From 139c978a44cbf1a53186af94715de74b83c542dc Mon Sep 17 00:00:00 2001 From: Jeff Law Date: Fri, 28 Jan 2005 09:35:46 -0700 Subject: fold-const.c (fold, [...]): Optimize 0 % X. * fold-const.c (fold, case CEIL_MOD_EXPR): Optimize 0 % X. (case FLOOR_MOD_EXPR, ROUND_MOD_EXPR, TRUNC_MOD_EXPR): Similarly. From-SVN: r94376 --- gcc/ChangeLog | 5 +++++ gcc/fold-const.c | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-) (limited to 'gcc') diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 8aac434..9e806b3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2005-01-28 Jeff Law + + * fold-const.c (fold, case CEIL_MOD_EXPR): Optimize 0 % X. + (case FLOOR_MOD_EXPR, ROUND_MOD_EXPR, TRUNC_MOD_EXPR): Similarly. + 2005-01-28 Kazu Hirata * cse.c (cse_reg_info_free_list, cse_reg_info_used_list, diff --git a/gcc/fold-const.c b/gcc/fold-const.c index 8e8a821..67a0217 100644 --- a/gcc/fold-const.c +++ b/gcc/fold-const.c @@ -7875,7 +7875,8 @@ fold (tree expr) case FLOOR_MOD_EXPR: case ROUND_MOD_EXPR: case TRUNC_MOD_EXPR: - if (integer_onep (arg1)) + /* 0 % X is always zero as is X % 1. */ + if (integer_zerop (arg0) || integer_onep (arg1)) return omit_one_operand (type, integer_zero_node, arg0); if (integer_zerop (arg1)) return t; -- cgit v1.1