[PATCH 4/8] [i386] Modify ix86_save_reg to optionally omit stub-managed registers

[Daniel Santos <daniel.santos@pobox.com>]

Adds HARD_REG_SET stub_managed_regs to track registers that will be
managed by the pro/epilogue stubs for the function.

Adds a third parameter bool ignore_outlined to ix86_save_reg to specify
rather or not the count should include registers marked in
stub_managed_regs.

Signed-off-by: Daniel Santos <daniel.santos@pobox.com>
---
 gcc/config/i386/i386.c | 31 ++++++++++++++++++++-----------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 6449fbb42bb..d52533103f5 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -12463,6 +12463,10 @@ ix86_hard_regno_scratch_ok (unsigned int regno)
 	      && df_regs_ever_live_p (regno)));
 }
 
+/* Registers who's save & restore will be managed by stubs called from
+   pro/epilogue.  */
+static HARD_REG_SET GTY(()) stub_managed_regs;
+
 /* Return true if register class CL should be an additional allocno
    class.  */
 
@@ -12475,7 +12479,7 @@ ix86_additional_allocno_class_p (reg_class_t cl)
 /* Return TRUE if we need to save REGNO.  */
 
 static bool
-ix86_save_reg (unsigned int regno, bool maybe_eh_return)
+ix86_save_reg (unsigned int regno, bool maybe_eh_return, bool ignore_outlined)
 {
   /* If there are no caller-saved registers, we preserve all registers,
      except for MMX and x87 registers which aren't supported when saving
@@ -12543,6 +12547,10 @@ ix86_save_reg (unsigned int regno, bool maybe_eh_return)
 	}
     }
 
+  if (ignore_outlined && cfun->machine->outline_ms_sysv
+      && in_hard_reg_set_p (stub_managed_regs, DImode, regno))
+    return false;
+
   if (crtl->drap_reg
       && regno == REGNO (crtl->drap_reg)
       && !cfun->machine->no_drap_save_restore)
@@ -12563,7 +12571,7 @@ ix86_nsaved_regs (void)
   int regno;
 
   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
-    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true))
+    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true, true))
       nregs ++;
   return nregs;
 }
@@ -12579,7 +12587,7 @@ ix86_nsaved_sseregs (void)
   if (!TARGET_64BIT_MS_ABI)
     return 0;
   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
-    if (SSE_REGNO_P (regno) && ix86_save_reg (regno, true))
+    if (SSE_REGNO_P (regno) && ix86_save_reg (regno, true, true))
       nregs ++;
   return nregs;
 }
@@ -12659,6 +12667,7 @@ ix86_compute_frame_layout (struct ix86_frame *frame)
 
   frame->nregs = ix86_nsaved_regs ();
   frame->nsseregs = ix86_nsaved_sseregs ();
+  CLEAR_HARD_REG_SET (stub_managed_regs);
 
   /* 64-bit MS ABI seem to require stack alignment to be always 16,
      except for function prologues, leaf functions and when the defult
@@ -13049,7 +13058,7 @@ ix86_emit_save_regs (void)
   rtx_insn *insn;
 
   for (regno = FIRST_PSEUDO_REGISTER - 1; regno-- > 0; )
-    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true))
+    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true, true))
       {
 	insn = emit_insn (gen_push (gen_rtx_REG (word_mode, regno)));
 	RTX_FRAME_RELATED_P (insn) = 1;
@@ -13139,7 +13148,7 @@ ix86_emit_save_regs_using_mov (HOST_WIDE_INT cfa_offset)
   unsigned int regno;
 
   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
-    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true))
+    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, true, true))
       {
         ix86_emit_save_reg_using_mov (word_mode, regno, cfa_offset);
 	cfa_offset -= UNITS_PER_WORD;
@@ -13154,7 +13163,7 @@ ix86_emit_save_sse_regs_using_mov (HOST_WIDE_INT cfa_offset)
   unsigned int regno;
 
   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
-    if (SSE_REGNO_P (regno) && ix86_save_reg (regno, true))
+    if (SSE_REGNO_P (regno) && ix86_save_reg (regno, true, true))
       {
 	ix86_emit_save_reg_using_mov (V4SFmode, regno, cfa_offset);
 	cfa_offset -= GET_MODE_SIZE (V4SFmode);
@@ -13538,13 +13547,13 @@ get_scratch_register_on_entry (struct scratch_reg *sr)
 	       && !static_chain_p
 	       && drap_regno != CX_REG)
 	regno = CX_REG;
-      else if (ix86_save_reg (BX_REG, true))
+      else if (ix86_save_reg (BX_REG, true, false))
 	regno = BX_REG;
       /* esi is the static chain register.  */
       else if (!(regparm == 3 && static_chain_p)
-	       && ix86_save_reg (SI_REG, true))
+	       && ix86_save_reg (SI_REG, true, false))
 	regno = SI_REG;
-      else if (ix86_save_reg (DI_REG, true))
+      else if (ix86_save_reg (DI_REG, true, false))
 	regno = DI_REG;
       else
 	{
@@ -14648,7 +14657,7 @@ ix86_emit_restore_regs_using_mov (HOST_WIDE_INT cfa_offset,
   unsigned int regno;
 
   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
-    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, maybe_eh_return))
+    if (GENERAL_REGNO_P (regno) && ix86_save_reg (regno, maybe_eh_return, true))
       {
 	rtx reg = gen_rtx_REG (word_mode, regno);
 	rtx mem;
@@ -14687,7 +14696,7 @@ ix86_emit_restore_sse_regs_using_mov (HOST_WIDE_INT cfa_offset,
   unsigned int regno;
 
   for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
-    if (SSE_REGNO_P (regno) && ix86_save_reg (regno, maybe_eh_return))
+    if (SSE_REGNO_P (regno) && ix86_save_reg (regno, maybe_eh_return, true))
       {
 	rtx reg = gen_rtx_REG (V4SFmode, regno);
 	rtx mem;
-- 
2.11.0