tcg/optimize: Fold movcond with true and false values identical

Fold "x = cond ? y : y" to "x = y".

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This commit is contained in:
Richard Henderson 2024-09-06 21:00:10 -07:00
parent fcc54e7bf5
commit 141125e08c

View file

@ -1851,6 +1851,11 @@ static bool fold_movcond(OptContext *ctx, TCGOp *op)
{
int i;
/* If true and false values are the same, eliminate the cmp. */
if (args_are_copies(op->args[3], op->args[4])) {
return tcg_opt_gen_mov(ctx, op, op->args[0], op->args[3]);
}
/*
* Canonicalize the "false" input reg to match the destination reg so
* that the tcg backend can implement a "move if true" operation.