This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
[PATCH] Fix -march=knl wrong-code (PR target/84786)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Uros Bizjak <ubizjak at gmail dot com>, Kirill Yukhin <kirill dot yukhin at gmail dot com>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Mon, 12 Mar 2018 21:52:07 +0100
- Subject: [PATCH] Fix -march=knl wrong-code (PR target/84786)
- Authentication-results: sourceware.org; auth=none
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
For TARGET_AVX512F && !TARGET_AVX512VL, the RA ensures that
128-bit and 256-bit vectors aren't allocated in %xmm16+ registers,
but not so for scalar modes. In that case we use avx512vl isa attribute,
or TARGET_AVX512VL guards, or Yv constraint.
The following patch does the last one for sse2_loadhpd pattern where the
last argument has DFmode and thus using v constraint for it is unsafe
and on the testcase we emit
vunpcklpd %xmm18, %xmm0, %xmm0
instruction which needs avx512vl. Bootstrapped/regtested on x86_64-linux
and i686-linux, ok for trunk?
2018-03-12 Jakub Jelinek <jakub@redhat.com>
PR target/84786
* config/i386/sse.md (sse2_loadhpd): Use Yv constraint rather than v
on the last operand.
* gcc.target/i386/avx512f-pr84786-1.c: New test.
* gcc.target/i386/avx512f-pr84786-2.c: New test.
--- gcc/config/i386/sse.md.jj 2018-03-05 17:00:24.568655800 +0100
+++ gcc/config/i386/sse.md 2018-03-12 11:05:48.917401886 +0100
@@ -9022,14 +9022,14 @@ (define_expand "sse2_loadhpd_exp"
;; see comment above inline_secondary_memory_needed function in i386.c
(define_insn "sse2_loadhpd"
[(set (match_operand:V2DF 0 "nonimmediate_operand"
- "=x,v,x,v,o,o ,o")
+ "=x,v,x,v ,o,o ,o")
(vec_concat:V2DF
(vec_select:DF
(match_operand:V2DF 1 "nonimmediate_operand"
- " 0,v,0,v,0,0 ,0")
+ " 0,v,0,v ,0,0 ,0")
(parallel [(const_int 0)]))
(match_operand:DF 2 "nonimmediate_operand"
- " m,m,x,v,x,*f,r")))]
+ " m,m,x,Yv,x,*f,r")))]
"TARGET_SSE2 && !(MEM_P (operands[1]) && MEM_P (operands[2]))"
"@
movhpd\t{%2, %0|%0, %2}
--- gcc/testsuite/gcc.target/i386/avx512f-pr84786-1.c.jj 2018-03-12 11:32:33.563665173 +0100
+++ gcc/testsuite/gcc.target/i386/avx512f-pr84786-1.c 2018-03-12 11:35:33.964695384 +0100
@@ -0,0 +1,25 @@
+/* PR target/84786 */
+/* { dg-do run { target { ! ia32 } } } */
+/* { dg-options "-mavx512f -mno-avx512vl -O2" } */
+/* { dg-require-effective-target avx512f } */
+
+#include "avx512f-check.h"
+
+typedef double V __attribute__((vector_size (16)));
+
+__attribute__((noipa)) V
+foo (V x, double y)
+{
+ register double z __asm ("xmm18");
+ asm volatile ("" : "=v" (z) : "0" (y));
+ x[1] = z;
+ return x;
+}
+
+static void
+avx512f_test (void)
+{
+ V a = foo ((V) { 1.0, 2.0 }, 3.0);
+ if (a[0] != 1.0 || a[1] != 3.0)
+ abort ();
+}
--- gcc/testsuite/gcc.target/i386/avx512f-pr84786-2.c.jj 2018-03-12 11:32:43.445666826 +0100
+++ gcc/testsuite/gcc.target/i386/avx512f-pr84786-2.c 2018-03-12 11:35:45.260697279 +0100
@@ -0,0 +1,16 @@
+/* PR target/84786 */
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-options "-mavx512f -mno-avx512vl -O2" } */
+
+typedef double V __attribute__((vector_size (16)));
+
+__attribute__((noipa)) V
+foo (V x, double y)
+{
+ register double z __asm ("xmm18");
+ asm volatile ("" : "=v" (z) : "0" (y));
+ x[1] = z;
+ return x;
+}
+
+/* { dg-final { scan-assembler-not "vunpcklpd\[\^\n\r]*xmm(1\[6-9]|\[23]\[0-9])" } } */
Jakub