Hello! As mentioned in the PR [1], comment #9, the fix for the ICE is not optimal (if not wrong). The problem with mem/mem operands was fixed as a fixup in the expander, where operands[1] was pulled into a register. Unfortunately, unaligned moves should not be handled in the same way as aligned moves, since one of the operands is unaligned. As it turns out, for the testcase form the PR, the expander pulls the wrong operand:
--cut here-- /* { dg-do compile } */ /* { dg-options "-msse2 -ffloat-store" } */ typedef double v2df __attribute__((vector_size (16))); v2df foo (double *d) { return __builtin_ia32_loadupd (d); } --cut here-- movsd (%rax), %xmm0 movhpd 8(%rax), %xmm0 movupd %xmm0, -16(%rbp) movapd -16(%rbp), %xmm0 So, we move (unaligned!) memory to a register, and then use movupd to store to aligned stack slot. Luckily, gcc figures that the load is from unaligned memory and generates movsd/movhpd combo. The intention was to generate: movupd (%rax), %xmm0 movapd %xmm0, -16(%rbp) movapd -16(%rbp), %xmm0 So, we don't want a fixup in the expander, but we should always load to a register for the "load" builtin class. 2012-05-14 Uros Bizjak <ubiz...@gmail.com> PR target/46098 * config/i386/i386.c (ix86_expand_special_args_builtin): Always generate target register for "load" class builtins. Revert: 2010-10-22 Uros Bizjak <ubiz...@gmail.com> PR target/46098 * config/i386/sse.md (*avx_movu<ssemodesuffix><avxmodesuffix>): Rename from avx_movu<ssemodesuffix><avxmodesuffix>. (avx_movu<ssemodesuffix><avxmodesuffix>): New expander. (*<sse>_movu<ssemodesuffix>): Rename from <sse>_movu<ssemodesuffix>. (<sse>_movu<ssemodesuffix>): New expander. (*avx_movdqu<avxmodesuffix>): Rename from avx_movdqu<avxmodesuffix>. (avx_movdqu<avxmodesuffix>): New expander. (*sse2_movdqu): Rename from sse2_movdqu. (sse2_movdqu): New expander. testsuite/ChangeLog: 2012-05-14 Uros Bizjak <ubiz...@gmail.com> * gcc.target/i386/avx256-unaligned-load-[1234].c: Update scan strings. * gcc.target/i386/avx256-unaligned-store-[1234].c: Ditto. Attached patch was bootstrapped and regression tested on x86_64-pc-linux-gnu {,-m32}. Patch will be committed to SVN and all release branches. [1] http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46098 Uros.
Index: config/i386/i386.c =================================================================== --- config/i386/i386.c (revision 187465) +++ config/i386/i386.c (working copy) @@ -29472,8 +29472,8 @@ ix86_expand_special_args_builtin (const struct bui arg_adjust = 0; if (optimize || target == 0 - || GET_MODE (target) != tmode - || !insn_p->operand[0].predicate (target, tmode)) + || !register_operand (target, tmode) + || GET_MODE (target) != tmode) target = gen_reg_rtx (tmode); } Index: config/i386/sse.md =================================================================== --- config/i386/sse.md (revision 187465) +++ config/i386/sse.md (working copy) @@ -588,18 +588,7 @@ DONE; }) -(define_expand "<sse>_movu<ssemodesuffix><avxsizesuffix>" - [(set (match_operand:VF 0 "nonimmediate_operand") - (unspec:VF - [(match_operand:VF 1 "nonimmediate_operand")] - UNSPEC_MOVU))] - "TARGET_SSE" -{ - if (MEM_P (operands[0]) && MEM_P (operands[1])) - operands[1] = force_reg (<MODE>mode, operands[1]); -}) - -(define_insn "*<sse>_movu<ssemodesuffix><avxsizesuffix>" +(define_insn "<sse>_movu<ssemodesuffix><avxsizesuffix>" [(set (match_operand:VF 0 "nonimmediate_operand" "=x,m") (unspec:VF [(match_operand:VF 1 "nonimmediate_operand" "xm,x")] @@ -631,17 +620,7 @@ ] (const_string "<MODE>")))]) -(define_expand "<sse2>_movdqu<avxsizesuffix>" - [(set (match_operand:VI1 0 "nonimmediate_operand") - (unspec:VI1 [(match_operand:VI1 1 "nonimmediate_operand")] - UNSPEC_MOVU))] - "TARGET_SSE2" -{ - if (MEM_P (operands[0]) && MEM_P (operands[1])) - operands[1] = force_reg (<MODE>mode, operands[1]); -}) - -(define_insn "*<sse2>_movdqu<avxsizesuffix>" +(define_insn "<sse2>_movdqu<avxsizesuffix>" [(set (match_operand:VI1 0 "nonimmediate_operand" "=x,m") (unspec:VI1 [(match_operand:VI1 1 "nonimmediate_operand" "xm,x")] UNSPEC_MOVU))] Index: testsuite/gcc.target/i386/avx256-unaligned-store-2.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-store-2.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-store-2.c (working copy) @@ -24,6 +24,6 @@ avx_test (void) } } -/* { dg-final { scan-assembler-not "\\*avx_movdqu256/2" } } */ +/* { dg-final { scan-assembler-not "avx_movdqu256/2" } } */ /* { dg-final { scan-assembler "vmovdqu.*\\*movv16qi_internal/3" } } */ /* { dg-final { scan-assembler "vextract.128" } } */ Index: testsuite/gcc.target/i386/avx256-unaligned-load-3.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-load-3.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-load-3.c (working copy) @@ -14,6 +14,6 @@ avx_test (void) c[i] = a[i] * b[i+3]; } -/* { dg-final { scan-assembler-not "\\*avx_movupd256/1" } } */ -/* { dg-final { scan-assembler "\\*sse2_movupd/1" } } */ +/* { dg-final { scan-assembler-not "avx_movupd256/1" } } */ +/* { dg-final { scan-assembler "sse2_movupd/1" } } */ /* { dg-final { scan-assembler "vinsertf128" } } */ Index: testsuite/gcc.target/i386/avx256-unaligned-store-3.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-store-3.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-store-3.c (working copy) @@ -17,6 +17,6 @@ avx_test (void) d[i] = c[i] * 20.0; } -/* { dg-final { scan-assembler-not "\\*avx_movupd256/2" } } */ +/* { dg-final { scan-assembler-not "avx_movupd256/2" } } */ /* { dg-final { scan-assembler "vmovupd.*\\*movv2df_internal/3" } } */ /* { dg-final { scan-assembler "vextractf128" } } */ Index: testsuite/gcc.target/i386/avx256-unaligned-load-4.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-load-4.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-load-4.c (working copy) @@ -14,6 +14,6 @@ avx_test (void) b[i] = a[i+3] * 2; } -/* { dg-final { scan-assembler "\\*avx_movups256/1" } } */ -/* { dg-final { scan-assembler-not "\\*avx_movups/1" } } */ +/* { dg-final { scan-assembler "avx_movups256/1" } } */ +/* { dg-final { scan-assembler-not "avx_movups/1" } } */ /* { dg-final { scan-assembler-not "vinsertf128" } } */ Index: testsuite/gcc.target/i386/avx256-unaligned-store-4.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-store-4.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-store-4.c (working copy) @@ -14,7 +14,7 @@ avx_test (void) b[i+3] = a[i] * c[i]; } -/* { dg-final { scan-assembler "\\*avx_movups256/2" } } */ -/* { dg-final { scan-assembler-not "\\*avx_movups/2" } } */ +/* { dg-final { scan-assembler "avx_movups256/2" } } */ +/* { dg-final { scan-assembler-not "avx_movups/2" } } */ /* { dg-final { scan-assembler-not "\\*avx_movv4sf_internal/3" } } */ /* { dg-final { scan-assembler-not "vextractf128" } } */ Index: testsuite/gcc.target/i386/avx256-unaligned-load-1.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-load-1.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-load-1.c (working copy) @@ -14,6 +14,6 @@ avx_test (void) c[i] = a[i] * b[i+3]; } -/* { dg-final { scan-assembler-not "\\*avx_movups256/1" } } */ -/* { dg-final { scan-assembler "\\*sse_movups/1" } } */ +/* { dg-final { scan-assembler-not "avx_movups256/1" } } */ +/* { dg-final { scan-assembler "sse_movups/1" } } */ /* { dg-final { scan-assembler "vinsertf128" } } */ Index: testsuite/gcc.target/i386/avx256-unaligned-store-1.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-store-1.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-store-1.c (working copy) @@ -17,6 +17,6 @@ avx_test (void) d[i] = c[i] * 20.0; } -/* { dg-final { scan-assembler-not "\\*avx_movups256/2" } } */ +/* { dg-final { scan-assembler-not "avx_movups256/2" } } */ /* { dg-final { scan-assembler "vmovups.*\\*movv4sf_internal/3" } } */ /* { dg-final { scan-assembler "vextractf128" } } */ Index: testsuite/gcc.target/i386/avx256-unaligned-load-2.c =================================================================== --- testsuite/gcc.target/i386/avx256-unaligned-load-2.c (revision 187465) +++ testsuite/gcc.target/i386/avx256-unaligned-load-2.c (working copy) @@ -24,6 +24,6 @@ avx_test (void) } } -/* { dg-final { scan-assembler-not "\\*avx_movdqu256/1" } } */ -/* { dg-final { scan-assembler "\\*sse2_movdqu/1" } } */ +/* { dg-final { scan-assembler-not "avx_movdqu256/1" } } */ +/* { dg-final { scan-assembler "sse2_movdqu/1" } } */ /* { dg-final { scan-assembler "vinsert.128" } } */