Currently these bswap testcases use global variables, which causes problems with -m32: the memory access is a D-form access, and when combine tries to combine that with the bswap it tries a D-form store with byte reverse. That instruction does not exist, and since combine started with only two insns here it will not try splitting this.
This should be improved, but it is not what this test is testing, and the "load" case already uses a pointer, so let's do that for the store case as well. 2019-03-18 Segher Boessenkool <seg...@kernel.crashing.org> gcc/testsuite/ * gcc.target/powerpc/bswap16.c: Use a pointer instead of a global for the "store" test as well. * gcc.target/powerpc/bswap32.c: Ditto. --- gcc/testsuite/gcc.target/powerpc/bswap16.c | 3 +-- gcc/testsuite/gcc.target/powerpc/bswap32.c | 3 +-- 2 files changed, 2 insertions(+), 4 deletions(-) diff --git a/gcc/testsuite/gcc.target/powerpc/bswap16.c b/gcc/testsuite/gcc.target/powerpc/bswap16.c index 5eea4f7..89efc811 100644 --- a/gcc/testsuite/gcc.target/powerpc/bswap16.c +++ b/gcc/testsuite/gcc.target/powerpc/bswap16.c @@ -3,6 +3,5 @@ /* { dg-final { scan-assembler "lhbrx" } } */ /* { dg-final { scan-assembler "sthbrx" } } */ -unsigned short us; unsigned int load_bswap16 (unsigned short *p) { return __builtin_bswap16 (*p); } -void store_bswap16 (unsigned int a) { us = __builtin_bswap16 (a); } +void store_bswap16 (unsigned short *p, unsigned int a) { *p = __builtin_bswap16 (a); } diff --git a/gcc/testsuite/gcc.target/powerpc/bswap32.c b/gcc/testsuite/gcc.target/powerpc/bswap32.c index 1b1e189..0d1788f 100644 --- a/gcc/testsuite/gcc.target/powerpc/bswap32.c +++ b/gcc/testsuite/gcc.target/powerpc/bswap32.c @@ -3,6 +3,5 @@ /* { dg-final { scan-assembler "lwbrx" } } */ /* { dg-final { scan-assembler "stwbrx" } } */ -unsigned int ui; unsigned int load_bswap32 (unsigned int *p) { return __builtin_bswap32 (*p); } -void store_bswap32 (unsigned int a) { ui = __builtin_bswap32 (a); } +void store_bswap32 (unsigned int *p, unsigned int a) { *p = __builtin_bswap32 (a); } -- 1.8.3.1