From 5d8f53630011f93dc774f1b2dc9557c7eac3ad89 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Fri, 21 Sep 2012 10:13:38 -0700 Subject: [PATCH] tcg: Optimize two-address commutative operations While swapping constants to the second operand, swap sources matching destinations to the first operand. Signed-off-by: Richard Henderson Signed-off-by: Aurelien Jarno --- tcg/optimize.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/tcg/optimize.c b/tcg/optimize.c index 26038a695d..1be7631672 100644 --- a/tcg/optimize.c +++ b/tcg/optimize.c @@ -334,6 +334,8 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, const TCGOpDef *def; TCGArg *gen_args; TCGArg tmp; + TCGCond cond; + /* Array VALS has an element for each temp. If this temp holds a constant then its value is kept in VALS' element. If this temp is a copy of other ones then this equivalence class' @@ -395,13 +397,24 @@ static TCGArg *tcg_constant_folding(TCGContext *s, uint16_t *tcg_opc_ptr, } break; CASE_OP_32_64(movcond): + cond = args[5]; if (temps[args[1]].state == TCG_TEMP_CONST && temps[args[2]].state != TCG_TEMP_CONST) { tmp = args[1]; args[1] = args[2]; args[2] = tmp; - args[5] = tcg_swap_cond(args[5]); + cond = tcg_swap_cond(cond); + } + /* For movcond, we canonicalize the "false" input reg to match + the destination reg so that the tcg backend can implement + a "move if true" operation. */ + if (args[0] == args[3]) { + tmp = args[3]; + args[3] = args[4]; + args[4] = tmp; + cond = tcg_invert_cond(cond); } + args[5] = cond; default: break; } -- GitLab