From a10d70babdbb3018f3ad9824b2158779844a7999 Mon Sep 17 00:00:00 2001 From: Pat Haugen Date: Fri, 25 Mar 2005 20:08:30 +0000 Subject: [PATCH] re PR tree-optimization/20470 (Branching sequence generated for ABS(x-y)) 2005-03-25 Pat Haugen PR tree-optimization/20470 * fold-const.c (fold_cond_expr_with_comparison): Recognize/fold ABS(x-y). From-SVN: r97062 --- gcc/ChangeLog | 6 ++++++ gcc/fold-const.c | 12 ++++++++++-- 2 files changed, 16 insertions(+), 2 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 4a096a0b9d8..71e4822bf08 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2005-03-25 Pat Haugen + + PR tree-optimization/20470 + * fold-const.c (fold_cond_expr_with_comparison): Recognize/fold + ABS(x-y). + 2005-03-25 Mike Stump * config/darwin.h (ASM_OUTPUT_ALIGNED_DECL_LOCAL): Don't allow 0 diff --git a/gcc/fold-const.c b/gcc/fold-const.c index d32172f2453..4ac921b3a55 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -4187,8 +4187,16 @@ fold_cond_expr_with_comparison (tree type, tree arg0, tree arg1, tree arg2) if ((FLOAT_TYPE_P (TREE_TYPE (arg01)) ? real_zerop (arg01) : integer_zerop (arg01)) - && TREE_CODE (arg2) == NEGATE_EXPR - && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) + && ((TREE_CODE (arg2) == NEGATE_EXPR + && operand_equal_p (TREE_OPERAND (arg2, 0), arg1, 0)) + /* In the case that A is of the form X-Y, '-A' (arg2) may + have already been folded to Y-X, check for that. */ + || (TREE_CODE (arg1) == MINUS_EXPR + && TREE_CODE (arg2) == MINUS_EXPR + && operand_equal_p (TREE_OPERAND (arg1, 0), + TREE_OPERAND (arg2, 1), 0) + && operand_equal_p (TREE_OPERAND (arg1, 1), + TREE_OPERAND (arg2, 0), 0)))) switch (comp_code) { case EQ_EXPR: