From 23ec69ed3759fe5d8374cb22795ade1305c331c4 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 28 Jan 2014 12:03:24 -0800 Subject: tcg/optimize: Handle known-zeros masks for ANDC Reviewed-by: Paolo Bonzini Reviewed-by: Aurelien Jarno Signed-off-by: Richard Henderson --- tcg/optimize.c | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'tcg') diff --git a/tcg/optimize.c b/tcg/optimize.c index 1b9fea5a3d..4bea8a56ef 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -727,6 +727,17 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, mask = temps[args[1]].mask & mask; break; + CASE_OP_32_64(andc): + /* Known-zeros does not imply known-ones. Therefore unless + args[2] is constant, we can't infer anything from it. */ + if (temps[args[2]].state == TCG_TEMP_CONST) { + mask = ~temps[args[2]].mask; + goto and_const; + } + /* But we certainly know nothing outside args[1] may be set. */ + mask = temps[args[1]].mask; + break; + case INDEX_op_sar_i32: if (temps[args[2]].state == TCG_TEMP_CONST) { mask = (int32_t)temps[args[1]].mask >> temps[args[2]].val; -- cgit v1.2.1