https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91758
Martin Liška <marxin at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #5 from Martin Liška <marxin at gcc dot gnu.org> ---
Ok, so without changed source file I see optimized dump changed from:
D.1259546.PaddingInReg = SR.6329_147;
D.1259546.IndirectByVal = SR.6330_121;
D.1259546.IndirectRealign = SR.6331_117;
D.1259546.SRetAfterThis = SR.6332_29;
D.1259546.InReg = SR.6333_124;
D.1259546.CanBeFlattened = SR.6334_129;
MEM[base: __for_begin_145, offset: 8B] = MEM[(struct ABIArgInfo
*)&D.1259546];
into:
_139 = (unsigned char) SR.6329_147;
_49 = (unsigned char) SR.6330_121;
_137 = _49 << 2;
_34 = _137 | _139;
_382 = (unsigned char) SR.6331_117;
_381 = _382 << 3;
_357 = _381 | _34;
_380 = (unsigned char) SR.6332_29;
_377 = _380 << 4;
_376 = _377 | _357;
_375 = (unsigned char) SR.6333_124;
_397 = _375 << 5;
_401 = _397 | _376;
_181 = (unsigned char) SR.6334_129;
_364 = _181 << 6;
_118 = _364 | _401;
_131 = MEM[(struct ABIArgInfo *)&D.1259546 + 21B];
_363 = _131 & 130;
_366 = _118 & 125;
_69 = _363 | _366;
MEM[(struct ABIArgInfo *)&D.1259546 + 21B] = _69;
MEM[base: __for_begin_145, offset: 8B] = MEM[(struct ABIArgInfo
*)&D.1259546];
which eventually ends up with something like:
addq $32, %rbx #, ivtmp.6357
movzbl 43(%rsp), %ecx # %sfp, SR.6331
movq 24(%rsp), %xmm0 # %sfp, tmp336
movl %r15d, -8(%rbx) # SR.6327, MEM[base: __for_begin_145, offset:
8B]
leal 0(,%rdi,4), %edx #, tmp337
# /tmp/llvm-project/clang/lib/CodeGen/TargetInfo.cpp:7572:
__builtin_printf ("after: I.info: %d\n", I.info.getInReg ());
leaq .LC156(%rip), %rdi #,
# /tmp/llvm-project/clang/lib/CodeGen/TargetInfo.cpp:7571: I.info =
classifyArgumentType(I.type, State);
movl %r15d, 80(%rsp) # SR.6327, MEM[(struct ABIArgInfo *)&D.1259546
+ 16B]
sall $3, %ecx #, tmp339
orl %r14d, %edx # SR.6329, tmp338
movhps 8(%rsp), %xmm0 # %sfp, tmp336
orl %ecx, %edx # tmp339, tmp340
movzbl 42(%rsp), %ecx # %sfp, tmp341
movups %xmm0, -24(%rbx) # tmp336, MEM[base: __for_begin_145,
offset: 8B]
movaps %xmm0, 64(%rsp) # tmp336, MEM[(struct ABIArgInfo *)&D.1259546]
sall $4, %ecx #, tmp341
orl %ecx, %edx # tmp341, tmp342
orl %eax, %edx # tmp343, tmp344
movl %ebp, %eax # SR.6334, tmp345
sall $6, %eax #, tmp345
orl %eax, %edx # tmp345, tmp346
movzbl 85(%rsp), %eax # MEM[(struct ABIArgInfo *)&D.1259546 + 21B],
tmp348
andl $125, %edx #, tmp347
andl $-126, %eax #, tmp348
orl %eax, %edx # tmp348, tmp350
# /tmp/llvm-project/clang/lib/CodeGen/TargetInfo.cpp:7572:
__builtin_printf ("after: I.info: %d\n", I.info.getInReg ());
xorl %eax, %eax #
# /tmp/llvm-project/clang/lib/CodeGen/TargetInfo.cpp:7571: I.info =
classifyArgumentType(I.type, State);
movb %dl, 85(%rsp) # tmp350, MEM[(struct ABIArgInfo *)&D.1259546 +
21B]
and the problem is that we load:
0x2776490 <(anonymous
namespace)::LanaiABIInfo::computeInfo(clang::CodeGen::CGFunctionInfo&)
const+400> movzbl 0x2b(%rsp),%ecx
with the following value:
(gdb) p /t $ecx
$1 = 11110111
and then we or (11110111 << 3) into %edx and so that we end up with the 6th bit
set.
That is the InReg field.
Looking at the corresponding ASM code without the store-merging, there are
quite some
andl $1, %esi #, tmp329
...
andl $1, %ecx #, tmp347
and so on.
@Eric, @Jakub, @Richard: Aren't we missing something similar with the store
merging of bool:1 bit fields?
I can see the cast to 'unsigned char' from 'bool' in GIMPLE. Both should be 1B
and
so that we maybe encorporate random bits?
