From 187dd955dbee3939c3a2ca7b6839e7f709999125 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Sat, 15 Feb 2020 12:53:44 +0100 Subject: [PATCH] match.pd: Disallow side-effects in GENERIC for non-COND_EXPR to COND_EXPR simplifications [PR93744] As the following testcases show (the first one reported, last two found by code inspection), we need to disallow side-effects in simplifications that turn some unconditional expression into conditional one. From my little understanding of genmatch.c, it is able to automatically disallow side effects if the same operand is used multiple times in the match pattern, maybe if it is used multiple times in the replacement pattern, and if it is used in conditional contexts in the match pattern, could it be taught to handle this case too? If yes, perhaps just the first hunk could be usable for 8/9 backports (+ the testcases). 2020-02-15 Jakub Jelinek PR tree-optimization/93744 * match.pd (((m1 >/=/<= m2) * d -> (m1 >/=/<= m2) ? d : 0, A - ((A - B) & -(C cmp D)) -> (C cmp D) ? B : A, A + ((B - A) & -(C cmp D)) -> (C cmp D) ? B : A): For GENERIC, make sure @2 in the first and @1 in the other patterns has no side-effects. * gcc.c-torture/execute/pr93744-1.c: New test. * gcc.c-torture/execute/pr93744-2.c: New test. * gcc.c-torture/execute/pr93744-3.c: New test. --- gcc/ChangeLog | 8 +++++++ gcc/match.pd | 9 +++++--- gcc/testsuite/ChangeLog | 7 +++++++ .../gcc.c-torture/execute/pr93744-1.c | 14 +++++++++++++ .../gcc.c-torture/execute/pr93744-2.c | 21 +++++++++++++++++++ .../gcc.c-torture/execute/pr93744-3.c | 21 +++++++++++++++++++ 6 files changed, 77 insertions(+), 3 deletions(-) create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr93744-1.c create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr93744-2.c create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr93744-3.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 22f990a3088..3ef5b4d68f7 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2020-02-15 Jakub Jelinek + + PR tree-optimization/93744 + * match.pd (((m1 >/=/<= m2) * d -> (m1 >/=/<= m2) ? d : 0, + A - ((A - B) & -(C cmp D)) -> (C cmp D) ? B : A, + A + ((B - A) & -(C cmp D)) -> (C cmp D) ? B : A): For GENERIC, make + sure @2 in the first and @1 in the other patterns has no side-effects. + 2020-02-15 David Malcolm Bernd Edlinger diff --git a/gcc/match.pd b/gcc/match.pd index 73834c25593..19df0c404a4 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -1472,7 +1472,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) (for cmp (gt lt ge le) (simplify (mult (convert (cmp @0 @1)) @2) - (cond (cmp @0 @1) @2 { build_zero_cst (type); }))) + (if (GIMPLE || !TREE_SIDE_EFFECTS (@2)) + (cond (cmp @0 @1) @2 { build_zero_cst (type); })))) /* For integral types with undefined overflow and C != 0 fold x * C EQ/NE y * C into x EQ/NE y. */ @@ -2709,7 +2710,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) && TREE_CODE (TREE_TYPE (@4)) != BOOLEAN_TYPE && INTEGRAL_TYPE_P (TREE_TYPE (@5)) && (TYPE_PRECISION (TREE_TYPE (@4)) >= TYPE_PRECISION (type) - || !TYPE_UNSIGNED (TREE_TYPE (@4)))) + || !TYPE_UNSIGNED (TREE_TYPE (@4))) + && (GIMPLE || !TREE_SIDE_EFFECTS (@1))) (cond (cmp @2 @3) @1 @0))) (simplify (plus:c @0 (bit_and:c (minus @1 @0) @@ -2719,7 +2721,8 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) && TREE_CODE (TREE_TYPE (@4)) != BOOLEAN_TYPE && INTEGRAL_TYPE_P (TREE_TYPE (@5)) && (TYPE_PRECISION (TREE_TYPE (@4)) >= TYPE_PRECISION (type) - || !TYPE_UNSIGNED (TREE_TYPE (@4)))) + || !TYPE_UNSIGNED (TREE_TYPE (@4))) + && (GIMPLE || !TREE_SIDE_EFFECTS (@1))) (cond (cmp @2 @3) @1 @0)))) /* Simplifications of shift and rotates. */ diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 3059e238ff3..77c781a40e8 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,10 @@ +2020-02-15 Jakub Jelinek + + PR tree-optimization/93744 + * gcc.c-torture/execute/pr93744-1.c: New test. + * gcc.c-torture/execute/pr93744-2.c: New test. + * gcc.c-torture/execute/pr93744-3.c: New test. + 2020-02-14 Jakub Jelinek PR c++/61414 diff --git a/gcc/testsuite/gcc.c-torture/execute/pr93744-1.c b/gcc/testsuite/gcc.c-torture/execute/pr93744-1.c new file mode 100644 index 00000000000..3229c9b2bd6 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr93744-1.c @@ -0,0 +1,14 @@ +/* PR tree-optimization/93744 */ + +typedef int I; + +int +main () +{ + int a = 0; + I b = 0; + (a > 0) * (b |= 2); + if (b != 2) + __builtin_abort (); + return 0; +} diff --git a/gcc/testsuite/gcc.c-torture/execute/pr93744-2.c b/gcc/testsuite/gcc.c-torture/execute/pr93744-2.c new file mode 100644 index 00000000000..0c1baaac77b --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr93744-2.c @@ -0,0 +1,21 @@ +/* PR tree-optimization/93744 */ + +int w; + +int +foo (int x, int y, int z) +{ + int r = z - ((z - w++) & -(x < y)); + return r; +} + +int +main () +{ + w = 4; + if (foo (5, 7, 12) != 4 || w != 5) + __builtin_abort (); + if (foo (7, 5, 12) != 12 || w != 6) + __builtin_abort (); + return 0; +} diff --git a/gcc/testsuite/gcc.c-torture/execute/pr93744-3.c b/gcc/testsuite/gcc.c-torture/execute/pr93744-3.c new file mode 100644 index 00000000000..8542c7c53ba --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr93744-3.c @@ -0,0 +1,21 @@ +/* PR tree-optimization/93744 */ + +int w; + +int +foo (int x, int y, int z) +{ + int r = z + ((w++ - z) & -(x < y)); + return r; +} + +int +main () +{ + w = 4; + if (foo (5, 7, 12) != 4 || w != 5) + __builtin_abort (); + if (foo (7, 5, 12) != 12 || w != 6) + __builtin_abort (); + return 0; +} -- 2.30.2