Now that TARGET_MMX_WITH_SSE is implemented, the compiler should be
able to auto-vectorize:
void
foo (char *restrict r, char *restrict a)
{
for (int i = 0; i < 8; i++)
r[i] += a[i];
}
Attached patch enables the conversion and produces:
foo:
movq (%rdi), %xmm1
movq (%rsi), %xmm0
paddb %xmm1, %xmm0
movq %xmm0, (%rdi)
ret
Please note that the patch regresses
FAIL: gcc.target/i386/sse2-vect-simd-11.c scan-tree-dump-times vect
"vectorized [1-3] loops" 2
FAIL: gcc.target/i386/sse2-vect-simd-15.c scan-tree-dump-times vect
"vectorized [1-3] loops" 2
For some reason, the compiler decides to vectorize with 8-byte
vectors, resulting in:
missed: not vectorized: relevant stmt not supported: _8 = (short
unsigned int) _4;
missed: bad operation or unsupported loop bound.
missed: couldn't vectorize loop
However, the unpatched compiler is able to vectorize loop using
16-byte vectors. It looks that the compiler should re-run
vectorization with wider vectors, if vectorization with narrower
vectors fails. Jakub, Richard, do you have any insight in this issue?
2019-06-26 Uroš Bizjak <ubiz...@gmail.com>
* config/i386/i386.c (ix86_autovectorize_vector_sizes):
Autovectorize 8-byte vectors for TARGET_MMX_WITH_SSE.
testsuite/ChangeLog:
2019-06-26 Uroš Bizjak <ubiz...@gmail.com>
* lib/target-supports.exp (available_vector_sizes)
<[istarget i?86-*-*] || [istarget x86_64-*-*]>: Add
64-bit vectors for !ia32.
The patch was bootstrapped and regression tested on x86_64-linux-gnu {,-m32}.
Uros.
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 1ca1712183dc..24bd0896f137 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -21401,6 +21401,9 @@ ix86_autovectorize_vector_sizes (vector_sizes *sizes,
bool all)
sizes->safe_push (16);
sizes->safe_push (32);
}
+
+ if (TARGET_MMX_WITH_SSE)
+ sizes->safe_push (8);
}
/* Implemenation of targetm.vectorize.get_mask_mode. */
diff --git a/gcc/testsuite/lib/target-supports.exp
b/gcc/testsuite/lib/target-supports.exp
index 1d4aaa2a87ec..285c32f8cebb 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -6603,9 +6603,14 @@ proc available_vector_sizes { } {
} elseif { [istarget arm*-*-*]
&& [check_effective_target_arm_neon_ok] } {
lappend result 128 64
- } elseif { (([istarget i?86-*-*] || [istarget x86_64-*-*])
- && ([check_avx_available] && ![check_prefer_avx128])) } {
- lappend result 256 128
+ } elseif { [istarget i?86-*-*] || [istarget x86_64-*-*] } {
+ if { [check_avx_available] && ![check_prefer_avx128] } {
+ lappend result 256
+ }
+ lappend result 128
+ if { ![is-effective-target ia32] } {
+ lappend result 64
+ }
} elseif { [istarget sparc*-*-*] } {
lappend result 64
} else {
