* [binutils-gdb] LoongArch: Add -mignore-start-align option
@ 2024-04-20 4:11 liu & zhensong
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From: liu & zhensong @ 2024-04-20 4:11 UTC (permalink / raw)
To: binutils-cvs
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=20eee7540b9f2615f7661393756fec0bb62a1495
commit 20eee7540b9f2615f7661393756fec0bb62a1495
Author: mengqinggang <mengqinggang@loongson.cn>
Date: Sun Apr 7 16:34:42 2024 +0800
LoongArch: Add -mignore-start-align option
Ignore .align at the start of a section may result in misalignment when
partial linking. Manually add -mignore-start-align option without partial
linking.
Gcc -falign-functions add .align 5 to the start of a section, it causes some
error message mismatch. Set these testcases to xfail on LoongArch target.
Diff:
---
gas/config/tc-loongarch.c | 70 +++++++++++++++-------
...ax-align-first.d => relax-align-ignore-start.d} | 2 +-
...ax-align-first.s => relax-align-ignore-start.s} | 0
include/opcode/loongarch.h | 1 +
ld/testsuite/ld-elf/dwarf.exp | 5 ++
.../ld-loongarch-elf/partial-link-align-a.s | 2 +
.../ld-loongarch-elf/partial-link-align-b.s | 3 +
...ax-align-first.d => relax-align-ignore-start.d} | 1 +
...ax-align-first.s => relax-align-ignore-start.s} | 0
ld/testsuite/ld-loongarch-elf/relax.exp | 32 +++++++++-
ld/testsuite/ld-undefined/undefined.exp | 2 +
11 files changed, 95 insertions(+), 23 deletions(-)
diff --git a/gas/config/tc-loongarch.c b/gas/config/tc-loongarch.c
index d156477d1e6..00b8c80c3de 100644
--- a/gas/config/tc-loongarch.c
+++ b/gas/config/tc-loongarch.c
@@ -139,15 +139,17 @@ enum options
OPTION_ABI,
OPTION_FLOAT_ABI,
-
OPTION_FLOAT_ISA,
OPTION_LA_LOCAL_WITH_ABS,
OPTION_LA_GLOBAL_WITH_PCREL,
OPTION_LA_GLOBAL_WITH_ABS,
+
OPTION_RELAX,
OPTION_NO_RELAX,
+
OPTION_THIN_ADD_SUB,
+ OPTION_IGNORE_START_ALIGN,
OPTION_END_OF_ENUM,
};
@@ -165,6 +167,7 @@ struct option md_longopts[] =
{ "mrelax", no_argument, NULL, OPTION_RELAX },
{ "mno-relax", no_argument, NULL, OPTION_NO_RELAX },
{ "mthin-add-sub", no_argument, NULL, OPTION_THIN_ADD_SUB},
+ { "mignore-start-align", no_argument, NULL, OPTION_IGNORE_START_ALIGN},
{ NULL, no_argument, NULL, 0 }
};
@@ -247,6 +250,10 @@ md_parse_option (int c, const char *arg)
LARCH_opts.thin_add_sub = 1;
break;
+ case OPTION_IGNORE_START_ALIGN:
+ LARCH_opts.ignore_start_align = 1;
+ break;
+
case OPTION_IGNORE:
break;
@@ -1772,7 +1779,9 @@ md_show_usage (FILE *stream)
-mthin-add-sub Convert a pair of R_LARCH_ADD32/64 and R_LARCH_SUB32/64 to\n\
R_LARCH_32/64_PCREL as much as possible\n\
The option does not affect the generation of R_LARCH_32_PCREL\n\
- relocations in .eh_frame\n"));
+ relocations in .eh_frame\n\
+ -mignore-start-align Ignore .align if it is at the start of a section. This option\n\
+ can't be used when partial linking (ld -r).\n"));
}
static void
@@ -1794,39 +1803,60 @@ bool
loongarch_frag_align_code (int n, int max)
{
char *nops;
+ expressionS ex;
symbolS *s = NULL;
- bfd_vma insn_alignment = 4;
- bfd_vma bytes = (bfd_vma) 1 << n;
- bfd_vma worst_case_bytes = bytes - insn_alignment;
+ /* When not relaxing, loongarch_handle_align handles code alignment. */
+ if (!LARCH_opts.relax)
+ return false;
+
+ bfd_vma align_bytes = (bfd_vma) 1 << n;
+ bfd_vma worst_case_bytes = align_bytes - 4;
+ bfd_vma addend = worst_case_bytes;
+ bool align_max = max > 0 && (bfd_vma) max < worst_case_bytes;
/* If we are moving to a smaller alignment than the instruction size, then no
alignment is required. */
- if (bytes <= insn_alignment)
+ if (align_bytes <= 4)
return true;
- /* When not relaxing, loongarch_handle_align handles code alignment. */
- if (!LARCH_opts.relax)
- return false;
-
/* If max <= 0, ignore max.
If max >= worst_case_bytes, max has no effect.
Similar to gas/write.c relax_segment function rs_align_code case:
if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype). */
- if (max > 0 && (bfd_vma) max < worst_case_bytes)
+ if (align_max)
{
s = symbol_find (now_seg->name);
- worst_case_bytes = ALIGN_MAX_ADDEND (n, max);
+ addend = ALIGN_MAX_ADDEND (n, max);
+ }
+
+ if (LARCH_opts.ignore_start_align)
+ {
+ frag_grow (worst_case_bytes);
+ /* Use relaxable frag for .align.
+ If .align at the start of section, do nothing. Section alignment can
+ ensure correct alignment.
+ If .align is not at the start of a section, reserve NOP instructions
+ and R_LARCH_ALIGN relocation. */
+ nops = frag_var (rs_machine_dependent, worst_case_bytes, worst_case_bytes,
+ rs_align_code, s, addend, NULL);
}
+ else
+ {
+ nops = frag_more (worst_case_bytes);
+ if (align_max)
+ {
+ ex.X_add_symbol = s;
+ ex.X_op = O_symbol;
+ }
+ else
+ ex.X_op = O_constant;
+
+ ex.X_add_number = addend;
- frag_grow (worst_case_bytes);
- /* Use relaxable frag for .align.
- If .align at the start of section, do nothing. Section alignment can
- ensure correct alignment.
- If .align is not at the start of a section, reserve NOP instructions
- and R_LARCH_ALIGN relocation. */
- nops = frag_var (rs_machine_dependent, worst_case_bytes, worst_case_bytes,
- rs_align_code, s, worst_case_bytes, NULL);
+ fix_new_exp (frag_now, nops - frag_now->fr_literal, 0,
+ &ex, false, BFD_RELOC_LARCH_ALIGN);
+ }
/* Default write NOP for aligned bytes. */
loongarch_make_nops (nops, worst_case_bytes);
diff --git a/gas/testsuite/gas/loongarch/relax-align-first.d b/gas/testsuite/gas/loongarch/relax-align-ignore-start.d
similarity index 87%
rename from gas/testsuite/gas/loongarch/relax-align-first.d
rename to gas/testsuite/gas/loongarch/relax-align-ignore-start.d
index ec0698b6995..0a67392d163 100644
--- a/gas/testsuite/gas/loongarch/relax-align-first.d
+++ b/gas/testsuite/gas/loongarch/relax-align-ignore-start.d
@@ -1,4 +1,4 @@
-#as:
+#as: -mignore-start-align
#objdump: -dr
.*:[ ]+file format .*
diff --git a/gas/testsuite/gas/loongarch/relax-align-first.s b/gas/testsuite/gas/loongarch/relax-align-ignore-start.s
similarity index 100%
rename from gas/testsuite/gas/loongarch/relax-align-first.s
rename to gas/testsuite/gas/loongarch/relax-align-ignore-start.s
diff --git a/include/opcode/loongarch.h b/include/opcode/loongarch.h
index 251daf13943..965a164307f 100644
--- a/include/opcode/loongarch.h
+++ b/include/opcode/loongarch.h
@@ -256,6 +256,7 @@ dec2 : [1-9][0-9]?
int relax;
int thin_add_sub;
+ int ignore_start_align;
} LARCH_opts;
extern size_t loongarch_insn_length (insn_t insn);
diff --git a/ld/testsuite/ld-elf/dwarf.exp b/ld/testsuite/ld-elf/dwarf.exp
index 6a63269562c..a4748a47c98 100644
--- a/ld/testsuite/ld-elf/dwarf.exp
+++ b/ld/testsuite/ld-elf/dwarf.exp
@@ -52,6 +52,9 @@ set build_tests {
{"DWARF parse during linker error"
"" "-fno-toplevel-reorder"
{dwarf2a.c dwarf2b.c} {{error_output "dwarf2.err"}} "dwarf2.x"}
+}
+
+set build_tests_dwarf3 {
{"Handle no DWARF information"
"" "-g0"
{dwarf3.c} {{error_output "dwarf3.err"}} "dwarf3.x"}
@@ -72,6 +75,8 @@ set run_tests {
set old_CFLAGS "$CFLAGS_FOR_TARGET"
append CFLAGS_FOR_TARGET " $NOSANITIZE_CFLAGS"
run_cc_link_tests $build_tests
+setup_xfail loongarch*-*-*
+run_cc_link_tests $build_tests_dwarf3
run_ld_link_exec_tests $run_tests
set CFLAGS_FOR_TARGET "$old_CFLAGS"
diff --git a/ld/testsuite/ld-loongarch-elf/partial-link-align-a.s b/ld/testsuite/ld-loongarch-elf/partial-link-align-a.s
new file mode 100644
index 00000000000..a8b4f295ea7
--- /dev/null
+++ b/ld/testsuite/ld-loongarch-elf/partial-link-align-a.s
@@ -0,0 +1,2 @@
+.text
+la.local $t0, .text
diff --git a/ld/testsuite/ld-loongarch-elf/partial-link-align-b.s b/ld/testsuite/ld-loongarch-elf/partial-link-align-b.s
new file mode 100644
index 00000000000..46fa058b437
--- /dev/null
+++ b/ld/testsuite/ld-loongarch-elf/partial-link-align-b.s
@@ -0,0 +1,3 @@
+.text
+.align 4
+ret
diff --git a/ld/testsuite/ld-loongarch-elf/relax-align-first.d b/ld/testsuite/ld-loongarch-elf/relax-align-ignore-start.d
similarity index 92%
rename from ld/testsuite/ld-loongarch-elf/relax-align-first.d
rename to ld/testsuite/ld-loongarch-elf/relax-align-ignore-start.d
index 9a4fad8ea46..939cf427b4b 100644
--- a/ld/testsuite/ld-loongarch-elf/relax-align-first.d
+++ b/ld/testsuite/ld-loongarch-elf/relax-align-ignore-start.d
@@ -1,3 +1,4 @@
+#as: -mignore-start-align
#ld: -e0
#objdump: -d
diff --git a/ld/testsuite/ld-loongarch-elf/relax-align-first.s b/ld/testsuite/ld-loongarch-elf/relax-align-ignore-start.s
similarity index 100%
rename from ld/testsuite/ld-loongarch-elf/relax-align-first.s
rename to ld/testsuite/ld-loongarch-elf/relax-align-ignore-start.s
diff --git a/ld/testsuite/ld-loongarch-elf/relax.exp b/ld/testsuite/ld-loongarch-elf/relax.exp
index 23452142cd2..890f139d428 100644
--- a/ld/testsuite/ld-loongarch-elf/relax.exp
+++ b/ld/testsuite/ld-loongarch-elf/relax.exp
@@ -19,10 +19,38 @@
# MA 02110-1301, USA.
#
-if [istarget loongarch64-*-*] {
- run_dump_test "relax-align-first"
+proc run_partial_linking_align_test {} {
+ global as
+ global ld
+ global srcdir
+ global subdir
+ global runtests
+
+ set testname "partial-link-align"
+ if ![runtest_file_p $runtests $testname] then {
+ return
+ }
+ if { ![ld_assemble $as "$srcdir/$subdir/$testname-a.s" tmpdir/a.o]
+ || ![ld_assemble $as "$srcdir/$subdir/$testname-b.s" tmpdir/b.o]
+ || ![ld_link $ld tmpdir/$testname.os "tmpdir/a.o tmpdir/b.o -r"]
+ || ![ld_link $ld tmpdir/$testname "tmpdir/$testname.os -e0 -Ttext 0x1000"] } {
+ fail $testname
+ } else {
+ set objdump_output [run_host_cmd "objdump" "-d tmpdir/$testname"]
+ if { [ regexp ".*1010:\\s*4c000020\\s*jirl.*" $objdump_output ] } {
+ pass $testname
+ } else {
+ fail $testname
+ }
+ }
+}
+
+if [istarget loongarch64-*-*] {
if [isbuild loongarch64-*-*] {
+ run_dump_test "relax-align-ignore-start"
+ run_partial_linking_align_test
+
set testname "loongarch relax .exe build"
set pre_builds [list \
[list \
diff --git a/ld/testsuite/ld-undefined/undefined.exp b/ld/testsuite/ld-undefined/undefined.exp
index 6f7ea003c96..2cc67fef16e 100644
--- a/ld/testsuite/ld-undefined/undefined.exp
+++ b/ld/testsuite/ld-undefined/undefined.exp
@@ -74,6 +74,7 @@ if { ![check_compiler_available] } {
# in a literal pool outside the function, so that both the
# "undefined function" and "undefined line" tests fail.
setup_xfail xtensa*-*-linux*
+ setup_xfail loongarch*-*-*
set mf "tmpdir/undefined.o* in function `function':"
checkund $mf $testfn
@@ -154,6 +155,7 @@ if { ![check_compiler_available] } {
# eBPF doesn't support dwarf yet.
setup_xfail bpf-*-*
+ setup_xfail loongarch*-*-*
checkund $ml $testline
}
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