From 496f4f884716ae061f771a62e44868a32dbd502f Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Mon, 4 May 2020 11:01:08 +0200 Subject: [PATCH] match.pd: Decrease number of nop conversions around bitwise ops [PR94718] On the following testcase, there are in *.optimized dump 14 nop conversions (from signed to unsigned and back), while this patch decreases that number to just 4; for bitwise ops it really doesn't matter if they are performed in signed or unsigned, so the patch (in GIMPLE only, there are some comments about it being undesirable during GENERIC earlier), if it sees both bitop operands nop converted from the same types performs the bitop in their non-converted type and converts the result (i.e. 2 conversions into 1), similarly, if a bitop has one operand nop converted from something, the other not and the result is converted back to the type of the nop converted operand before conversion, it is possible to replace those 2 conversions with just a single conversion of the other operand. 2020-05-04 Jakub Jelinek PR tree-optimization/94718 * match.pd (bitop (convert @0) (convert? @1)): For GIMPLE, if we can, replace two nop conversions on bit_{and,ior,xor} argument and result with just one conversion on the result or another argument. * gcc.dg/tree-ssa/pr94718-3.c: New test. --- gcc/ChangeLog | 5 +++ gcc/match.pd | 22 +++++++++-- gcc/testsuite/ChangeLog | 3 ++ gcc/testsuite/gcc.dg/tree-ssa/pr94718-3.c | 45 +++++++++++++++++++++++ 4 files changed, 72 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/pr94718-3.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 47eef982a59..036a4030308 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,10 @@ 2020-05-04 Jakub Jelinek + PR tree-optimization/94718 + * match.pd (bitop (convert @0) (convert? @1)): For GIMPLE, if we can, + replace two nop conversions on bit_{and,ior,xor} argument + and result with just one conversion on the result or another argument. + PR tree-optimization/94718 * fold-const.c (fold_binary_loc): Move (X & C) eqne (Y & C) -> (X ^ Y) & C eqne 0 optimization to ... diff --git a/gcc/match.pd b/gcc/match.pd index 123e670f9ee..929be14e8b7 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -1311,7 +1311,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) We combine the above two cases by using a conditional convert. */ (for bitop (bit_and bit_ior bit_xor) (simplify - (bitop (convert @0) (convert? @1)) + (bitop (convert@2 @0) (convert?@3 @1)) (if (((TREE_CODE (@1) == INTEGER_CST && INTEGRAL_TYPE_P (TREE_TYPE (@0)) && int_fits_type_p (@1, TREE_TYPE (@0))) @@ -1330,8 +1330,24 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) || GET_MODE_CLASS (TYPE_MODE (type)) != MODE_INT /* Or if the precision of TO is not the same as the precision of its mode. */ - || !type_has_mode_precision_p (type))) - (convert (bitop @0 (convert @1)))))) + || !type_has_mode_precision_p (type) + /* In GIMPLE, getting rid of 2 conversions for one new results + in smaller IL. */ + || (GIMPLE + && TREE_CODE (@1) != INTEGER_CST + && tree_nop_conversion_p (type, TREE_TYPE (@0)) + && single_use (@2) + && single_use (@3)))) + (convert (bitop @0 (convert @1))))) + /* In GIMPLE, getting rid of 2 conversions for one new results + in smaller IL. */ + (simplify + (convert (bitop:cs@2 (nop_convert:s @0) @1)) + (if (GIMPLE + && TREE_CODE (@1) != INTEGER_CST + && tree_nop_conversion_p (type, TREE_TYPE (@2)) + && types_match (type, @0)) + (bitop @0 (convert @1))))) (for bitop (bit_and bit_ior) rbitop (bit_ior bit_and) diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 100870acedb..09979b5749c 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,5 +1,8 @@ 2020-05-04 Jakub Jelinek + PR tree-optimization/94718 + * gcc.dg/tree-ssa/pr94718-3.c: New test. + PR tree-optimization/94718 * gcc.dg/tree-ssa/pr94718-1.c: New test. * gcc.dg/tree-ssa/pr94718-2.c: New test. diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr94718-3.c b/gcc/testsuite/gcc.dg/tree-ssa/pr94718-3.c new file mode 100644 index 00000000000..d1fb4a64504 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr94718-3.c @@ -0,0 +1,45 @@ +/* PR tree-optimization/94718 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fno-ipa-icf -fdump-tree-optimized" } */ +/* { dg-final { scan-tree-dump-times " \\\(int\\\) " 2 "optimized" } } */ +/* { dg-final { scan-tree-dump-times " \\\(unsigned int\\\) " 2 "optimized" } } */ + +int +f1 (int x, int y) +{ + return (int) ((unsigned) x | (unsigned) y); +} + +int +f2 (int x, int y) +{ + unsigned a = x; + unsigned b = y; + return a | b; +} + +int +f3 (int x, unsigned y) +{ + return (int) ((unsigned) x | y); +} + +int +f4 (int x, unsigned y) +{ + unsigned a = x; + return a | y; +} + +unsigned +f5 (int x, unsigned y) +{ + return (unsigned) (x | (int) y); +} + +unsigned +f6 (int x, unsigned y) +{ + int a = y; + return x | a; +} -- 2.30.2