Some of the parallel MIPS tests that I ran recently seemed to be
nondeterministic. Some tests were skipped and others were duplicated.
This turned out to be because some MIPS check_effective_target
procedures accept optional command-line flags. Sometimes the
procedures are called as normal, without flags, and sometimes
they are passed an explicit -m option.
The problem is that both invocations use the same cache identifier.
This means that the result of the first invocation (with or without
flags) is used for all subsequent invocations (with or without flags).
And the first invocation depends on which tests are being run by a
particular parallel thread.
As a result, the parallel threads did not agree on which tests
needed to be run, and so got out of sync.
The flags passed to the procedures all seem to be valid filenames,
so this patch simply adds the flags to the cache identifier.
It's a bit of a hack, and I'm not sure that this pattern should
be followed for future tests.
Doing that made check_effective_target_mpaired_single always succeed
when no flags were passed, since it simply tests an empty function.
Since there is no predefined macro (AFAICT), the patch tests for support
using the same asm as check_mpaired_single_hw_available (but with an
assemble test rather than with a run test).
Also, check_mpaired_single_hw_available did not pass -mpaired-single
to the hardware test, unlike the loongson_mmi and mma equivalents.
Tested on mips64-linux-gnu. Also tested by following Jakub's recipe
in the comments above gcc_parallel_test_run_p: the md5sums went from
not matching to matching. OK to install?
Thanks to Jakub for that recipe btw. It really saved me a lot of
time in tracking down the bug.
Richard
gcc/testsuite/
* lib/target-supports.exp (check_effective_target_mips_loongson_mmi)
(check_effective_target_mips_msa): Add the arguments to the cache
identifier.
(check_effective_target_mpaired_single): Likewise. Use an asm
to test whether -mpaired-single is supported.
(check_mpaired_single_hw_available): Add -mpaired-single.
---
gcc/testsuite/lib/target-supports.exp | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/gcc/testsuite/lib/target-supports.exp
b/gcc/testsuite/lib/target-supports.exp
index 95a48444b16..6f85277f46d 100644
--- a/gcc/testsuite/lib/target-supports.exp
+++ b/gcc/testsuite/lib/target-supports.exp
@@ -1563,8 +1563,10 @@ proc check_effective_target_pie { } {
# Return true if the target supports -mpaired-single (as used on MIPS).
proc check_effective_target_mpaired_single { args } {
- return [check_no_compiler_messages mpaired_single object {
- void foo (void) { }
+ return [check_no_compiler_messages "mpaired_single_$args" object {
+ void foo (void) {
+ asm volatile ("pll.ps $f2,$f4,$f6");
+ }
} "$args"]
}
@@ -3100,7 +3102,7 @@ proc check_mpaired_single_hw_available { } {
asm volatile ("pll.ps $f2,$f4,$f6");
return 0;
}
- } ""
+ } "-mpaired-single"
}
}]
}
@@ -7665,7 +7667,7 @@ proc add_options_for_mips_loongson_mmi { flags } {
# the Loongson vector modes.
proc check_effective_target_mips_loongson_mmi { args } {
- return [check_no_compiler_messages loongson assembly {
+ return [check_no_compiler_messages "loongson_$args" assembly {
#if !defined(__mips_loongson_mmi)
#error !__mips_loongson_mmi
#endif
@@ -7690,7 +7692,7 @@ proc check_effective_target_mips_msa { args } {
if ![check_effective_target_nomips16] {
return 0
}
- return [check_no_compiler_messages msa object {
+ return [check_no_compiler_messages "msa_$args" object {
#if !defined(__mips_msa)
#error "MSA NOT AVAIL"
#else
--
2.53.0
