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| author | Richard Biener <rguenther@suse.de> | 2020-01-09 10:29:54 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2020-01-09 10:29:54 +0000 |
| commit | 0f507a365777b403cf058ee1208bf41a7363a728 (patch) | |
| tree | 2ac67cd46c37d7d68318fff8b178482191736862 /gcc | |
| parent | ddc8786f8ebe5c97331cbbeef15c99e4878e669e (diff) | |
| download | gcc-0f507a365777b403cf058ee1208bf41a7363a728.zip gcc-0f507a365777b403cf058ee1208bf41a7363a728.tar.gz gcc-0f507a365777b403cf058ee1208bf41a7363a728.tar.bz2 | |
re PR tree-optimization/93040 (gcc doesn't optimize unaligned accesses to a 16-bit value on the x86 as well as it does a 32-bit value (or clang))
2020-01-09 Richard Biener <rguenther@suse.de>
PR tree-optimization/93040
* gimple-ssa-store-merging.c (find_bswap_or_nop): Raise search limit.
* gcc.dg/optimize-bswaphi-1.c: Amend.
* gcc.dg/optimize-bswapsi-2.c: Likewise.
From-SVN: r280034
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/gimple-ssa-store-merging.c | 4 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/optimize-bswaphi-1.c | 8 | ||||
| -rw-r--r-- | gcc/testsuite/gcc.dg/optimize-bswapsi-2.c | 13 |
5 files changed, 32 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4a8e897..dbac2a4 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2020-01-09 Richard Biener <rguenther@suse.de> + + PR tree-optimization/93040 + * gimple-ssa-store-merging.c (find_bswap_or_nop): Raise search limit. + 2020-01-09 Georg-Johann Lay <avr@gjlay.de> * common/config/avr/avr-common.c (avr_option_optimization_table) diff --git a/gcc/gimple-ssa-store-merging.c b/gcc/gimple-ssa-store-merging.c index 0d7639c..741b1ec 100644 --- a/gcc/gimple-ssa-store-merging.c +++ b/gcc/gimple-ssa-store-merging.c @@ -848,11 +848,11 @@ find_bswap_or_nop (gimple *stmt, struct symbolic_number *n, bool *bswap) { /* The last parameter determines the depth search limit. It usually correlates directly to the number n of bytes to be touched. We - increase that number by log2(n) + 1 here in order to also + increase that number by 2 * (log2(n) + 1) here in order to also cover signed -> unsigned conversions of the src operand as can be seen in libgcc, and for initial shift/and operation of the src operand. */ int limit = TREE_INT_CST_LOW (TYPE_SIZE_UNIT (gimple_expr_type (stmt))); - limit += 1 + (int) ceil_log2 ((unsigned HOST_WIDE_INT) limit); + limit += 2 * (1 + (int) ceil_log2 ((unsigned HOST_WIDE_INT) limit)); gimple *ins_stmt = find_bswap_or_nop_1 (stmt, n, limit); if (!ins_stmt) diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index b4e4f83..0e18082 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,9 @@ +2020-01-09 Richard Biener <rguenther@suse.de> + + PR tree-optimization/93040 + * gcc.dg/optimize-bswaphi-1.c: Amend. + * gcc.dg/optimize-bswapsi-2.c: Likewise. + 2020-01-09 Jakub Jelinek <jakub@redhat.com> PR inline-asm/93202 diff --git a/gcc/testsuite/gcc.dg/optimize-bswaphi-1.c b/gcc/testsuite/gcc.dg/optimize-bswaphi-1.c index dcd3c28..e9338d6 100644 --- a/gcc/testsuite/gcc.dg/optimize-bswaphi-1.c +++ b/gcc/testsuite/gcc.dg/optimize-bswaphi-1.c @@ -54,5 +54,11 @@ swap16 (HItype in) | (((in >> 8) & 0xFF) << 0); } -/* { dg-final { scan-tree-dump-times "16 bit load in target endianness found at" 3 "bswap" } } */ +unsigned short +get_unaligned_16 (unsigned char *p) +{ + return p[0] | (p[1] << 8); +} + +/* { dg-final { scan-tree-dump-times "16 bit load in target endianness found at" 4 "bswap" } } */ /* { dg-final { scan-tree-dump-times "16 bit bswap implementation found at" 4 "bswap" } } */ diff --git a/gcc/testsuite/gcc.dg/optimize-bswapsi-2.c b/gcc/testsuite/gcc.dg/optimize-bswapsi-2.c index 30e677b..f111553 100644 --- a/gcc/testsuite/gcc.dg/optimize-bswapsi-2.c +++ b/gcc/testsuite/gcc.dg/optimize-bswapsi-2.c @@ -44,5 +44,16 @@ uint32_t read_be32_3 (unsigned char *data) | (*data << 24); } -/* { dg-final { scan-tree-dump-times "32 bit load in target endianness found at" 3 "bswap" } } */ +static inline unsigned short +get_unaligned_16 (unsigned char *p) +{ + return p[0] | (p[1] << 8); +} +unsigned int +get_unaligned_32 (unsigned char *p) +{ + return get_unaligned_16 (p) | (get_unaligned_16 (p + 2) << 16); +} + +/* { dg-final { scan-tree-dump-times "32 bit load in target endianness found at" 4 "bswap" } } */ /* { dg-final { scan-tree-dump-times "32 bit bswap implementation found at" 3 "bswap" } } */ |