diff mbox series

i386: Support ISAs enabled at command-line with target attribute

Message ID 20190228182813.20992-1-hjl.tools@gmail.com
State New
Headers show
Series i386: Support ISAs enabled at command-line with target attribute | expand

Commit Message

H.J. Lu Feb. 28, 2019, 6:28 p.m. UTC 
__attribute__ ((target("arch=broadwell"))) should enable AVX with -mavx
at command-line.  When we apply target attribute, we need to clear
x_ix86_isa_flags_explicit and x_ix86_isa_flags2_explicit, which are
turned on at command-line, so that target features will be enabled.

mv17.C has a version for Haswell.  On machines with Haswell ISAs, when
GCC is configured with --with-arch=native, all versions will be compiled
with Haswell ISAs.  Compile mv17.C with -march=x86-64 to force that only
Haswell version is compiled with -march=haswell.

gcc/

	PR target/89456
	* config/i386/i386.c (ix86_valid_target_attribute_tree): Allow
	enabling ISAs which have been enabled at command-line.

gcc/testsuite/

	PR target/89456
	* g++.target/i386/mv17.C: Add -march=x86-64.
	* gcc.target/i386/pr89456-1.c: New test.
---
 gcc/config/i386/i386.c                    | 6 ++++++
 gcc/testsuite/g++.target/i386/mv17.C      | 2 +-
 gcc/testsuite/gcc.target/i386/pr89456-1.c | 9 +++++++++
 3 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.target/i386/pr89456-1.c
diff mbox series

Patch

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index c8f9957163b..2b72ca8359f 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -5539,6 +5539,12 @@  ix86_valid_target_attribute_tree (tree args,
     = TREE_TARGET_OPTION (target_option_default_node);
   struct gcc_options enum_opts_set;
 
+  /* Allow enabling ISAs which have been enabled at command-line so
+     that __attribute__ ((target("arch=broadwell"))) enables AVX when
+     there is -mavx at command-line.  */
+  opts->x_ix86_isa_flags_explicit &= ~ix86_isa_flags;
+  opts->x_ix86_isa_flags2_explicit &= ~ix86_isa_flags2;
+
   memset (&enum_opts_set, 0, sizeof (enum_opts_set));
 
   /* Process each of the options on the chain.  */
diff --git a/gcc/testsuite/g++.target/i386/mv17.C b/gcc/testsuite/g++.target/i386/mv17.C
index fefbfaac6ff..17d125227d7 100644
--- a/gcc/testsuite/g++.target/i386/mv17.C
+++ b/gcc/testsuite/g++.target/i386/mv17.C
@@ -2,7 +2,7 @@ 
 
 // { dg-do run }
 // { dg-require-ifunc "" }
-// { dg-options "-O2" }
+// { dg-options "-O2 -march=x86-64" }
 
 #include <assert.h>
 
diff --git a/gcc/testsuite/gcc.target/i386/pr89456-1.c b/gcc/testsuite/gcc.target/i386/pr89456-1.c
new file mode 100644
index 00000000000..87a3a820898
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr89456-1.c
@@ -0,0 +1,9 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -mavx -march=x86-64" } */
+
+__attribute__ ((target("arch=broadwell")))
+float
+foo (float x)
+{
+  return x;
+}