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| author | Segher Boessenkool <segher@kernel.crashing.org> | 2019-03-19 17:58:42 +0100 |
|---|---|---|
| committer | Segher Boessenkool <segher@gcc.gnu.org> | 2019-03-19 17:58:42 +0100 |
| commit | e8926ce09f3ef0795b87dc922f431157e6916748 (patch) | |
| tree | 27529516a80a71b94af1fe3a2dfaa158936fc923 /gcc | |
| parent | bb48c402f4ca67c9e5d0ed1104700c50058d6fb8 (diff) | |
| download | gcc-e8926ce09f3ef0795b87dc922f431157e6916748.zip gcc-e8926ce09f3ef0795b87dc922f431157e6916748.tar.gz gcc-e8926ce09f3ef0795b87dc922f431157e6916748.tar.bz2 | |
rs6000: Unaligned stfiwx on older CPUs (PR89746)
The "classic" PowerPCs (6xx/7xx) are not STRICT_ALIGNMENT, but their
floating point units are. This is not normally a problem, the ABIs
make everything FP aligned. The RTL patterns converting FP to integer
however get a potentially unaligned destination, and we do not want to
do an stfiwx on that on such older CPUs.
This fixes it. It does not change anything for TARGET_MFCRF targets
(POWER4 and later). It also won't change anything for strict-alignment
targets, or CPUs without hardware FP of course, or CPUs that do not
implement stfiwx (older 4xx/5xx/8xx).
It does not change the corresponding fixuns* pattern, because that can
not be enabled on any CPU that cannot handle unaligned FP well.
PR target/89746
* config/rs6000/rs6000.md (fix_trunc<mode>si2_stfiwx): If we have a
non-TARGET_MFCRF target, and the dest is memory but not 32-bit aligned,
go via a stack temporary.
From-SVN: r269802
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/config/rs6000/rs6000.md | 4 |
2 files changed, 9 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index f2ce11d..510faab8 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2018-03-19 Segher Boessenkool <segher@kernel.crashing.org> + + PR target/89746 + * config/rs6000/rs6000.md (fix_trunc<mode>si2_stfiwx): If we have a + non-TARGET_MFCRF target, and the dest is memory but not 32-bit aligned, + go via a stack temporary. + 2019-03-19 Jakub Jelinek <jakub@redhat.com> PR target/89378 diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md index 584b9da..297b884 100644 --- a/gcc/config/rs6000/rs6000.md +++ b/gcc/config/rs6000/rs6000.md @@ -5639,13 +5639,13 @@ tmp = gen_reg_rtx (DImode); emit_insn (gen_fctiwz_<mode> (tmp, src)); - if (MEM_P (dest)) + if (MEM_P (dest) && (TARGET_MFCRF || MEM_ALIGN (dest) >= 32)) { dest = rs6000_force_indexed_or_indirect_mem (dest); emit_insn (gen_stfiwx (dest, tmp)); DONE; } - else if (TARGET_POWERPC64 && (TARGET_MFPGPR || TARGET_DIRECT_MOVE)) + else if (TARGET_POWERPC64 && (TARGET_MFPGPR || TARGET_DIRECT_MOVE) && !MEM_P (dest)) { dest = gen_lowpart (DImode, dest); emit_move_insn (dest, tmp); |