On Tue, 7 Jul 2015, Hurugalawadi, Naveen wrote:
Please find attached the patch "PR25529.patch" that converts the pattern:- (unsigned * 2)/2 is into unsigned &0x7FFFFFFF
+/* Simplify (unsigned t * 2)/2 -> unsigned t & 0x7FFFFFFF. */ +(for div (trunc_div ceil_div floor_div round_div exact_div) + (simplify + (div (mult @0 INTEGER_CST@1) INTEGER_CST@1) You don't need to repeat INTEGER_CST, the second time @1 is enough. + (with { tree n2 = build_int_cst (TREE_TYPE (@0), + wi::exact_log2 (@1)); } + (if (TYPE_UNSIGNED (TREE_TYPE (@0))) + (bit_and @0 (rshift (lshift { build_minus_one_cst (TREE_TYPE (@0)); } + { n2; }) { n2; })))))) What happens if you write t*3/3? -- Marc Glisse