Add -fno-math-errno to gcc.dg/lto/20110201-1_0.c
Richard Sandiford
richard.sandiford@arm.com
Fri Nov 6 14:34:00 GMT 2015
At the moment the ECF_* flags for a gimple call to a built-in
function are derived from the function decl, which in turn is
derived from the global command-line options. So if the compiler
is run with -fno-math-errno, we always assume functions don't set
errno, regardless of local optimization options. Similarly if the
compiler is run with -fmath-errno, we always assume functions set errno.
This shows up in gcc.dg/lto/20110201-1_0.c, where we compile
the file with -O0 and use -O2 -ffast-math for a specific function.
-O2 -ffast-math is enough for us to convert cabs to sqrt as hoped,
but because of the global -fmath-errno setting, we assume that the
call to sqrt is not pure or const and create vops for it. This makes
it appear to the gimple code that a simple sqrt optab isn't enough.
Later patches move more decisions about maths functions to gimple
and think that in this case we should use:
y = sqrt (x);
if (!(x >= 0))
sqrt (x); // to set errno.
This is being tracked as PR68235. For now the patch adds
-fno-math-errno to the dg-options for this test.
Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.
OK to install?
Thanks,
Richard
gcc/testsuite/
PR tree-optimization/68235
* gcc.dg/lto/20110201-1_0.c: Add -fno-math-errno.
diff --git a/gcc/testsuite/gcc.dg/lto/20110201-1_0.c b/gcc/testsuite/gcc.dg/lto/20110201-1_0.c
index 068dddc..2144f07 100644
--- a/gcc/testsuite/gcc.dg/lto/20110201-1_0.c
+++ b/gcc/testsuite/gcc.dg/lto/20110201-1_0.c
@@ -1,6 +1,6 @@
/* { dg-lto-do run } */
-/* { dg-lto-options { { -O0 -flto } } } */
-/* { dg-lto-options { "-O0 -flto -mfloat-abi=softfp -mfpu=neon-vfpv4" } { target arm*-*-* } } */
+/* { dg-lto-options { { -O0 -flto -fno-math-errno } } } */
+/* { dg-lto-options { "-O0 -flto -fno-math-errno -mfloat-abi=softfp -mfpu=neon-vfpv4" } { target arm*-*-* } } */
/* { dg-require-linker-plugin "" } */
/* { dg-require-effective-target sqrt_insn } */
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