diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 6e5396a04a26..4b3d554d3f11 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2005-07-02 Andrew Pinski + + PR middle-end/14490 + * fold-const.c (fold_binary): Handle the return value of + fold_to_nonsharp_ineq_using_bound if we get back the same operand back. + Implement "X +- C1 CMP C2" folding to "X CMP C2 -+ C1". + 2005-07-02 Jeff Law * tree-ssa-dom.c (find_equivalent_equality_comparison): Do not diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 564cec3ec87a..682ae00a08cf 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -8575,11 +8575,11 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) && !TREE_SIDE_EFFECTS (arg1)) { tem = fold_to_nonsharp_ineq_using_bound (arg0, arg1); - if (tem) + if (tem && !operand_equal_p (tem, arg0, 0)) return fold_build2 (code, type, tem, arg1); tem = fold_to_nonsharp_ineq_using_bound (arg1, arg0); - if (tem) + if (tem && !operand_equal_p (tem, arg1, 0)) return fold_build2 (code, type, arg0, tem); } @@ -8865,6 +8865,30 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1) } } + /* Transform comparisons of the form X +- C1 CMP C2 to X CMP C2 +- C1. */ + if ((TREE_CODE (arg0) == PLUS_EXPR || TREE_CODE (arg0) == MINUS_EXPR) + && (TREE_CODE (TREE_OPERAND (arg0, 1)) == INTEGER_CST + && !TREE_OVERFLOW (TREE_OPERAND (arg0, 1)) + && !TYPE_UNSIGNED (TREE_TYPE (arg1)) + && !(flag_wrapv || flag_trapv)) + && (TREE_CODE (arg1) == INTEGER_CST + && !TREE_OVERFLOW (arg1))) + { + tree const1 = TREE_OPERAND (arg0, 1); + tree const2 = arg1; + tree variable = TREE_OPERAND (arg0, 0); + tree lhs; + int lhs_add; + lhs_add = TREE_CODE (arg0) != PLUS_EXPR; + + lhs = fold_build2 (lhs_add ? PLUS_EXPR : MINUS_EXPR, + TREE_TYPE (arg1), const2, const1); + if (TREE_CODE (lhs) == TREE_CODE (arg1) + && (TREE_CODE (lhs) != INTEGER_CST + || !TREE_OVERFLOW (lhs))) + return fold_build2 (code, type, variable, lhs); + } + if (FLOAT_TYPE_P (TREE_TYPE (arg0))) { tree targ0 = strip_float_extensions (arg0); diff --git a/gcc/testsuite/gcc.dg/20050702-1.c b/gcc/testsuite/gcc.dg/20050702-1.c new file mode 100644 index 000000000000..ce151d36131a --- /dev/null +++ b/gcc/testsuite/gcc.dg/20050702-1.c @@ -0,0 +1,24 @@ +/* { dg-do compile } */ +/* { dg-options "-O2" } */ +/* We going into an infinite loop in fold because we + were mishandling the return value of + fold_to_nonsharp_ineq_using_bound. */ +_Bool f(); +void g(int); +void h (int old_size) +{ + int new_size = old_size, i; + g(old_size - 1); + i = 0; + while (i < old_size - 1) + { + if (f()) + { + i++; + continue; + } + while (i < old_size - 1) + i++; + } + g(new_size); +} diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr14490-1.c b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-1.c new file mode 100644 index 000000000000..733367b214cd --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-1.c @@ -0,0 +1,11 @@ +/* { dg-do compile } */ +/* { dg-options "-fdump-tree-gimple" } */ +int g(int x) +{ + return (x - 10) < 0; +} +/* There should be only x >= 9 and no x - 10. */ +/* { dg-final { scan-tree-dump-times ">= 9" 1 "gimple"} } */ +/* { dg-final { scan-tree-dump-times "- 10" 0 "gimple"} } */ +/* { dg-final { cleanup-tree-dump "gimple" } } */ + diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr14490-2.c b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-2.c new file mode 100644 index 000000000000..eaa0f1368f73 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-2.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-fdump-tree-gimple -fwrapv" } */ +int g(int x) +{ + return (x - 10) < 0; +} +/* There should be no x >= 9 and one x - 10. */ +/* { dg-final { scan-tree-dump-times ">= 9" 0 "gimple"} } */ +/* { dg-final { scan-tree-dump-times "- 10" 1 "gimple"} } */ +/* { dg-final { cleanup-tree-dump "gimple" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr14490-3.c b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-3.c new file mode 100644 index 000000000000..0e6873b831d6 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-3.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-fdump-tree-gimple" } */ +int g(int x) +{ + return (x + 10) < 0; +} +/* There should be only x >= -9 and no x + 10. */ +/* { dg-final { scan-tree-dump-times ">= 9" 1 "gimple"} } */ +/* { dg-final { scan-tree-dump-times "- 10" 0 "gimple"} } */ +/* { dg-final { cleanup-tree-dump "gimple" } } */ diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr14490-4.c b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-4.c new file mode 100644 index 000000000000..365ab7771c06 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr14490-4.c @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-fdump-tree-gimple -fwrapv" } */ +int g(int x) +{ + return (x + 10) < 0; +} +/* There should be no x >= -9 and one x + 10. */ +/* { dg-final { scan-tree-dump-times ">= 9" 0 "gimple"} } */ +/* { dg-final { scan-tree-dump-times "- 10" 1 "gimple"} } */ +/* { dg-final { cleanup-tree-dump "gimple" } } */