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author | Thomas Preud'homme <thomas.preudhomme@arm.com> | 2014-03-12 10:15:29 +0000 |
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committer | Jakub Jelinek <jakub@gcc.gnu.org> | 2014-03-12 11:15:29 +0100 |
commit | 882a5fbe3c0e81734257bfd8bc0f5c41a769394b (patch) | |
tree | 9b02b5390b8965759e4404532019e9f29d128bf4 /gcc | |
parent | a3cd024676cbf385396d57b6b1f752040a902779 (diff) | |
download | gcc-882a5fbe3c0e81734257bfd8bc0f5c41a769394b.zip gcc-882a5fbe3c0e81734257bfd8bc0f5c41a769394b.tar.gz gcc-882a5fbe3c0e81734257bfd8bc0f5c41a769394b.tar.bz2 |
re PR tree-optimization/60454 (Code mistakenly detected as doing bswap)
PR tree-optimization/60454
* tree-ssa-math-opts.c (find_bswap_1): Fix bswap detection.
* gcc.c-torture/execute/pr60454.c: New test.
From-SVN: r208509
Diffstat (limited to 'gcc')
-rw-r--r-- | gcc/ChangeLog | 5 | ||||
-rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
-rw-r--r-- | gcc/testsuite/gcc.c-torture/execute/pr60454.c | 31 | ||||
-rw-r--r-- | gcc/tree-ssa-math-opts.c | 11 |
4 files changed, 52 insertions, 0 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index cc980d9..c76fc80 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2014-03-12 Thomas Preud'homme <thomas.preudhomme@arm.com> + + PR tree-optimization/60454 + * tree-ssa-math-opts.c (find_bswap_1): Fix bswap detection. + 2014-03-12 Kyrylo Tkachov <kyrylo.tkachov@arm.com> * config.gcc (aarch64*-*-*): Use ISA flags from aarch64-arches.def. diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 24d0d9a..dde17b0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2014-03-12 Thomas Preud'homme <thomas.preudhomme@arm.com> + + PR tree-optimization/60454 + * gcc.c-torture/execute/pr60454.c: New test. + 2014-03-12 Jakub Jelinek <jakub@redhat.com> Marc Glisse <marc.glisse@inria.fr> diff --git a/gcc/testsuite/gcc.c-torture/execute/pr60454.c b/gcc/testsuite/gcc.c-torture/execute/pr60454.c new file mode 100644 index 0000000..ceec45e --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr60454.c @@ -0,0 +1,31 @@ +#ifdef __UINT32_TYPE__ +typedef __UINT32_TYPE__ uint32_t; +#else +typedef unsigned uint32_t; +#endif + +#define __fake_const_swab32(x) ((uint32_t)( \ + (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 24) | \ + (((uint32_t)(x) & (uint32_t)0x0000ff00UL) << 8) | \ + (((uint32_t)(x) & (uint32_t)0x000000ffUL) << 8) | \ + (((uint32_t)(x) & (uint32_t)0x0000ff00UL) ) | \ + (((uint32_t)(x) & (uint32_t)0xff000000UL) >> 24))) + +/* Previous version of bswap optimization would detect byte swap when none + happen. This test aims at catching such wrong detection to avoid + regressions. */ + +__attribute__ ((noinline, noclone)) uint32_t +fake_swap32 (uint32_t in) +{ + return __fake_const_swab32 (in); +} + +int main(void) +{ + if (sizeof (uint32_t) * __CHAR_BIT__ != 32) + return 0; + if (fake_swap32 (0x12345678UL) != 0x78567E12UL) + __builtin_abort (); + return 0; +} diff --git a/gcc/tree-ssa-math-opts.c b/gcc/tree-ssa-math-opts.c index 8e372ed..9ff857c 100644 --- a/gcc/tree-ssa-math-opts.c +++ b/gcc/tree-ssa-math-opts.c @@ -1801,7 +1801,9 @@ find_bswap_1 (gimple stmt, struct symbolic_number *n, int limit) if (rhs_class == GIMPLE_BINARY_RHS) { + int i; struct symbolic_number n1, n2; + unsigned HOST_WIDEST_INT mask; tree source_expr2; if (code != BIT_IOR_EXPR) @@ -1827,6 +1829,15 @@ find_bswap_1 (gimple stmt, struct symbolic_number *n, int limit) return NULL_TREE; n->size = n1.size; + for (i = 0, mask = 0xff; i < n->size; i++, mask <<= BITS_PER_UNIT) + { + unsigned HOST_WIDEST_INT masked1, masked2; + + masked1 = n1.n & mask; + masked2 = n2.n & mask; + if (masked1 && masked2 && masked1 != masked2) + return NULL_TREE; + } n->n = n1.n | n2.n; if (!verify_symbolic_number_p (n, stmt)) |