Hi!
The GENERIC folding of these builtins have cases where it folds to a
constant regardless of the value of the first operand. If so, we need
to use omit_one_operand to avoid throwing away side-effects in the first
operand if any. The cases which verify the first argument is INTEGER_CST
don't need that, INTEGER_CST doesn't have side-effects.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2024-08-09 Jakub Jelinek <ja...@redhat.com>
PR target/116287
* config/i386/i386.cc (ix86_fold_builtin) <case IX86_BUILTIN_BEXTR32>:
When folding into zero without checking whether first argument is
constant, use omit_one_operand.
(ix86_fold_builtin) <case IX86_BUILTIN_BZHI32>: Likewise.
* gcc.target/i386/bmi-pr116287.c: New test.
* gcc.target/i386/bmi2-pr116287.c: New test.
* gcc.target/i386/tbm-pr116287.c: New test.
--- gcc/config/i386/i386.cc.jj 2024-08-01 14:33:28.172801480 +0200
+++ gcc/config/i386/i386.cc 2024-08-08 12:55:12.780696418 +0200
@@ -18549,9 +18549,11 @@ ix86_fold_builtin (tree fndecl, int n_ar
unsigned int prec = TYPE_PRECISION (TREE_TYPE (args[0]));
unsigned int start = tree_to_uhwi (args[1]);
unsigned int len = (start & 0xff00) >> 8;
+ tree lhs_type = TREE_TYPE (TREE_TYPE (fndecl));
start &= 0xff;
if (start >= prec || len == 0)
- res = 0;
+ return omit_one_operand (lhs_type, build_zero_cst (lhs_type),
+ args[0]);
else if (!tree_fits_uhwi_p (args[0]))
break;
else
@@ -18560,7 +18562,7 @@ ix86_fold_builtin (tree fndecl, int n_ar
len = prec;
if (len < HOST_BITS_PER_WIDE_INT)
res &= (HOST_WIDE_INT_1U << len) - 1;
- return build_int_cstu (TREE_TYPE (TREE_TYPE (fndecl)), res);
+ return build_int_cstu (lhs_type, res);
}
break;
@@ -18570,15 +18572,17 @@ ix86_fold_builtin (tree fndecl, int n_ar
if (tree_fits_uhwi_p (args[1]))
{
unsigned int idx = tree_to_uhwi (args[1]) & 0xff;
+ tree lhs_type = TREE_TYPE (TREE_TYPE (fndecl));
if (idx >= TYPE_PRECISION (TREE_TYPE (args[0])))
return args[0];
if (idx == 0)
- return build_int_cst (TREE_TYPE (TREE_TYPE (fndecl)), 0);
+ return omit_one_operand (lhs_type, build_zero_cst (lhs_type),
+ args[0]);
if (!tree_fits_uhwi_p (args[0]))
break;
unsigned HOST_WIDE_INT res = tree_to_uhwi (args[0]);
res &= ~(HOST_WIDE_INT_M1U << idx);
- return build_int_cstu (TREE_TYPE (TREE_TYPE (fndecl)), res);
+ return build_int_cstu (lhs_type, res);
}
break;
--- gcc/testsuite/gcc.target/i386/bmi-pr116287.c.jj 2024-08-08
13:14:25.566827913 +0200
+++ gcc/testsuite/gcc.target/i386/bmi-pr116287.c 2024-08-08
13:21:32.718312216 +0200
@@ -0,0 +1,28 @@
+/* PR target/116287 */
+/* { dg-do run { target bmi } } */
+/* { dg-options "-O2 -mbmi" } */
+
+#include <x86intrin.h>
+
+#include "bmi-check.h"
+
+static void
+bmi_test ()
+{
+ unsigned int a = 0;
+ if (__builtin_ia32_bextr_u32 (a++, 0) != 0)
+ abort ();
+ if (__builtin_ia32_bextr_u32 (a++, 0x120) != 0)
+ abort ();
+ if (a != 2)
+ abort ();
+#ifdef __x86_64__
+ unsigned long long b = 0;
+ if (__builtin_ia32_bextr_u64 (b++, 0) != 0)
+ abort ();
+ if (__builtin_ia32_bextr_u64 (b++, 0x140) != 0)
+ abort ();
+ if (b != 2)
+ abort ();
+#endif
+}
--- gcc/testsuite/gcc.target/i386/bmi2-pr116287.c.jj 2024-08-08
13:22:55.263246127 +0200
+++ gcc/testsuite/gcc.target/i386/bmi2-pr116287.c 2024-08-08
13:30:44.851181267 +0200
@@ -0,0 +1,24 @@
+/* PR target/116287 */
+/* { dg-do run { target bmi2 } } */
+/* { dg-options "-O2 -mbmi2" } */
+
+#include <x86intrin.h>
+
+#include "bmi2-check.h"
+
+static void
+bmi2_test ()
+{
+ unsigned int a = 0;
+ if (__builtin_ia32_bzhi_si (a++, 0) != 0)
+ abort ();
+ if (a != 1)
+ abort ();
+#ifdef __x86_64__
+ unsigned long long b = 0;
+ if (__builtin_ia32_bzhi_di (b++, 0) != 0)
+ abort ();
+ if (b != 1)
+ abort ();
+#endif
+}
--- gcc/testsuite/gcc.target/i386/tbm-pr116287.c.jj 2024-08-08
13:14:48.453532722 +0200
+++ gcc/testsuite/gcc.target/i386/tbm-pr116287.c 2024-08-08
13:22:36.940482770 +0200
@@ -0,0 +1,29 @@
+/* PR target/116287 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -mtbm -fdump-tree-optimized" } */
+/* { dg-final { scan-tree-dump-not "link_error \\\(\\\);" "optimized" } } */
+
+#include <x86intrin.h>
+
+extern void link_error (void);
+
+void
+tbm_test ()
+{
+ unsigned int a = 0;
+ if (__builtin_ia32_bextri_u32 (a++, 0) != 0)
+ link_error ();
+ if (__builtin_ia32_bextri_u32 (a++, 0x120) != 0)
+ link_error ();
+ if (a != 2)
+ link_error ();
+#ifdef __x86_64__
+ unsigned long long b = 0;
+ if (__builtin_ia32_bextr_u64 (b++, 0) != 0)
+ link_error ();
+ if (__builtin_ia32_bextr_u64 (b++, 0x140) != 0)
+ link_error ();
+ if (b != 2)
+ link_error ();
+#endif
+}
Jakub
