsigned int
execute_dwarf2_frame (void)
{
+ dw_trace_info dummy_trace;
+
gcc_checking_assert (queued_reg_saves == NULL);
- gcc_checking_assert (regs_saved_in_regs == NULL);
/* The first time we're called, compute the incoming frame state. */
if (cie_cfi_vec == NULL)
- {
- dw_cfa_location loc;
-
- dw_stack_pointer_regnum = DWARF_FRAME_REGNUM (STACK_POINTER_REGNUM);
- dw_frame_pointer_regnum = DWARF_FRAME_REGNUM (HARD_FRAME_POINTER_REGNUM);
-
- add_cfi_vec = &cie_cfi_vec;
- cie_cfi_row = cur_row = new_cfi_row ();
-
- /* On entry, the Canonical Frame Address is at SP. */
- memset(&loc, 0, sizeof (loc));
- loc.reg = dw_stack_pointer_regnum;
- loc.offset = INCOMING_FRAME_SP_OFFSET;
- def_cfa_1 (&loc);
-
- if (targetm.debug_unwind_info () == UI_DWARF2
- || targetm_common.except_unwind_info (&global_options) == UI_DWARF2)
- {
- initial_return_save (INCOMING_RETURN_ADDR_RTX);
-
- /* For a few targets, we have the return address incoming into a
- register, but choose a different return column. This will result
- in a DW_CFA_register for the return, and an entry in
- regs_saved_in_regs to match. If the target later stores that
- return address register to the stack, we want to be able to emit
- the DW_CFA_offset against the return column, not the intermediate
- save register. Save the contents of regs_saved_in_regs so that
- we can re-initialize it at the start of each function. */
- switch (VEC_length (reg_saved_in_data, regs_saved_in_regs))
- {
- case 0:
- break;
- case 1:
- cie_return_save = ggc_alloc_reg_saved_in_data ();
- *cie_return_save = *VEC_index (reg_saved_in_data,
- regs_saved_in_regs, 0);
- VEC_pop (reg_saved_in_data, regs_saved_in_regs);
- break;
- default:
- gcc_unreachable ();
- }
- }
+ create_cie_data ();
- add_cfi_vec = NULL;
- }
+ memset (&dummy_trace, 0, sizeof(dummy_trace));
+ cur_trace = &dummy_trace;
/* Set up state for generating call frame debug info. */
cur_row = copy_cfi_row (cie_cfi_row);
if (cie_return_save)
VEC_safe_push (reg_saved_in_data, heap,
- regs_saved_in_regs, cie_return_save);
-
- cfa_store = cur_row->cfa;
- args_size = 0;
+ cur_trace->regs_saved_in_regs, cie_return_save);
- memset (&cfa_temp, 0, sizeof(cfa_temp));
- cfa_temp.reg = INVALID_REGNUM;
+ cur_trace->cfa_store = cur_row->cfa;
+ cur_trace->cfa_temp.reg = INVALID_REGNUM;
+ queued_args_size = 0;
dwarf2out_alloc_current_fde ();
@@ -2771,11 +2862,12 @@ execute_dwarf2_frame (void)
/* Reset all function-specific information, particularly for GC. */
XDELETEVEC (barrier_args_size);
barrier_args_size = NULL;
- VEC_free (reg_saved_in_data, heap, regs_saved_in_regs);
+ VEC_free (reg_saved_in_data, heap, cur_trace->regs_saved_in_regs);
VEC_free (queued_reg_save, heap, queued_reg_saves);
free_cfi_row (cur_row);
cur_row = NULL;
+ cur_trace = NULL;
return 0;
}
@@ -2864,7 +2956,7 @@ output_cfa_loc (dw_cfi_ref cfi, int for_eh)
if (cfi->dw_cfi_opc == DW_CFA_expression)
{
- unsigned r =
+ unsigned r =
DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, for_eh);
dw2_asm_output_data (1, r, NULL);
loc = cfi->dw_cfi_oprnd2.dw_cfi_loc;
@@ -2890,7 +2982,7 @@ output_cfa_loc_raw (dw_cfi_ref cfi)
if (cfi->dw_cfi_opc == DW_CFA_expression)
{
- unsigned r =
+ unsigned r =
DWARF2_FRAME_REG_OUT (cfi->dw_cfi_oprnd1.dw_cfi_reg_num, 1);
fprintf (asm_out_file, "%#x,", r);
loc = cfi->dw_cfi_oprnd2.dw_cfi_loc;
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* [PATCH 4/9] dwarf2cfi: Implement change_cfi_row.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (3 preceding siblings ...)
2011-07-14 23:10 ` [PATCH 8/9] dwarf2cfi: Introduce dw_trace_info Richard Henderson
@ 2011-07-14 23:10 ` Richard Henderson
2011-07-14 23:10 ` [PATCH 2/9] dwarf2cfi: Rename cfi_insn to add_cfi_insn Richard Henderson
` (5 subsequent siblings)
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:10 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
Add a generic function to adjust cfi state from one row to another.
Use this to implement text section switching. This will also be
usable for arbitrary changes around a cfg for shrink-wrapping.
---
gcc/dwarf2cfi.c | 376 +++++++++++++++++++++++++------------------------------
gcc/dwarf2out.c | 159 ++++++++++++++++++------
gcc/dwarf2out.h | 3 +-
3 files changed, 290 insertions(+), 248 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index 36fa7f8..745e137 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -285,6 +285,28 @@ add_cfi (dw_cfi_ref cfi)
VEC_safe_push (dw_cfi_ref, gc, *add_cfi_vec, cfi);
}
+static void
+add_cfi_args_size (HOST_WIDE_INT size)
+{
+ dw_cfi_ref cfi = new_cfi ();
+
+ cfi->dw_cfi_opc = DW_CFA_GNU_args_size;
+ cfi->dw_cfi_oprnd1.dw_cfi_offset = size;
+
+ add_cfi (cfi);
+}
+
+static void
+add_cfi_restore (unsigned reg)
+{
+ dw_cfi_ref cfi = new_cfi ();
+
+ cfi->dw_cfi_opc = (reg & ~0x3f ? DW_CFA_restore_extended : DW_CFA_restore);
+ cfi->dw_cfi_oprnd1.dw_cfi_reg_num = reg;
+
+ add_cfi (cfi);
+}
+
/* Perform ROW->REG_SAVE[COLUMN] = CFI. CFI may be null, indicating
that the register column is no longer saved. */
@@ -474,64 +496,109 @@ cfa_equal_p (const dw_cfa_location *loc1, const dw_cfa_location *loc2)
|| loc1->base_offset == loc2->base_offset));
}
-/* This routine does the actual work. The CFA is now calculated from
- the dw_cfa_location structure. */
+/* Determine if two CFI operands are identical. */
-static void
-def_cfa_1 (dw_cfa_location *loc_p)
+static bool
+cfi_oprnd_equal_p (enum dw_cfi_oprnd_type t, dw_cfi_oprnd *a, dw_cfi_oprnd *b)
{
- dw_cfi_ref cfi;
- dw_cfa_location loc = *loc_p;
+ switch (t)
+ {
+ case dw_cfi_oprnd_unused:
+ return true;
+ case dw_cfi_oprnd_reg_num:
+ return a->dw_cfi_reg_num == b->dw_cfi_reg_num;
+ case dw_cfi_oprnd_offset:
+ return a->dw_cfi_offset == b->dw_cfi_offset;
+ case dw_cfi_oprnd_addr:
+ return (a->dw_cfi_addr == b->dw_cfi_addr
+ || strcmp (a->dw_cfi_addr, b->dw_cfi_addr) == 0);
+ case dw_cfi_oprnd_loc:
+ return loc_descr_equal_p (a->dw_cfi_loc, b->dw_cfi_loc);
+ }
+ gcc_unreachable ();
+}
- if (cfa_store.reg == loc.reg && loc.indirect == 0)
- cfa_store.offset = loc.offset;
+/* Determine if two CFI entries are identical. */
+
+static bool
+cfi_equal_p (dw_cfi_ref a, dw_cfi_ref b)
+{
+ enum dwarf_call_frame_info opc;
+
+ /* Make things easier for our callers, including missing operands. */
+ if (a == b)
+ return true;
+ if (a == NULL || b == NULL)
+ return false;
+
+ /* Obviously, the opcodes must match. */
+ opc = a->dw_cfi_opc;
+ if (opc != b->dw_cfi_opc)
+ return false;
+
+ /* Compare the two operands, re-using the type of the operands as
+ already exposed elsewhere. */
+ return (cfi_oprnd_equal_p (dw_cfi_oprnd1_desc (opc),
+ &a->dw_cfi_oprnd1, &b->dw_cfi_oprnd1)
+ && cfi_oprnd_equal_p (dw_cfi_oprnd2_desc (opc),
+ &a->dw_cfi_oprnd2, &b->dw_cfi_oprnd2));
+}
+
+/* The CFA is now calculated from NEW_CFA. Consider OLD_CFA in determining
+ what opcode to emit. Returns the CFI opcode to effect the change, or
+ NULL if NEW_CFA == OLD_CFA. */
+
+static dw_cfi_ref
+def_cfa_0 (dw_cfa_location *old_cfa, dw_cfa_location *new_cfa)
+{
+ dw_cfi_ref cfi;
/* If nothing changed, no need to issue any call frame instructions. */
- if (cfa_equal_p (&loc, &cur_row->cfa))
- return;
+ if (cfa_equal_p (old_cfa, new_cfa))
+ return NULL;
cfi = new_cfi ();
- if (loc.reg == cur_row->cfa.reg && !loc.indirect && !cur_row->cfa.indirect)
+ if (new_cfa->reg == old_cfa->reg && !new_cfa->indirect && !old_cfa->indirect)
{
/* Construct a "DW_CFA_def_cfa_offset <offset>" instruction, indicating
the CFA register did not change but the offset did. The data
factoring for DW_CFA_def_cfa_offset_sf happens in output_cfi, or
in the assembler via the .cfi_def_cfa_offset directive. */
- if (loc.offset < 0)
+ if (new_cfa->offset < 0)
cfi->dw_cfi_opc = DW_CFA_def_cfa_offset_sf;
else
cfi->dw_cfi_opc = DW_CFA_def_cfa_offset;
- cfi->dw_cfi_oprnd1.dw_cfi_offset = loc.offset;
+ cfi->dw_cfi_oprnd1.dw_cfi_offset = new_cfa->offset;
}
#ifndef MIPS_DEBUGGING_INFO /* SGI dbx thinks this means no offset. */
- else if (loc.offset == cur_row->cfa.offset
- && cur_row->cfa.reg != INVALID_REGNUM
- && !loc.indirect
- && !cur_row->cfa.indirect)
+ else if (new_cfa->offset == old_cfa->offset
+ && old_cfa->reg != INVALID_REGNUM
+ && !new_cfa->indirect
+ && !old_cfa->indirect)
{
/* Construct a "DW_CFA_def_cfa_register <register>" instruction,
indicating the CFA register has changed to <register> but the
offset has not changed. */
cfi->dw_cfi_opc = DW_CFA_def_cfa_register;
- cfi->dw_cfi_oprnd1.dw_cfi_reg_num = loc.reg;
+ cfi->dw_cfi_oprnd1.dw_cfi_reg_num = new_cfa->reg;
}
#endif
- else if (loc.indirect == 0)
+ else if (new_cfa->indirect == 0)
{
/* Construct a "DW_CFA_def_cfa <register> <offset>" instruction,
indicating the CFA register has changed to <register> with
the specified offset. The data factoring for DW_CFA_def_cfa_sf
happens in output_cfi, or in the assembler via the .cfi_def_cfa
directive. */
- if (loc.offset < 0)
+ if (new_cfa->offset < 0)
cfi->dw_cfi_opc = DW_CFA_def_cfa_sf;
else
cfi->dw_cfi_opc = DW_CFA_def_cfa;
- cfi->dw_cfi_oprnd1.dw_cfi_reg_num = loc.reg;
- cfi->dw_cfi_oprnd2.dw_cfi_offset = loc.offset;
+ cfi->dw_cfi_oprnd1.dw_cfi_reg_num = new_cfa->reg;
+ cfi->dw_cfi_oprnd2.dw_cfi_offset = new_cfa->offset;
}
else
{
@@ -541,14 +608,32 @@ def_cfa_1 (dw_cfa_location *loc_p)
struct dw_loc_descr_struct *loc_list;
cfi->dw_cfi_opc = DW_CFA_def_cfa_expression;
- loc_list = build_cfa_loc (&loc, 0);
+ loc_list = build_cfa_loc (new_cfa, 0);
cfi->dw_cfi_oprnd1.dw_cfi_loc = loc_list;
-
- cur_row->cfa_cfi = cfi;
}
- add_cfi (cfi);
- cur_row->cfa = loc;
+ return cfi;
+}
+
+/* Similarly, but take OLD_CFA from CUR_ROW, and update it after the fact. */
+
+static void
+def_cfa_1 (dw_cfa_location *new_cfa)
+{
+ dw_cfi_ref cfi;
+
+ if (cfa_store.reg == new_cfa->reg && new_cfa->indirect == 0)
+ cfa_store.offset = new_cfa->offset;
+
+ cfi = def_cfa_0 (&cur_row->cfa, new_cfa);
+ if (cfi)
+ {
+ cur_row->cfa = *new_cfa;
+ if (cfi->dw_cfi_opc == DW_CFA_def_cfa_expression)
+ cur_row->cfa_cfi = cfi;
+
+ add_cfi (cfi);
+ }
}
/* Add the CFI for saving a register. REG is the CFA column number.
@@ -871,17 +956,11 @@ compute_barrier_args_size (void)
static void
dwarf2out_args_size (HOST_WIDE_INT size)
{
- dw_cfi_ref cfi;
-
if (size == cur_row->args_size)
return;
cur_row->args_size = size;
-
- cfi = new_cfi ();
- cfi->dw_cfi_opc = DW_CFA_GNU_args_size;
- cfi->dw_cfi_oprnd1.dw_cfi_offset = size;
- add_cfi (cfi);
+ add_cfi_args_size (size);
}
/* Record a stack adjustment of OFFSET bytes. */
@@ -1385,13 +1464,9 @@ dwarf2out_frame_debug_cfa_expression (rtx set)
static void
dwarf2out_frame_debug_cfa_restore (rtx reg)
{
- dw_cfi_ref cfi = new_cfi ();
unsigned int regno = dwf_regno (reg);
- cfi->dw_cfi_opc = (regno & ~0x3f ? DW_CFA_restore_extended : DW_CFA_restore);
- cfi->dw_cfi_oprnd1.dw_cfi_reg_num = regno;
-
- add_cfi (cfi);
+ add_cfi_restore (regno);
update_row_reg_save (cur_row, regno, NULL);
}
@@ -2238,6 +2313,48 @@ dwarf2out_frame_debug (rtx insn, bool after_p)
dwarf2out_flush_queued_reg_saves ();
}
+/* Emit CFI info to change the state from OLD_ROW to NEW_ROW. */
+
+static void
+change_cfi_row (dw_cfi_row_ref old_row, dw_cfi_row_ref new_row)
+{
+ size_t i, n_old, n_new, n_max;
+ dw_cfi_ref cfi;
+
+ if (new_row->cfa_cfi && !cfi_equal_p (old_row->cfa_cfi, new_row->cfa_cfi))
+ add_cfi (new_row->cfa_cfi);
+ else
+ {
+ cfi = def_cfa_0 (&old_row->cfa, &new_row->cfa);
+ if (cfi)
+ add_cfi (cfi);
+ }
+
+ if (old_row->args_size != new_row->args_size)
+ add_cfi_args_size (new_row->args_size);
+
+ n_old = VEC_length (dw_cfi_ref, old_row->reg_save);
+ n_new = VEC_length (dw_cfi_ref, new_row->reg_save);
+ n_max = MAX (n_old, n_new);
+
+ for (i = 0; i < n_max; ++i)
+ {
+ dw_cfi_ref r_old = NULL, r_new = NULL;
+
+ if (i < n_old)
+ r_old = VEC_index (dw_cfi_ref, old_row->reg_save, i);
+ if (i < n_new)
+ r_new = VEC_index (dw_cfi_ref, new_row->reg_save, i);
+
+ if (r_old == r_new)
+ ;
+ else if (r_new == NULL)
+ add_cfi_restore (i);
+ else if (!cfi_equal_p (r_old, r_new))
+ add_cfi (r_new);
+ }
+}
+
/* Examine CFI and return true if a cfi label and set_loc is needed
beforehand. Even when generating CFI assembler instructions, we
still have to add the cfi to the list so that lookup_cfa_1 works
@@ -2291,6 +2408,8 @@ add_cfis_to_fde (void)
if (NOTE_P (insn) && NOTE_KIND (insn) == NOTE_INSN_SWITCH_TEXT_SECTIONS)
{
+ fde->dw_fde_switch_cfi_index
+ = VEC_length (dw_cfi_ref, fde->dw_fde_cfi);
/* Don't attempt to advance_loc4 between labels
in different sections. */
first = true;
@@ -2370,6 +2489,16 @@ create_cfi_notes (void)
add_cfi_insn = insn;
dwarf2out_frame_debug_restore_state ();
break;
+
+ case NOTE_INSN_SWITCH_TEXT_SECTIONS:
+ /* In dwarf2out_switch_text_section, we'll begin a new FDE
+ for the portion of the function in the alternate text
+ section. The row state at the very beginning of that
+ new FDE will be exactly the row state from the CIE.
+ Emit whatever CFIs are necessary to make CUR_ROW current. */
+ add_cfi_insn = insn;
+ change_cfi_row (cie_cfi_row, cur_row);
+ break;
}
continue;
}
@@ -3047,175 +3176,6 @@ dwarf2out_emit_cfi (dw_cfi_ref cfi)
if (dwarf2out_do_cfi_asm ())
output_cfi_directive (asm_out_file, cfi);
}
-
-/* Output CFIs from VEC, up to index UPTO, to bring current FDE to the
- same state as after executing CFIs in CFI chain. DO_CFI_ASM is
- true if .cfi_* directives shall be emitted, false otherwise. If it
- is false, FDE and FOR_EH are the other arguments to pass to
- output_cfi. */
-
-void
-output_cfis (cfi_vec vec, int upto, bool do_cfi_asm,
- dw_fde_ref fde, bool for_eh)
-{
- int ix;
- struct dw_cfi_struct cfi_buf;
- dw_cfi_ref cfi2;
- dw_cfi_ref cfi_args_size = NULL, cfi_cfa = NULL, cfi_cfa_offset = NULL;
- VEC(dw_cfi_ref, heap) *regs = VEC_alloc (dw_cfi_ref, heap, 32);
- unsigned int len, idx;
-
- for (ix = 0; ix < upto + 1; ix++)
- {
- dw_cfi_ref cfi = ix < upto ? VEC_index (dw_cfi_ref, vec, ix) : NULL;
- switch (cfi ? cfi->dw_cfi_opc : DW_CFA_nop)
- {
- case DW_CFA_advance_loc:
- case DW_CFA_advance_loc1:
- case DW_CFA_advance_loc2:
- case DW_CFA_advance_loc4:
- case DW_CFA_MIPS_advance_loc8:
- case DW_CFA_set_loc:
- /* All advances should be ignored. */
- break;
- case DW_CFA_remember_state:
- {
- dw_cfi_ref args_size = cfi_args_size;
-
- /* Skip everything between .cfi_remember_state and
- .cfi_restore_state. */
- ix++;
- if (ix == upto)
- goto flush_all;
-
- for (; ix < upto; ix++)
- {
- cfi2 = VEC_index (dw_cfi_ref, vec, ix);
- if (cfi2->dw_cfi_opc == DW_CFA_restore_state)
- break;
- else if (cfi2->dw_cfi_opc == DW_CFA_GNU_args_size)
- args_size = cfi2;
- else
- gcc_assert (cfi2->dw_cfi_opc != DW_CFA_remember_state);
- }
-
- cfi_args_size = args_size;
- break;
- }
- case DW_CFA_GNU_args_size:
- cfi_args_size = cfi;
- break;
- case DW_CFA_GNU_window_save:
- goto flush_all;
- case DW_CFA_offset:
- case DW_CFA_offset_extended:
- case DW_CFA_offset_extended_sf:
- case DW_CFA_restore:
- case DW_CFA_restore_extended:
- case DW_CFA_undefined:
- case DW_CFA_same_value:
- case DW_CFA_register:
- case DW_CFA_val_offset:
- case DW_CFA_val_offset_sf:
- case DW_CFA_expression:
- case DW_CFA_val_expression:
- case DW_CFA_GNU_negative_offset_extended:
- if (VEC_length (dw_cfi_ref, regs)
- <= cfi->dw_cfi_oprnd1.dw_cfi_reg_num)
- VEC_safe_grow_cleared (dw_cfi_ref, heap, regs,
- cfi->dw_cfi_oprnd1.dw_cfi_reg_num + 1);
- VEC_replace (dw_cfi_ref, regs, cfi->dw_cfi_oprnd1.dw_cfi_reg_num,
- cfi);
- break;
- case DW_CFA_def_cfa:
- case DW_CFA_def_cfa_sf:
- case DW_CFA_def_cfa_expression:
- cfi_cfa = cfi;
- cfi_cfa_offset = cfi;
- break;
- case DW_CFA_def_cfa_register:
- cfi_cfa = cfi;
- break;
- case DW_CFA_def_cfa_offset:
- case DW_CFA_def_cfa_offset_sf:
- cfi_cfa_offset = cfi;
- break;
- case DW_CFA_nop:
- gcc_assert (cfi == NULL);
- flush_all:
- len = VEC_length (dw_cfi_ref, regs);
- for (idx = 0; idx < len; idx++)
- {
- cfi2 = VEC_replace (dw_cfi_ref, regs, idx, NULL);
- if (cfi2 != NULL
- && cfi2->dw_cfi_opc != DW_CFA_restore
- && cfi2->dw_cfi_opc != DW_CFA_restore_extended)
- {
- if (do_cfi_asm)
- output_cfi_directive (asm_out_file, cfi2);
- else
- output_cfi (cfi2, fde, for_eh);
- }
- }
- if (cfi_cfa && cfi_cfa_offset && cfi_cfa_offset != cfi_cfa)
- {
- gcc_assert (cfi_cfa->dw_cfi_opc != DW_CFA_def_cfa_expression);
- cfi_buf = *cfi_cfa;
- switch (cfi_cfa_offset->dw_cfi_opc)
- {
- case DW_CFA_def_cfa_offset:
- cfi_buf.dw_cfi_opc = DW_CFA_def_cfa;
- cfi_buf.dw_cfi_oprnd2 = cfi_cfa_offset->dw_cfi_oprnd1;
- break;
- case DW_CFA_def_cfa_offset_sf:
- cfi_buf.dw_cfi_opc = DW_CFA_def_cfa_sf;
- cfi_buf.dw_cfi_oprnd2 = cfi_cfa_offset->dw_cfi_oprnd1;
- break;
- case DW_CFA_def_cfa:
- case DW_CFA_def_cfa_sf:
- cfi_buf.dw_cfi_opc = cfi_cfa_offset->dw_cfi_opc;
- cfi_buf.dw_cfi_oprnd2 = cfi_cfa_offset->dw_cfi_oprnd2;
- break;
- default:
- gcc_unreachable ();
- }
- cfi_cfa = &cfi_buf;
- }
- else if (cfi_cfa_offset)
- cfi_cfa = cfi_cfa_offset;
- if (cfi_cfa)
- {
- if (do_cfi_asm)
- output_cfi_directive (asm_out_file, cfi_cfa);
- else
- output_cfi (cfi_cfa, fde, for_eh);
- }
- cfi_cfa = NULL;
- cfi_cfa_offset = NULL;
- if (cfi_args_size
- && cfi_args_size->dw_cfi_oprnd1.dw_cfi_offset)
- {
- if (do_cfi_asm)
- output_cfi_directive (asm_out_file, cfi_args_size);
- else
- output_cfi (cfi_args_size, fde, for_eh);
- }
- cfi_args_size = NULL;
- if (cfi == NULL)
- {
- VEC_free (dw_cfi_ref, heap, regs);
- return;
- }
- else if (do_cfi_asm)
- output_cfi_directive (asm_out_file, cfi);
- else
- output_cfi (cfi, fde, for_eh);
- break;
- default:
- gcc_unreachable ();
- }
- }
-}
\f
/* Save the result of dwarf2out_do_frame across PCH.
diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index 8fdebc6..3041bb8 100644
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -518,11 +518,9 @@ output_fde (dw_fde_ref fde, bool for_eh, bool second,
char *section_start_label, int fde_encoding, char *augmentation,
bool any_lsda_needed, int lsda_encoding)
{
- int ix;
const char *begin, *end;
static unsigned int j;
char l1[20], l2[20];
- dw_cfi_ref cfi;
targetm.asm_out.emit_unwind_label (asm_out_file, fde->decl, for_eh,
/* empty */ 0);
@@ -602,36 +600,24 @@ output_fde (dw_fde_ref fde, bool for_eh, bool second,
dw2_asm_output_data_uleb128 (0, "Augmentation size");
}
- /* Loop through the Call Frame Instructions associated with
- this FDE. */
+ /* Loop through the Call Frame Instructions associated with this FDE. */
fde->dw_fde_current_label = begin;
- if (fde->dw_fde_second_begin == NULL)
- FOR_EACH_VEC_ELT (dw_cfi_ref, fde->dw_fde_cfi, ix, cfi)
- output_cfi (cfi, fde, for_eh);
- else if (!second)
- {
- if (fde->dw_fde_switch_cfi_index > 0)
- FOR_EACH_VEC_ELT (dw_cfi_ref, fde->dw_fde_cfi, ix, cfi)
- {
- if (ix == fde->dw_fde_switch_cfi_index)
- break;
- output_cfi (cfi, fde, for_eh);
- }
- }
- else
- {
- int i, from = 0;
- int until = VEC_length (dw_cfi_ref, fde->dw_fde_cfi);
+ {
+ size_t from, until, i;
- if (fde->dw_fde_switch_cfi_index > 0)
- {
- from = fde->dw_fde_switch_cfi_index;
- output_cfis (fde->dw_fde_cfi, from, false, fde, for_eh);
- }
- for (i = from; i < until; i++)
- output_cfi (VEC_index (dw_cfi_ref, fde->dw_fde_cfi, i),
- fde, for_eh);
- }
+ from = 0;
+ until = VEC_length (dw_cfi_ref, fde->dw_fde_cfi);
+
+ if (fde->dw_fde_second_begin == NULL)
+ ;
+ else if (!second)
+ until = fde->dw_fde_switch_cfi_index;
+ else
+ from = fde->dw_fde_switch_cfi_index;
+
+ for (i = from; i < until; i++)
+ output_cfi (VEC_index (dw_cfi_ref, fde->dw_fde_cfi, i), fde, for_eh);
+ }
/* If we are to emit a ref/link from function bodies to their frame tables,
do it now. This is typically performed to make sure that tables
@@ -1183,16 +1169,8 @@ dwarf2out_switch_text_section (void)
= (sect == text_section
|| (cold_text_section && sect == cold_text_section));
- fde->dw_fde_switch_cfi_index = VEC_length (dw_cfi_ref, fde->dw_fde_cfi);
-
if (dwarf2out_do_cfi_asm ())
- {
- dwarf2out_do_cfi_startproc (true);
- /* As this is a different FDE, insert all current CFI instructions
- again. */
- output_cfis (fde->dw_fde_cfi, fde->dw_fde_switch_cfi_index,
- true, fde, true);
- }
+ dwarf2out_do_cfi_startproc (true);
var_location_switch_text_section ();
@@ -1638,6 +1616,109 @@ add_loc_descr (dw_loc_descr_ref *list_head, dw_loc_descr_ref descr)
*d = descr;
}
+/* Compare two location operands for exact equality. */
+
+static bool
+dw_val_equal_p (dw_val_node *a, dw_val_node *b)
+{
+ if (a->val_class != b->val_class)
+ return false;
+ switch (a->val_class)
+ {
+ case dw_val_class_none:
+ return true;
+ case dw_val_class_addr:
+ return rtx_equal_p (a->v.val_addr, b->v.val_addr);
+
+ case dw_val_class_offset:
+ case dw_val_class_unsigned_const:
+ case dw_val_class_const:
+ case dw_val_class_range_list:
+ case dw_val_class_lineptr:
+ case dw_val_class_macptr:
+ /* These are all HOST_WIDE_INT, signed or unsigned. */
+ return a->v.val_unsigned == b->v.val_unsigned;
+
+ case dw_val_class_loc:
+ return a->v.val_loc == b->v.val_loc;
+ case dw_val_class_loc_list:
+ return a->v.val_loc_list == b->v.val_loc_list;
+ case dw_val_class_die_ref:
+ return a->v.val_die_ref.die == b->v.val_die_ref.die;
+ case dw_val_class_fde_ref:
+ return a->v.val_fde_index == b->v.val_fde_index;
+ case dw_val_class_lbl_id:
+ return strcmp (a->v.val_lbl_id, b->v.val_lbl_id) == 0;
+ case dw_val_class_str:
+ return a->v.val_str == b->v.val_str;
+ case dw_val_class_flag:
+ return a->v.val_flag == b->v.val_flag;
+ case dw_val_class_file:
+ return a->v.val_file == b->v.val_file;
+ case dw_val_class_decl_ref:
+ return a->v.val_decl_ref == b->v.val_decl_ref;
+
+ case dw_val_class_const_double:
+ return (a->v.val_double.high == b->v.val_double.high
+ && a->v.val_double.low == b->v.val_double.low);
+
+ case dw_val_class_vec:
+ {
+ size_t a_len = a->v.val_vec.elt_size * a->v.val_vec.length;
+ size_t b_len = b->v.val_vec.elt_size * b->v.val_vec.length;
+
+ return (a_len == b_len
+ && !memcmp (a->v.val_vec.array, b->v.val_vec.array, a_len));
+ }
+
+ case dw_val_class_data8:
+ return memcmp (a->v.val_data8, b->v.val_data8, 8) == 0;
+
+ case dw_val_class_vms_delta:
+ return (!strcmp (a->v.val_vms_delta.lbl1, b->v.val_vms_delta.lbl1)
+ && !strcmp (a->v.val_vms_delta.lbl1, b->v.val_vms_delta.lbl1));
+ }
+ gcc_unreachable ();
+}
+
+/* Compare two location atoms for exact equality. */
+
+static bool
+loc_descr_equal_p_1 (dw_loc_descr_ref a, dw_loc_descr_ref b)
+{
+ if (a->dw_loc_opc != b->dw_loc_opc)
+ return false;
+
+ /* ??? This is only ever set for DW_OP_constNu, for N equal to the
+ address size, but since we always allocate cleared storage it
+ should be zero for other types of locations. */
+ if (a->dtprel != b->dtprel)
+ return false;
+
+ return (dw_val_equal_p (&a->dw_loc_oprnd1, &b->dw_loc_oprnd1)
+ && dw_val_equal_p (&a->dw_loc_oprnd2, &b->dw_loc_oprnd2));
+}
+
+/* Compare two complete location expressions for exact equality. */
+
+bool
+loc_descr_equal_p (dw_loc_descr_ref a, dw_loc_descr_ref b)
+{
+ while (1)
+ {
+ if (a == b)
+ return true;
+ if (a == NULL || b == NULL)
+ return false;
+ if (!loc_descr_equal_p_1 (a, b))
+ return false;
+
+ a = a->dw_loc_next;
+ b = b->dw_loc_next;
+ }
+}
+
+
/* Add a constant OFFSET to a location expression. */
static void
diff --git a/gcc/dwarf2out.h b/gcc/dwarf2out.h
index d0e76a7..711e8ab 100644
--- a/gcc/dwarf2out.h
+++ b/gcc/dwarf2out.h
@@ -134,6 +134,7 @@ typedef struct GTY(()) cfa_loc {
enum dw_val_class
{
+ dw_val_class_none,
dw_val_class_addr,
dw_val_class_offset,
dw_val_class_loc,
@@ -226,6 +227,7 @@ extern struct dw_loc_descr_struct *build_cfa_aligned_loc
extern struct dw_loc_descr_struct *mem_loc_descriptor
(rtx, enum machine_mode mode, enum machine_mode mem_mode,
enum var_init_status);
+extern bool loc_descr_equal_p (dw_loc_descr_ref, dw_loc_descr_ref);
extern enum machine_mode get_address_mode (rtx mem);
extern dw_fde_ref dwarf2out_alloc_current_fde (void);
@@ -239,7 +241,6 @@ extern void lookup_cfa_1 (dw_cfi_ref cfi, dw_cfa_location *loc,
extern bool cfa_equal_p (const dw_cfa_location *, const dw_cfa_location *);
extern void output_cfi (dw_cfi_ref, dw_fde_ref, int);
-extern void output_cfis (cfi_vec, int, bool, dw_fde_ref, bool);
extern GTY(()) cfi_vec cie_cfi_vec;
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* [PATCH 2/9] dwarf2cfi: Rename cfi_insn to add_cfi_insn.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (4 preceding siblings ...)
2011-07-14 23:10 ` [PATCH 4/9] dwarf2cfi: Implement change_cfi_row Richard Henderson
@ 2011-07-14 23:10 ` Richard Henderson
2011-07-14 23:16 ` [PATCH 9/9] dwarf2cfi: Generate and connect traces Richard Henderson
` (4 subsequent siblings)
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:10 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
Make it consistent with add_cfi_vec.
---
gcc/dwarf2cfi.c | 20 +++++++++++---------
1 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index 1c1b74f..eb59f28 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -86,7 +86,7 @@ static GTY(()) dw_cfi_row_ref cie_cfi_row;
static GTY(()) unsigned long dwarf2out_cfi_label_num;
/* The insn after which a new CFI note should be emitted. */
-static rtx cfi_insn;
+static rtx add_cfi_insn;
/* When non-null, add_cfi will add the CFI to this vector. */
static cfi_vec *add_cfi_vec;
@@ -274,11 +274,13 @@ add_cfi (dw_cfi_ref cfi)
}
any_cfis_emitted = true;
- if (cfi_insn != NULL)
+
+ if (add_cfi_insn != NULL)
{
- cfi_insn = emit_note_after (NOTE_INSN_CFI, cfi_insn);
- NOTE_CFI (cfi_insn) = cfi;
+ add_cfi_insn = emit_note_after (NOTE_INSN_CFI, add_cfi_insn);
+ NOTE_CFI (add_cfi_insn) = cfi;
}
+
if (add_cfi_vec != NULL)
VEC_safe_push (dw_cfi_ref, gc, *add_cfi_vec, cfi);
}
@@ -2319,7 +2321,7 @@ create_cfi_notes (void)
{
rtx pat;
- cfi_insn = PREV_INSN (insn);
+ add_cfi_insn = PREV_INSN (insn);
if (BARRIER_P (insn))
{
@@ -2342,7 +2344,7 @@ create_cfi_notes (void)
break;
case NOTE_INSN_CFA_RESTORE_STATE:
- cfi_insn = insn;
+ add_cfi_insn = insn;
dwarf2out_frame_debug_restore_state ();
break;
}
@@ -2372,13 +2374,13 @@ create_cfi_notes (void)
/* Do not separate tablejump insns from their ADDR_DIFF_VEC.
Putting the note after the VEC should be ok. */
- if (!tablejump_p (insn, NULL, &cfi_insn))
- cfi_insn = insn;
+ if (!tablejump_p (insn, NULL, &add_cfi_insn))
+ add_cfi_insn = insn;
dwarf2out_frame_debug (insn, true);
}
- cfi_insn = NULL;
+ add_cfi_insn = NULL;
}
/* Determine if we need to save and restore CFI information around this
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* [PATCH 9/9] dwarf2cfi: Generate and connect traces.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (5 preceding siblings ...)
2011-07-14 23:10 ` [PATCH 2/9] dwarf2cfi: Rename cfi_insn to add_cfi_insn Richard Henderson
@ 2011-07-14 23:16 ` Richard Henderson
2011-08-06 17:46 ` H.J. Lu
2011-07-14 23:25 ` [PATCH 7/9] dwarf2cfi: Allocate reg_saved_in_data in the heap Richard Henderson
` (3 subsequent siblings)
10 siblings, 1 reply; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:16 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
This kinda-sorta corresponds to Bernd's 007-dw2cfi patch. Certainly
the same concepts of splitting the instruction stream into extended
basic blocks is the same. This patch does a bit better job with the
documentation. Also, I'm a bit more explicit about matching things
up with the similar code from the regular CFG routines.
What's missing at this point is any attempt to use DW_CFA_remember_state.
I've deferred that for the moment because it's easy to test the state
change code across epilogues, whereas the shrink-wrapping code is not
in this tree and section switching is difficult to force.
---
gcc/dwarf2cfi.c | 792 ++++++++++++++++++++++++++++---------------------------
1 files changed, 398 insertions(+), 394 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index 9aa1208..10e5740 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -27,6 +27,7 @@ along with GCC; see the file COPYING3. If not see
#include "flags.h"
#include "rtl.h"
#include "function.h"
+#include "basic-block.h"
#include "dwarf2.h"
#include "dwarf2out.h"
#include "dwarf2asm.h"
@@ -86,34 +87,30 @@ DEF_VEC_ALLOC_O (reg_saved_in_data, heap);
/* Since we no longer have a proper CFG, we're going to create a facsimile
of one on the fly while processing the frame-related insns.
- We create dw_trace structures for each instruction trace beginning at
- at a label following a barrier (or beginning of the function), and
- ending at a barrier (or the end of the function).
+ We create dw_trace_info structures for each extended basic block beginning
+ and ending at a "save point". Save points are labels, barriers, certain
+ notes, and of course the beginning and end of the function.
As we encounter control transfer insns, we propagate the "current"
- row state across the edges to the starts of traces. If an edge goes
- to a label that is not the start of a trace, we ignore it. This
- assumes that previous compiler transformations were correct, and that
- we will reach the same row state from any source. (We can perform some
- limited validation of this assumption, but without the full CFG we
- cannot be sure of full validation coverage. It is expensive, so we
- only do so with checking enabled.)
+ row state across the edges to the starts of traces. When checking is
+ enabled, we validate that we propagate the same data from all sources.
All traces are members of the TRACE_INFO array, in the order in which
they appear in the instruction stream.
- All labels are given an LUID that indexes the LABEL_INFO array. If
- the label is the start of a trace, the TRACE pointer will be non-NULL
- and point into the TRACE_INFO array. */
+ All save points are present in the TRACE_INDEX hash, mapping the insn
+ starting a trace to the dw_trace_info describing the trace. */
typedef struct
{
- /* The label that begins the trace. This will be NULL for the first
- trace beginning at function entry. */
- rtx label;
+ /* The insn that begins the trace. */
+ rtx head;
/* The row state at the beginning and end of the trace. */
- dw_cfi_row *enter_row, *exit_row;
+ dw_cfi_row *beg_row, *end_row;
+
+ /* True if this trace immediately follows NOTE_INSN_SWITCH_TEXT_SECTIONS. */
+ bool switch_sections;
/* The following variables contain data used in interpreting frame related
expressions. These are not part of the "real" row state as defined by
@@ -147,24 +144,15 @@ typedef struct
DEF_VEC_O (dw_trace_info);
DEF_VEC_ALLOC_O (dw_trace_info, heap);
-typedef struct
-{
- dw_trace_info *trace;
-
-#ifdef ENABLE_CHECKING
- dw_cfi_row *check_row;
-#endif
-} dw_label_info;
+typedef dw_trace_info *dw_trace_info_ref;
-DEF_VEC_O (dw_label_info);
-DEF_VEC_ALLOC_O (dw_label_info, heap);
+DEF_VEC_P (dw_trace_info_ref);
+DEF_VEC_ALLOC_P (dw_trace_info_ref, heap);
/* The variables making up the pseudo-cfg, as described above. */
-#if 0
-static VEC (int, heap) *uid_luid;
-static VEC (dw_label_info, heap) *label_info;
static VEC (dw_trace_info, heap) *trace_info;
-#endif
+static VEC (dw_trace_info_ref, heap) *trace_work_list;
+static htab_t trace_index;
/* A vector of call frame insns for the CIE. */
cfi_vec cie_cfi_vec;
@@ -189,9 +177,6 @@ static dw_trace_info *cur_trace;
/* The current, i.e. most recently generated, row of the CFI table. */
static dw_cfi_row *cur_row;
-/* The row state from a preceeding DW_CFA_remember_state. */
-static dw_cfi_row *remember_row;
-
/* We delay emitting a register save until either (a) we reach the end
of the prologue or (b) the register is clobbered. This clusters
register saves so that there are fewer pc advances. */
@@ -211,9 +196,6 @@ static VEC(queued_reg_save, heap) *queued_reg_saves;
emitting this data, i.e. updating CUR_ROW, without async unwind. */
static HOST_WIDE_INT queued_args_size;
-/* True if remember_state should be emitted before following CFI directive. */
-static bool emit_cfa_remember;
-
/* True if any CFI directives were emitted at the current insn. */
static bool any_cfis_emitted;
@@ -221,11 +203,6 @@ static bool any_cfis_emitted;
static unsigned dw_stack_pointer_regnum;
static unsigned dw_frame_pointer_regnum;
\f
-
-static void dwarf2out_cfi_begin_epilogue (rtx insn);
-static void dwarf2out_frame_debug_restore_state (void);
-
-\f
/* Hook used by __throw. */
rtx
@@ -295,6 +272,53 @@ expand_builtin_init_dwarf_reg_sizes (tree address)
targetm.init_dwarf_reg_sizes_extra (address);
}
+\f
+static hashval_t
+dw_trace_info_hash (const void *ptr)
+{
+ const dw_trace_info *ti = (const dw_trace_info *) ptr;
+ return INSN_UID (ti->head);
+}
+
+static int
+dw_trace_info_eq (const void *ptr_a, const void *ptr_b)
+{
+ const dw_trace_info *a = (const dw_trace_info *) ptr_a;
+ const dw_trace_info *b = (const dw_trace_info *) ptr_b;
+ return a->head == b->head;
+}
+
+static dw_trace_info *
+get_trace_info (rtx insn)
+{
+ dw_trace_info dummy;
+ dummy.head = insn;
+ return (dw_trace_info *)
+ htab_find_with_hash (trace_index, &dummy, INSN_UID (insn));
+}
+
+static bool
+save_point_p (rtx insn)
+{
+ /* Labels, except those that are really jump tables. */
+ if (LABEL_P (insn))
+ return inside_basic_block_p (insn);
+
+ /* We split traces at the prologue/epilogue notes because those
+ are points at which the unwind info is usually stable. This
+ makes it easier to find spots with identical unwind info so
+ that we can use remember/restore_state opcodes. */
+ if (NOTE_P (insn))
+ switch (NOTE_KIND (insn))
+ {
+ case NOTE_INSN_PROLOGUE_END:
+ case NOTE_INSN_EPILOGUE_BEG:
+ return true;
+ }
+
+ return false;
+}
+
/* Divide OFF by DWARF_CIE_DATA_ALIGNMENT, asserting no remainder. */
static inline HOST_WIDE_INT
@@ -352,18 +376,6 @@ copy_cfi_row (dw_cfi_row *src)
return dst;
}
-/* Free an allocated CFI row. */
-
-static void
-free_cfi_row (dw_cfi_row *row)
-{
- if (row != NULL)
- {
- VEC_free (dw_cfi_ref, gc, row->reg_save);
- ggc_free (row);
- }
-}
-
/* Generate a new label for the CFI info to refer to. */
static char *
@@ -382,17 +394,6 @@ dwarf2out_cfi_label (void)
static void
add_cfi (dw_cfi_ref cfi)
{
- if (emit_cfa_remember)
- {
- dw_cfi_ref cfi_remember;
-
- /* Emit the state save. */
- emit_cfa_remember = false;
- cfi_remember = new_cfi ();
- cfi_remember->dw_cfi_opc = DW_CFA_remember_state;
- add_cfi (cfi_remember);
- }
-
any_cfis_emitted = true;
if (add_cfi_insn != NULL)
@@ -645,6 +646,44 @@ cfi_equal_p (dw_cfi_ref a, dw_cfi_ref b)
&a->dw_cfi_oprnd2, &b->dw_cfi_oprnd2));
}
+/* Determine if two CFI_ROW structures are identical. */
+
+static bool
+cfi_row_equal_p (dw_cfi_row *a, dw_cfi_row *b)
+{
+ size_t i, n_a, n_b, n_max;
+
+ if (a->cfa_cfi)
+ {
+ if (!cfi_equal_p (a->cfa_cfi, b->cfa_cfi))
+ return false;
+ }
+ else if (!cfa_equal_p (&a->cfa, &b->cfa))
+ return false;
+
+ if (a->args_size != b->args_size)
+ return false;
+
+ n_a = VEC_length (dw_cfi_ref, a->reg_save);
+ n_b = VEC_length (dw_cfi_ref, b->reg_save);
+ n_max = MAX (n_a, n_b);
+
+ for (i = 0; i < n_max; ++i)
+ {
+ dw_cfi_ref r_a = NULL, r_b = NULL;
+
+ if (i < n_a)
+ r_a = VEC_index (dw_cfi_ref, a->reg_save, i);
+ if (i < n_b)
+ r_b = VEC_index (dw_cfi_ref, b->reg_save, i);
+
+ if (!cfi_equal_p (r_a, r_b))
+ return false;
+ }
+
+ return true;
+}
+
/* The CFA is now calculated from NEW_CFA. Consider OLD_CFA in determining
what opcode to emit. Returns the CFI opcode to effect the change, or
NULL if NEW_CFA == OLD_CFA. */
@@ -878,179 +917,6 @@ stack_adjust_offset (const_rtx pattern, HOST_WIDE_INT cur_args_size,
return offset;
}
-/* Precomputed args_size for CODE_LABELs and BARRIERs preceeding them,
- indexed by INSN_UID. */
-
-static HOST_WIDE_INT *barrier_args_size;
-
-/* Helper function for compute_barrier_args_size. Handle one insn. */
-
-static HOST_WIDE_INT
-compute_barrier_args_size_1 (rtx insn, HOST_WIDE_INT cur_args_size,
- VEC (rtx, heap) **next)
-{
- HOST_WIDE_INT offset = 0;
- int i;
-
- if (! RTX_FRAME_RELATED_P (insn))
- {
- if (prologue_epilogue_contains (insn))
- /* Nothing */;
- else if (GET_CODE (PATTERN (insn)) == SET)
- offset = stack_adjust_offset (PATTERN (insn), cur_args_size, 0);
- else if (GET_CODE (PATTERN (insn)) == PARALLEL
- || GET_CODE (PATTERN (insn)) == SEQUENCE)
- {
- /* There may be stack adjustments inside compound insns. Search
- for them. */
- for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
- if (GET_CODE (XVECEXP (PATTERN (insn), 0, i)) == SET)
- offset += stack_adjust_offset (XVECEXP (PATTERN (insn), 0, i),
- cur_args_size, offset);
- }
- }
- else
- {
- rtx expr = find_reg_note (insn, REG_FRAME_RELATED_EXPR, NULL_RTX);
-
- if (expr)
- {
- expr = XEXP (expr, 0);
- if (GET_CODE (expr) == PARALLEL
- || GET_CODE (expr) == SEQUENCE)
- for (i = 1; i < XVECLEN (expr, 0); i++)
- {
- rtx elem = XVECEXP (expr, 0, i);
-
- if (GET_CODE (elem) == SET && !RTX_FRAME_RELATED_P (elem))
- offset += stack_adjust_offset (elem, cur_args_size, offset);
- }
- }
- }
-
-#ifndef STACK_GROWS_DOWNWARD
- offset = -offset;
-#endif
-
- cur_args_size += offset;
- if (cur_args_size < 0)
- cur_args_size = 0;
-
- if (JUMP_P (insn))
- {
- rtx dest = JUMP_LABEL (insn);
-
- if (dest)
- {
- if (barrier_args_size [INSN_UID (dest)] < 0)
- {
- barrier_args_size [INSN_UID (dest)] = cur_args_size;
- VEC_safe_push (rtx, heap, *next, dest);
- }
- }
- }
-
- return cur_args_size;
-}
-
-/* Walk the whole function and compute args_size on BARRIERs. */
-
-static void
-compute_barrier_args_size (void)
-{
- int max_uid = get_max_uid (), i;
- rtx insn;
- VEC (rtx, heap) *worklist, *next, *tmp;
-
- barrier_args_size = XNEWVEC (HOST_WIDE_INT, max_uid);
- for (i = 0; i < max_uid; i++)
- barrier_args_size[i] = -1;
-
- worklist = VEC_alloc (rtx, heap, 20);
- next = VEC_alloc (rtx, heap, 20);
- insn = get_insns ();
- barrier_args_size[INSN_UID (insn)] = 0;
- VEC_quick_push (rtx, worklist, insn);
- for (;;)
- {
- while (!VEC_empty (rtx, worklist))
- {
- rtx prev, body, first_insn;
- HOST_WIDE_INT cur_args_size;
-
- first_insn = insn = VEC_pop (rtx, worklist);
- cur_args_size = barrier_args_size[INSN_UID (insn)];
- prev = prev_nonnote_insn (insn);
- if (prev && BARRIER_P (prev))
- barrier_args_size[INSN_UID (prev)] = cur_args_size;
-
- for (; insn; insn = NEXT_INSN (insn))
- {
- if (INSN_DELETED_P (insn) || NOTE_P (insn))
- continue;
- if (BARRIER_P (insn))
- break;
-
- if (LABEL_P (insn))
- {
- if (insn == first_insn)
- continue;
- else if (barrier_args_size[INSN_UID (insn)] < 0)
- {
- barrier_args_size[INSN_UID (insn)] = cur_args_size;
- continue;
- }
- else
- {
- /* The insns starting with this label have been
- already scanned or are in the worklist. */
- break;
- }
- }
-
- body = PATTERN (insn);
- if (GET_CODE (body) == SEQUENCE)
- {
- HOST_WIDE_INT dest_args_size = cur_args_size;
- for (i = 1; i < XVECLEN (body, 0); i++)
- if (INSN_ANNULLED_BRANCH_P (XVECEXP (body, 0, 0))
- && INSN_FROM_TARGET_P (XVECEXP (body, 0, i)))
- dest_args_size
- = compute_barrier_args_size_1 (XVECEXP (body, 0, i),
- dest_args_size, &next);
- else
- cur_args_size
- = compute_barrier_args_size_1 (XVECEXP (body, 0, i),
- cur_args_size, &next);
-
- if (INSN_ANNULLED_BRANCH_P (XVECEXP (body, 0, 0)))
- compute_barrier_args_size_1 (XVECEXP (body, 0, 0),
- dest_args_size, &next);
- else
- cur_args_size
- = compute_barrier_args_size_1 (XVECEXP (body, 0, 0),
- cur_args_size, &next);
- }
- else
- cur_args_size
- = compute_barrier_args_size_1 (insn, cur_args_size, &next);
- }
- }
-
- if (VEC_empty (rtx, next))
- break;
-
- /* Swap WORKLIST with NEXT and truncate NEXT for next iteration. */
- tmp = next;
- next = worklist;
- worklist = tmp;
- VEC_truncate (rtx, next, 0);
- }
-
- VEC_free (rtx, heap, worklist);
- VEC_free (rtx, heap, next);
-}
-
/* Add a CFI to update the running total of the size of arguments
pushed onto the stack. */
@@ -1150,25 +1016,7 @@ dwarf2out_notice_stack_adjust (rtx insn, bool after_p)
return;
}
else if (BARRIER_P (insn))
- {
- /* Don't call compute_barrier_args_size () if the only
- BARRIER is at the end of function. */
- if (barrier_args_size == NULL && next_nonnote_insn (insn))
- compute_barrier_args_size ();
- if (barrier_args_size == NULL)
- offset = 0;
- else
- {
- offset = barrier_args_size[INSN_UID (insn)];
- if (offset < 0)
- offset = 0;
- }
-
- offset -= queued_args_size;
-#ifndef STACK_GROWS_DOWNWARD
- offset = -offset;
-#endif
- }
+ return;
else if (GET_CODE (PATTERN (insn)) == SET)
offset = stack_adjust_offset (PATTERN (insn), queued_args_size, 0);
else if (GET_CODE (PATTERN (insn)) == PARALLEL
@@ -2531,58 +2379,165 @@ add_cfis_to_fde (void)
}
}
-/* Scan the function and create the initial set of CFI notes. */
+/* If LABEL is the start of a trace, then initialize the state of that
+ trace from CUR_TRACE and CUR_ROW. */
static void
-create_cfi_notes (void)
+maybe_record_trace_start (rtx start, rtx origin)
{
- rtx insn;
+ dw_trace_info *ti;
+
+ /* Sync queued data before propagating to a destination,
+ lest we propagate out-of-date data. */
+ dwarf2out_flush_queued_reg_saves ();
+ dwarf2out_args_size (queued_args_size);
- for (insn = get_insns (); insn ; insn = NEXT_INSN (insn))
+ ti = get_trace_info (start);
+ gcc_assert (ti != NULL);
+
+ if (dump_file)
{
- rtx pat;
+ fprintf (dump_file, " saw edge from trace %u to %u (via %s %d)\n",
+ (unsigned)(cur_trace - VEC_address (dw_trace_info, trace_info)),
+ (unsigned)(ti - VEC_address (dw_trace_info, trace_info)),
+ (origin ? rtx_name[(int) GET_CODE (origin)] : "fallthru"),
+ (origin ? INSN_UID (origin) : 0));
+ }
- add_cfi_insn = PREV_INSN (insn);
+ if (ti->beg_row == NULL)
+ {
+ /* This is the first time we've encountered this trace. Propagate
+ state across the edge and push the trace onto the work list. */
+ ti->beg_row = copy_cfi_row (cur_row);
+ ti->cfa_store = cur_trace->cfa_store;
+ ti->cfa_temp = cur_trace->cfa_temp;
+ ti->regs_saved_in_regs = VEC_copy (reg_saved_in_data, heap,
+ cur_trace->regs_saved_in_regs);
+
+ VEC_safe_push (dw_trace_info_ref, heap, trace_work_list, ti);
+
+ if (dump_file)
+ fprintf (dump_file, "\tpush trace %u to worklist\n",
+ (unsigned)(ti - VEC_address (dw_trace_info, trace_info)));
+ }
+ else
+ {
+ /* We ought to have the same state incoming to a given trace no
+ matter how we arrive at the trace. Anything else means we've
+ got some kind of optimization error. */
+ gcc_checking_assert (cfi_row_equal_p (cur_row, ti->beg_row));
+ }
+}
- if (BARRIER_P (insn))
+/* Propagate CUR_TRACE state to the destinations implied by INSN. */
+/* ??? Sadly, this is in large part a duplicate of make_edges. */
+
+static void
+create_trace_edges (rtx insn)
+{
+ rtx tmp, lab;
+ int i, n;
+
+ if (JUMP_P (insn))
+ {
+ if (find_reg_note (insn, REG_NON_LOCAL_GOTO, NULL_RTX))
+ ;
+ else if (tablejump_p (insn, NULL, &tmp))
{
- dwarf2out_frame_debug (insn, false);
- continue;
- }
+ rtvec vec;
+
+ tmp = PATTERN (tmp);
+ vec = XVEC (tmp, GET_CODE (tmp) == ADDR_DIFF_VEC);
- if (NOTE_P (insn))
+ n = GET_NUM_ELEM (vec);
+ for (i = 0; i < n; ++i)
+ {
+ lab = XEXP (RTVEC_ELT (vec, i), 0);
+ maybe_record_trace_start (lab, insn);
+ }
+ }
+ else if (computed_jump_p (insn))
+ {
+ for (lab = forced_labels; lab; lab = XEXP (lab, 1))
+ maybe_record_trace_start (lab, insn);
+ }
+ else if (returnjump_p (insn))
+ ;
+ else if ((tmp = extract_asm_operands (PATTERN (insn))) != NULL)
{
- switch (NOTE_KIND (insn))
+ n = ASM_OPERANDS_LABEL_LENGTH (tmp);
+ for (i = 0; i < n; ++i)
{
- case NOTE_INSN_PROLOGUE_END:
- dwarf2out_flush_queued_reg_saves ();
- break;
+ lab = XEXP (ASM_OPERANDS_LABEL (tmp, i), 0);
+ maybe_record_trace_start (lab, insn);
+ }
+ }
+ else
+ {
+ lab = JUMP_LABEL (insn);
+ gcc_assert (lab != NULL);
+ maybe_record_trace_start (lab, insn);
+ }
+ }
+ else if (CALL_P (insn))
+ {
+ /* Sibling calls don't have edges inside this function. */
+ if (SIBLING_CALL_P (insn))
+ return;
- case NOTE_INSN_EPILOGUE_BEG:
-#if defined(HAVE_epilogue)
- dwarf2out_cfi_begin_epilogue (insn);
-#endif
- break;
+ /* Process non-local goto edges. */
+ if (can_nonlocal_goto (insn))
+ for (lab = nonlocal_goto_handler_labels; lab; lab = XEXP (lab, 1))
+ maybe_record_trace_start (lab, insn);
+ }
- case NOTE_INSN_CFA_RESTORE_STATE:
- add_cfi_insn = insn;
- dwarf2out_frame_debug_restore_state ();
- break;
+ /* Process EH edges. */
+ if (CALL_P (insn) || cfun->can_throw_non_call_exceptions)
+ {
+ eh_landing_pad lp = get_eh_landing_pad_from_rtx (insn);
+ if (lp)
+ maybe_record_trace_start (lp->landing_pad, insn);
+ }
+}
- case NOTE_INSN_SWITCH_TEXT_SECTIONS:
- /* In dwarf2out_switch_text_section, we'll begin a new FDE
- for the portion of the function in the alternate text
- section. The row state at the very beginning of that
- new FDE will be exactly the row state from the CIE.
- Emit whatever CFIs are necessary to make CUR_ROW current. */
- add_cfi_insn = insn;
- change_cfi_row (cie_cfi_row, cur_row);
- break;
- }
- continue;
+/* Scan the trace beginning at INSN and create the CFI notes for the
+ instructions therein. */
+
+static void
+scan_trace (dw_trace_info *trace)
+{
+ rtx insn = trace->head;
+
+ if (dump_file)
+ fprintf (dump_file, "Processing trace %u : start at %s %d\n",
+ (unsigned)(trace - VEC_address (dw_trace_info, trace_info)),
+ rtx_name[(int) GET_CODE (insn)], INSN_UID (insn));
+
+ trace->end_row = copy_cfi_row (trace->beg_row);
+
+ cur_trace = trace;
+ cur_row = trace->end_row;
+ queued_args_size = cur_row->args_size;
+
+ for (insn = NEXT_INSN (insn); insn ; insn = NEXT_INSN (insn))
+ {
+ rtx pat;
+
+ add_cfi_insn = PREV_INSN (insn);
+
+ /* Notice the end of a trace. */
+ if (BARRIER_P (insn) || save_point_p (insn))
+ {
+ dwarf2out_flush_queued_reg_saves ();
+ dwarf2out_args_size (queued_args_size);
+
+ /* Propagate across fallthru edges. */
+ if (!BARRIER_P (insn))
+ maybe_record_trace_start (insn, NULL);
+ break;
}
- if (!NONDEBUG_INSN_P (insn))
+ if (DEBUG_INSN_P (insn) || !inside_basic_block_p (insn))
continue;
pat = PATTERN (insn);
@@ -2599,9 +2554,12 @@ create_cfi_notes (void)
dwarf2out_frame_debug (XVECEXP (pat, 0, i), false);
}
- if (CALL_P (insn)
- || find_reg_note (insn, REG_CFA_FLUSH_QUEUE, NULL))
+ if (CALL_P (insn))
dwarf2out_frame_debug (insn, false);
+ else if (find_reg_note (insn, REG_CFA_FLUSH_QUEUE, NULL)
+ || (cfun->can_throw_non_call_exceptions
+ && can_throw_internal (insn)))
+ dwarf2out_flush_queued_reg_saves ();
/* Do not separate tablejump insns from their ADDR_DIFF_VEC.
Putting the note after the VEC should be ok. */
@@ -2609,106 +2567,163 @@ create_cfi_notes (void)
add_cfi_insn = insn;
dwarf2out_frame_debug (insn, true);
+
+ create_trace_edges (insn);
}
add_cfi_insn = NULL;
+ cur_row = NULL;
+ cur_trace = NULL;
}
-/* Determine if we need to save and restore CFI information around this
- epilogue. If SIBCALL is true, then this is a sibcall epilogue. If
- we do need to save/restore, then emit the save now, and insert a
- NOTE_INSN_CFA_RESTORE_STATE at the appropriate place in the stream. */
+/* Scan the function and create the initial set of CFI notes. */
static void
-dwarf2out_cfi_begin_epilogue (rtx insn)
+create_cfi_notes (void)
{
- bool saw_frp = false;
- rtx i;
+ dw_trace_info *ti;
- /* Scan forward to the return insn, noticing if there are possible
- frame related insns. */
- for (i = NEXT_INSN (insn); i ; i = NEXT_INSN (i))
- {
- if (!INSN_P (i))
- continue;
+ gcc_checking_assert (queued_reg_saves == NULL);
+ gcc_checking_assert (trace_work_list == NULL);
- /* Look for both regular and sibcalls to end the block. */
- if (returnjump_p (i))
- break;
- if (CALL_P (i) && SIBLING_CALL_P (i))
- break;
+ /* Always begin at the entry trace. */
+ ti = VEC_index (dw_trace_info, trace_info, 0);
+ scan_trace (ti);
- if (GET_CODE (PATTERN (i)) == SEQUENCE)
- {
- int idx;
- rtx seq = PATTERN (i);
-
- if (returnjump_p (XVECEXP (seq, 0, 0)))
- break;
- if (CALL_P (XVECEXP (seq, 0, 0))
- && SIBLING_CALL_P (XVECEXP (seq, 0, 0)))
- break;
-
- for (idx = 0; idx < XVECLEN (seq, 0); idx++)
- if (RTX_FRAME_RELATED_P (XVECEXP (seq, 0, idx)))
- saw_frp = true;
- }
-
- if (RTX_FRAME_RELATED_P (i))
- saw_frp = true;
+ while (!VEC_empty (dw_trace_info_ref, trace_work_list))
+ {
+ ti = VEC_pop (dw_trace_info_ref, trace_work_list);
+ scan_trace (ti);
}
- /* If the port doesn't emit epilogue unwind info, we don't need a
- save/restore pair. */
- if (!saw_frp)
- return;
+ VEC_free (queued_reg_save, heap, queued_reg_saves);
+ VEC_free (dw_trace_info_ref, heap, trace_work_list);
+}
- /* Otherwise, search forward to see if the return insn was the last
- basic block of the function. If so, we don't need save/restore. */
- gcc_assert (i != NULL);
- i = next_real_insn (i);
- if (i == NULL)
- return;
+/* Insert CFI notes between traces to properly change state between them. */
+/* ??? TODO: Make use of remember/restore_state. */
+
+static void
+connect_traces (void)
+{
+ unsigned i, n = VEC_length (dw_trace_info, trace_info);
+ dw_trace_info *prev_ti, *ti;
+
+ prev_ti = VEC_index (dw_trace_info, trace_info, 0);
- /* Insert the restore before that next real insn in the stream, and before
- a potential NOTE_INSN_EPILOGUE_BEG -- we do need these notes to be
- properly nested. This should be after any label or alignment. This
- will be pushed into the CFI stream by the function below. */
- while (1)
+ for (i = 1; i < n; ++i, prev_ti = ti)
{
- rtx p = PREV_INSN (i);
- if (!NOTE_P (p))
- break;
- if (NOTE_KIND (p) == NOTE_INSN_BASIC_BLOCK)
- break;
- i = p;
- }
- emit_note_before (NOTE_INSN_CFA_RESTORE_STATE, i);
+ dw_cfi_row *old_row;
+
+ ti = VEC_index (dw_trace_info, trace_info, i);
- emit_cfa_remember = true;
+ /* We must have both queued and processed every trace. */
+ gcc_assert (ti->beg_row && ti->end_row);
+
+ /* In dwarf2out_switch_text_section, we'll begin a new FDE
+ for the portion of the function in the alternate text
+ section. The row state at the very beginning of that
+ new FDE will be exactly the row state from the CIE. */
+ if (ti->switch_sections)
+ old_row = cie_cfi_row;
+ else
+ old_row = prev_ti->end_row;
- /* And emulate the state save. */
- gcc_assert (remember_row == NULL);
- remember_row = copy_cfi_row (cur_row);
+ add_cfi_insn = ti->head;
+ change_cfi_row (old_row, ti->beg_row);
+
+ if (dump_file && add_cfi_insn != ti->head)
+ {
+ rtx note;
+
+ fprintf (dump_file, "Fixup between trace %u and %u:\n", i - 1, i);
+
+ note = ti->head;
+ do
+ {
+ note = NEXT_INSN (note);
+ gcc_assert (NOTE_P (note) && NOTE_KIND (note) == NOTE_INSN_CFI);
+ output_cfi_directive (dump_file, NOTE_CFI (note));
+ }
+ while (note != add_cfi_insn);
+ }
+ }
}
-/* A "subroutine" of dwarf2out_cfi_begin_epilogue. Emit the restore
- required. */
+/* Set up the pseudo-cfg of instruction traces, as described at the
+ block comment at the top of the file. */
static void
-dwarf2out_frame_debug_restore_state (void)
+create_pseudo_cfg (void)
{
- dw_cfi_ref cfi = new_cfi ();
+ bool saw_barrier, switch_sections;
+ dw_trace_info *ti;
+ rtx insn;
+ unsigned i;
+
+ /* The first trace begins at the start of the function,
+ and begins with the CIE row state. */
+ trace_info = VEC_alloc (dw_trace_info, heap, 16);
+ ti = VEC_quick_push (dw_trace_info, trace_info, NULL);
+
+ memset (ti, 0, sizeof (*ti));
+ ti->head = get_insns ();
+ ti->beg_row = cie_cfi_row;
+ ti->cfa_store = cie_cfi_row->cfa;
+ ti->cfa_temp.reg = INVALID_REGNUM;
+ if (cie_return_save)
+ VEC_safe_push (reg_saved_in_data, heap,
+ ti->regs_saved_in_regs, cie_return_save);
- cfi->dw_cfi_opc = DW_CFA_restore_state;
- add_cfi (cfi);
+ /* Walk all the insns, collecting start of trace locations. */
+ saw_barrier = false;
+ switch_sections = false;
+ for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
+ {
+ if (BARRIER_P (insn))
+ saw_barrier = true;
+ else if (NOTE_P (insn)
+ && NOTE_KIND (insn) == NOTE_INSN_SWITCH_TEXT_SECTIONS)
+ {
+ /* We should have just seen a barrier. */
+ gcc_assert (saw_barrier);
+ switch_sections = true;
+ }
+ /* Watch out for save_point notes between basic blocks.
+ In particular, a note after a barrier. Do not record these,
+ delaying trace creation until the label. */
+ else if (save_point_p (insn)
+ && (LABEL_P (insn) || !saw_barrier))
+ {
+ ti = VEC_safe_push (dw_trace_info, heap, trace_info, NULL);
+ memset (ti, 0, sizeof (*ti));
+ ti->head = insn;
+ ti->switch_sections = switch_sections;
+
+ saw_barrier = false;
+ switch_sections = false;
+ }
+ }
+
+ /* Create the trace index after we've finished building trace_info,
+ avoiding stale pointer problems due to reallocation. */
+ trace_index = htab_create (16, dw_trace_info_hash, dw_trace_info_eq, NULL);
+ FOR_EACH_VEC_ELT (dw_trace_info, trace_info, i, ti)
+ {
+ void **slot;
+
+ if (dump_file)
+ fprintf (dump_file, "Creating trace %u : start at %s %d%s\n", i,
+ rtx_name[(int) GET_CODE (ti->head)], INSN_UID (ti->head),
+ ti->switch_sections ? " (section switch)" : "");
- gcc_assert (remember_row != NULL);
- free_cfi_row (cur_row);
- cur_row = remember_row;
- remember_row = NULL;
+ slot = htab_find_slot_with_hash (trace_index, ti,
+ INSN_UID (ti->head), INSERT);
+ gcc_assert (*slot == NULL);
+ *slot = (void *) ti;
+ }
}
-\f
+
/* Record the initial position of the return address. RTL is
INCOMING_RETURN_ADDR_RTX. */
@@ -2832,42 +2847,31 @@ create_cie_data (void)
static unsigned int
execute_dwarf2_frame (void)
{
- dw_trace_info dummy_trace;
-
- gcc_checking_assert (queued_reg_saves == NULL);
-
/* The first time we're called, compute the incoming frame state. */
if (cie_cfi_vec == NULL)
create_cie_data ();
- memset (&dummy_trace, 0, sizeof(dummy_trace));
- cur_trace = &dummy_trace;
-
- /* Set up state for generating call frame debug info. */
- cur_row = copy_cfi_row (cie_cfi_row);
- if (cie_return_save)
- VEC_safe_push (reg_saved_in_data, heap,
- cur_trace->regs_saved_in_regs, cie_return_save);
-
- cur_trace->cfa_store = cur_row->cfa;
- cur_trace->cfa_temp.reg = INVALID_REGNUM;
- queued_args_size = 0;
-
dwarf2out_alloc_current_fde ();
+ create_pseudo_cfg ();
+
/* Do the work. */
create_cfi_notes ();
+ connect_traces ();
add_cfis_to_fde ();
- /* Reset all function-specific information, particularly for GC. */
- XDELETEVEC (barrier_args_size);
- barrier_args_size = NULL;
- VEC_free (reg_saved_in_data, heap, cur_trace->regs_saved_in_regs);
- VEC_free (queued_reg_save, heap, queued_reg_saves);
+ /* Free all the data we allocated. */
+ {
+ size_t i;
+ dw_trace_info *ti;
- free_cfi_row (cur_row);
- cur_row = NULL;
- cur_trace = NULL;
+ FOR_EACH_VEC_ELT (dw_trace_info, trace_info, i, ti)
+ VEC_free (reg_saved_in_data, heap, ti->regs_saved_in_regs);
+ }
+ VEC_free (dw_trace_info, heap, trace_info);
+
+ htab_delete (trace_index);
+ trace_index = NULL;
return 0;
}
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* Re: [PATCH 9/9] dwarf2cfi: Generate and connect traces.
2011-07-14 23:16 ` [PATCH 9/9] dwarf2cfi: Generate and connect traces Richard Henderson
@ 2011-08-06 17:46 ` H.J. Lu
0 siblings, 0 replies; 21+ messages in thread
From: H.J. Lu @ 2011-08-06 17:46 UTC (permalink / raw)
To: Richard Henderson; +Cc: bernds, gcc-patches
On Thu, Jul 14, 2011 at 4:07 PM, Richard Henderson <rth@redhat.com> wrote:
> This kinda-sorta corresponds to Bernd's 007-dw2cfi patch. Certainly
> the same concepts of splitting the instruction stream into extended
> basic blocks is the same. This patch does a bit better job with the
> documentation. Also, I'm a bit more explicit about matching things
> up with the similar code from the regular CFG routines.
>
> What's missing at this point is any attempt to use DW_CFA_remember_state.
> I've deferred that for the moment because it's easy to test the state
> change code across epilogues, whereas the shrink-wrapping code is not
> in this tree and section switching is difficult to force.
This caused:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49994
--
H.J.
^ permalink raw reply [flat|nested] 21+ messages in thread
* [PATCH 7/9] dwarf2cfi: Allocate reg_saved_in_data in the heap.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (6 preceding siblings ...)
2011-07-14 23:16 ` [PATCH 9/9] dwarf2cfi: Generate and connect traces Richard Henderson
@ 2011-07-14 23:25 ` Richard Henderson
2011-07-15 6:09 ` [PATCH 5/9] dwarf2cfi: Remove dw_cfi_row_ref typedef Richard Henderson
` (2 subsequent siblings)
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-14 23:25 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
---
gcc/dwarf2cfi.c | 19 ++++++++++---------
1 files changed, 10 insertions(+), 9 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index a800cb4..1d6413f 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -1109,13 +1109,13 @@ typedef struct GTY(()) reg_saved_in_data {
} reg_saved_in_data;
DEF_VEC_O (reg_saved_in_data);
-DEF_VEC_ALLOC_O (reg_saved_in_data, gc);
+DEF_VEC_ALLOC_O (reg_saved_in_data, heap);
/* A set of registers saved in other registers. This is implemented as
a flat array because it normally contains zero or 1 entry, depending
on the target. IA-64 is the big spender here, using a maximum of
5 entries. */
-static GTY(()) VEC(reg_saved_in_data, gc) *regs_saved_in_regs;
+static VEC(reg_saved_in_data, heap) *regs_saved_in_regs;
static GTY(()) reg_saved_in_data *cie_return_save;
@@ -1161,7 +1161,7 @@ record_reg_saved_in_reg (rtx dest, rtx src)
if (dest == NULL)
return;
- elt = VEC_safe_push(reg_saved_in_data, gc, regs_saved_in_regs, NULL);
+ elt = VEC_safe_push(reg_saved_in_data, heap, regs_saved_in_regs, NULL);
elt->orig_reg = src;
elt->saved_in_reg = dest;
}
@@ -2699,6 +2699,9 @@ initial_return_save (rtx rtl)
static unsigned int
execute_dwarf2_frame (void)
{
+ gcc_checking_assert (queued_reg_saves == NULL);
+ gcc_checking_assert (regs_saved_in_regs == NULL);
+
/* The first time we're called, compute the incoming frame state. */
if (cie_cfi_vec == NULL)
{
@@ -2737,7 +2740,7 @@ execute_dwarf2_frame (void)
cie_return_save = ggc_alloc_reg_saved_in_data ();
*cie_return_save = *VEC_index (reg_saved_in_data,
regs_saved_in_regs, 0);
- regs_saved_in_regs = NULL;
+ VEC_pop (reg_saved_in_data, regs_saved_in_regs);
break;
default:
gcc_unreachable ();
@@ -2748,12 +2751,10 @@ execute_dwarf2_frame (void)
}
/* Set up state for generating call frame debug info. */
- gcc_checking_assert (queued_reg_saves == NULL);
- gcc_checking_assert (regs_saved_in_regs == NULL);
-
cur_row = copy_cfi_row (cie_cfi_row);
if (cie_return_save)
- VEC_safe_push (reg_saved_in_data, gc, regs_saved_in_regs, cie_return_save);
+ VEC_safe_push (reg_saved_in_data, heap,
+ regs_saved_in_regs, cie_return_save);
cfa_store = cur_row->cfa;
args_size = 0;
@@ -2770,7 +2771,7 @@ execute_dwarf2_frame (void)
/* Reset all function-specific information, particularly for GC. */
XDELETEVEC (barrier_args_size);
barrier_args_size = NULL;
- regs_saved_in_regs = NULL;
+ VEC_free (reg_saved_in_data, heap, regs_saved_in_regs);
VEC_free (queued_reg_save, heap, queued_reg_saves);
free_cfi_row (cur_row);
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* [PATCH 5/9] dwarf2cfi: Remove dw_cfi_row_ref typedef.
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (7 preceding siblings ...)
2011-07-14 23:25 ` [PATCH 7/9] dwarf2cfi: Allocate reg_saved_in_data in the heap Richard Henderson
@ 2011-07-15 6:09 ` Richard Henderson
2011-07-15 23:21 ` [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
2011-07-24 8:23 ` Richard Henderson
10 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-15 6:09 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
---
gcc/dwarf2cfi.c | 23 +++++++++++------------
1 files changed, 11 insertions(+), 12 deletions(-)
diff --git a/gcc/dwarf2cfi.c b/gcc/dwarf2cfi.c
index 745e137..51fb824 100644
--- a/gcc/dwarf2cfi.c
+++ b/gcc/dwarf2cfi.c
@@ -74,14 +74,13 @@ typedef struct GTY(()) dw_cfi_row_struct
HOST_WIDE_INT args_size;
} dw_cfi_row;
-typedef dw_cfi_row *dw_cfi_row_ref;
\f
/* A vector of call frame insns for the CIE. */
cfi_vec cie_cfi_vec;
/* The state of the first row of the FDE table, which includes the
state provided by the CIE. */
-static GTY(()) dw_cfi_row_ref cie_cfi_row;
+static GTY(()) dw_cfi_row *cie_cfi_row;
static GTY(()) unsigned long dwarf2out_cfi_label_num;
@@ -209,10 +208,10 @@ new_cfi (void)
/* Return a newly allocated CFI row, with no defined data. */
-static dw_cfi_row_ref
+static dw_cfi_row *
new_cfi_row (void)
{
- dw_cfi_row_ref row = ggc_alloc_cleared_dw_cfi_row ();
+ dw_cfi_row *row = ggc_alloc_cleared_dw_cfi_row ();
row->cfa.reg = INVALID_REGNUM;
@@ -221,10 +220,10 @@ new_cfi_row (void)
/* Return a copy of an existing CFI row. */
-static dw_cfi_row_ref
-copy_cfi_row (dw_cfi_row_ref src)
+static dw_cfi_row *
+copy_cfi_row (dw_cfi_row *src)
{
- dw_cfi_row_ref dst = ggc_alloc_dw_cfi_row ();
+ dw_cfi_row *dst = ggc_alloc_dw_cfi_row ();
*dst = *src;
dst->reg_save = VEC_copy (dw_cfi_ref, gc, src->reg_save);
@@ -235,7 +234,7 @@ copy_cfi_row (dw_cfi_row_ref src)
/* Free an allocated CFI row. */
static void
-free_cfi_row (dw_cfi_row_ref row)
+free_cfi_row (dw_cfi_row *row)
{
if (row != NULL)
{
@@ -311,7 +310,7 @@ add_cfi_restore (unsigned reg)
that the register column is no longer saved. */
static void
-update_row_reg_save (dw_cfi_row_ref row, unsigned column, dw_cfi_ref cfi)
+update_row_reg_save (dw_cfi_row *row, unsigned column, dw_cfi_ref cfi)
{
if (VEC_length (dw_cfi_ref, row->reg_save) <= column)
VEC_safe_grow_cleared (dw_cfi_ref, gc, row->reg_save, column + 1);
@@ -466,10 +465,10 @@ lookup_cfa_1 (dw_cfi_ref cfi, dw_cfa_location *loc, dw_cfa_location *remember)
}
/* The current, i.e. most recently generated, row of the CFI table. */
-static dw_cfi_row_ref cur_row;
+static dw_cfi_row *cur_row;
/* The row state from a preceeding DW_CFA_remember_state. */
-static dw_cfi_row_ref remember_row;
+static dw_cfi_row *remember_row;
/* The register used for saving registers to the stack, and its offset
from the CFA. */
@@ -2316,7 +2315,7 @@ dwarf2out_frame_debug (rtx insn, bool after_p)
/* Emit CFI info to change the state from OLD_ROW to NEW_ROW. */
static void
-change_cfi_row (dw_cfi_row_ref old_row, dw_cfi_row_ref new_row)
+change_cfi_row (dw_cfi_row *old_row, dw_cfi_row *new_row)
{
size_t i, n_old, n_new, n_max;
dw_cfi_ref cfi;
--
1.7.6
^ permalink raw reply [flat|nested] 21+ messages in thread* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (8 preceding siblings ...)
2011-07-15 6:09 ` [PATCH 5/9] dwarf2cfi: Remove dw_cfi_row_ref typedef Richard Henderson
@ 2011-07-15 23:21 ` Richard Henderson
2011-07-16 4:09 ` Bernd Schmidt
2011-07-24 8:23 ` Richard Henderson
10 siblings, 1 reply; 21+ messages in thread
From: Richard Henderson @ 2011-07-15 23:21 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
On 07/14/2011 04:07 PM, Richard Henderson wrote:
> This finally brings us to something that can support shrink-wrapping.
> As mentioned in the description of the last patch, this is 95% of
> what Bernd had in his last 007-dw2cfg patch, except for the remember/
> restore_state stuff. And hopefully with better comments.
>
> This is the first version of this that has actually made it into
> stage3 bootstrap on x86_64, so it isn't well tested yet. This just
> happens to coincide with the end of my work day, and it's been a while
> since I've shared state, so I thought I'd post for overnight review.
>
> The complete tree is available at
>
> git://repo.or.cz/gcc/rth.git rth/cfi-pass
I've fixed a few minor bugs (mostly silly typos) and pushed the
update to the external repo.
All of the x86_64 regressions are fixed except for
-freorder-blocks-and-partition vs exception handling.
Which is Very Broken at a fundamental level.
I guess I'll be re-writing all that next...
r~
^ permalink raw reply [flat|nested] 21+ messages in thread* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-07-15 23:21 ` [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
@ 2011-07-16 4:09 ` Bernd Schmidt
2011-07-16 6:07 ` Richard Henderson
0 siblings, 1 reply; 21+ messages in thread
From: Bernd Schmidt @ 2011-07-16 4:09 UTC (permalink / raw)
To: Richard Henderson; +Cc: gcc-patches
On 07/16/11 01:08, Richard Henderson wrote:
> On 07/14/2011 04:07 PM, Richard Henderson wrote:
>> This finally brings us to something that can support shrink-wrapping.
>> As mentioned in the description of the last patch, this is 95% of
>> what Bernd had in his last 007-dw2cfg patch, except for the remember/
>> restore_state stuff. And hopefully with better comments.
>>
>> This is the first version of this that has actually made it into
>> stage3 bootstrap on x86_64, so it isn't well tested yet. This just
>> happens to coincide with the end of my work day, and it's been a while
>> since I've shared state, so I thought I'd post for overnight review.
>>
>> The complete tree is available at
>>
>> git://repo.or.cz/gcc/rth.git rth/cfi-pass
>
> I've fixed a few minor bugs (mostly silly typos) and pushed the
> update to the external repo.
>
> All of the x86_64 regressions are fixed except for
> -freorder-blocks-and-partition vs exception handling.
> Which is Very Broken at a fundamental level.
Thanks again for working on this.
What's wrong with -freorder-blocks-and-partition? Something preexisting,
or introduced with these changes?
Bernd
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-07-16 4:09 ` Bernd Schmidt
@ 2011-07-16 6:07 ` Richard Henderson
0 siblings, 0 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-16 6:07 UTC (permalink / raw)
To: Bernd Schmidt; +Cc: gcc-patches
On 07/15/2011 04:24 PM, Bernd Schmidt wrote:
> What's wrong with -freorder-blocks-and-partition? Something preexisting,
> or introduced with these changes?
Pre-existing.
The .gcc_except_table format includes a encoded displacement from
a call site to a handler. We cannot represent this displacement
when the handler and the call site are in different sections.
There is a weak attempt at fixing up this situation in except.c,
convert_to_eh_region_ranges, but (1) the exception data is not
updated, and more importantly, (2) the code that is generated
violates the constraints that are assumed for the exception_receiver
and nonlocal_goto_receiver named patterns. In particular, targets
like alpha and mips that want to re-compute the GP from some
kind of pc-relative relocation will compute the wrong GP.
The problem appears in the dwarf2 pass only because of (1), in
that when we validate that all extended basic blocks have had
unwind info propagated into them, we find that there are blocks
that are unvisited.
All this cross-segment fixup stuff should have been handled in
pass_partition_blocks, not delayed until it's too late to do
the right thing.
And of course pass_partition_blocks is... well, let's just say
it's due for a bit of maintenance.
r~
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-07-14 23:10 [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
` (9 preceding siblings ...)
2011-07-15 23:21 ` [RFC PATCH 0/9] CFG aware dwarf2 cfi generation Richard Henderson
@ 2011-07-24 8:23 ` Richard Henderson
2011-07-24 8:24 ` Bernd Schmidt
2011-08-03 20:24 ` Jan Hubicka
10 siblings, 2 replies; 21+ messages in thread
From: Richard Henderson @ 2011-07-24 8:23 UTC (permalink / raw)
To: bernds; +Cc: gcc-patches
On 07/14/2011 04:07 PM, Richard Henderson wrote:
> This finally brings us to something that can support shrink-wrapping.
> As mentioned in the description of the last patch, this is 95% of
> what Bernd had in his last 007-dw2cfg patch, except for the remember/
> restore_state stuff. And hopefully with better comments.
>
> This is the first version of this that has actually made it into
> stage3 bootstrap on x86_64, so it isn't well tested yet. This just
> happens to coincide with the end of my work day, and it's been a while
> since I've shared state, so I thought I'd post for overnight review.
I've now committed this entire patch series.
I will work on generating DW_CFA_remember_state markers next week,
but what's here now should support anything that your shrink-wrapping
patches can throw at it.
Where are we at with the review of the actual shrink-wrap patch set?
r~
^ permalink raw reply [flat|nested] 21+ messages in thread* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-07-24 8:23 ` Richard Henderson
@ 2011-07-24 8:24 ` Bernd Schmidt
2011-08-03 20:24 ` Jan Hubicka
1 sibling, 0 replies; 21+ messages in thread
From: Bernd Schmidt @ 2011-07-24 8:24 UTC (permalink / raw)
To: Richard Henderson; +Cc: gcc-patches
On 07/23/11 22:56, Richard Henderson wrote:
> Where are we at with the review of the actual shrink-wrap patch set?
Richard S. has started reviewing it, and I'm trying to break out some
more preliminary bits and pieces.
Bernd
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-07-24 8:23 ` Richard Henderson
2011-07-24 8:24 ` Bernd Schmidt
@ 2011-08-03 20:24 ` Jan Hubicka
2011-08-03 20:26 ` Richard Henderson
2011-08-04 1:08 ` Andi Kleen
1 sibling, 2 replies; 21+ messages in thread
From: Jan Hubicka @ 2011-08-03 20:24 UTC (permalink / raw)
To: Richard Henderson; +Cc: bernds, gcc-patches
> On 07/14/2011 04:07 PM, Richard Henderson wrote:
> > This finally brings us to something that can support shrink-wrapping.
> > As mentioned in the description of the last patch, this is 95% of
> > what Bernd had in his last 007-dw2cfg patch, except for the remember/
> > restore_state stuff. And hopefully with better comments.
> >
> > This is the first version of this that has actually made it into
> > stage3 bootstrap on x86_64, so it isn't well tested yet. This just
> > happens to coincide with the end of my work day, and it's been a while
> > since I've shared state, so I thought I'd post for overnight review.
>
> I've now committed this entire patch series.
>
> I will work on generating DW_CFA_remember_state markers next week,
Cool, will this also help to handle alternate entry points, so we can move ahead
on this area we got stuck years ago? (i.e. add support for alternate entry points on
i386 skipping IP pointer load in PIC mode/using register passing conventions)
Honza
> but what's here now should support anything that your shrink-wrapping
> patches can throw at it.
>
> Where are we at with the review of the actual shrink-wrap patch set?
>
>
> r~
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-08-03 20:24 ` Jan Hubicka
@ 2011-08-03 20:26 ` Richard Henderson
2011-08-03 20:33 ` Jan Hubicka
2011-08-04 1:08 ` Andi Kleen
1 sibling, 1 reply; 21+ messages in thread
From: Richard Henderson @ 2011-08-03 20:26 UTC (permalink / raw)
To: Jan Hubicka; +Cc: bernds, gcc-patches
On 08/03/2011 01:24 PM, Jan Hubicka wrote:
> Cool, will this also help to handle alternate entry points, so we can move ahead
> on this area we got stuck years ago? (i.e. add support for alternate entry points on
> i386 skipping IP pointer load in PIC mode/using register passing conventions)
I honestly don't remember what happened with the alternate entry points.
But if it was unwind info, then yes, this will help.
r~
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-08-03 20:26 ` Richard Henderson
@ 2011-08-03 20:33 ` Jan Hubicka
0 siblings, 0 replies; 21+ messages in thread
From: Jan Hubicka @ 2011-08-03 20:33 UTC (permalink / raw)
To: Richard Henderson; +Cc: Jan Hubicka, bernds, gcc-patches
> On 08/03/2011 01:24 PM, Jan Hubicka wrote:
> > Cool, will this also help to handle alternate entry points, so we can move ahead
> > on this area we got stuck years ago? (i.e. add support for alternate entry points on
> > i386 skipping IP pointer load in PIC mode/using register passing conventions)
>
> I honestly don't remember what happened with the alternate entry points.
> But if it was unwind info, then yes, this will help.
Well, as I remember, the basic infrastructure that allowed to introduce alternate entry points
late in the compilation (i.e. during prologue/epilogue generation) is in. We just got stuck precisely
on making it working with the unwind info. (as I recall years back, Ihad patches that allowed us
to skip the IP load in PIC mode and planned to follow with the register calling conventions).
This is the -fPIC patch.
http://web.archiveorange.com/archive/v/iv9U0XRCHosZ5bDh6Z6Q
and this is apparently where we got stuck back then.
http://web.archiveorange.com/archive/v/iv9U0byrEj0gzOKGqTtx
Honza
>
>
> r~
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-08-03 20:24 ` Jan Hubicka
2011-08-03 20:26 ` Richard Henderson
@ 2011-08-04 1:08 ` Andi Kleen
2011-08-04 13:38 ` Jan Hubicka
1 sibling, 1 reply; 21+ messages in thread
From: Andi Kleen @ 2011-08-04 1:08 UTC (permalink / raw)
To: Jan Hubicka; +Cc: Richard Henderson, bernds, gcc-patches
Jan Hubicka <hubicka@ucw.cz> writes:
>
> Cool, will this also help to handle alternate entry points, so we can move ahead
> on this area we got stuck years ago? (i.e. add support for alternate entry points on
> i386 skipping IP pointer load in PIC mode/using register passing conventions)
Also alternative entry points to skip x87 in favour of SSE
register passing for FP would be really nice.
-Andi
--
ak@linux.intel.com -- Speaking for myself only
^ permalink raw reply [flat|nested] 21+ messages in thread
* Re: [RFC PATCH 0/9] CFG aware dwarf2 cfi generation
2011-08-04 1:08 ` Andi Kleen
@ 2011-08-04 13:38 ` Jan Hubicka
0 siblings, 0 replies; 21+ messages in thread
From: Jan Hubicka @ 2011-08-04 13:38 UTC (permalink / raw)
To: Andi Kleen; +Cc: Jan Hubicka, Richard Henderson, bernds, gcc-patches, tglek
> Jan Hubicka <hubicka@ucw.cz> writes:
> >
> > Cool, will this also help to handle alternate entry points, so we can move ahead
> > on this area we got stuck years ago? (i.e. add support for alternate entry points on
> > i386 skipping IP pointer load in PIC mode/using register passing conventions)
>
> Also alternative entry points to skip x87 in favour of SSE
> register passing for FP would be really nice.
Yep, there is quite some potential in this on x86. On x86-64 also stack
alignment prologues could be eliminated.
I guess the PIC tricks could do wonders for Mozilla. Additionally once this
works, we can move ahead with alternate entry points at gimple level possibly
re-implementing thunks/ctor clonning using them.
So if we finally get past the unwind info issues, I could start poking about
getting the PIC codegen working as a first experiment.
Honza
>
> -Andi
>
> --
> ak@linux.intel.com -- Speaking for myself only
^ permalink raw reply [flat|nested] 21+ messages in thread