tcg/optimize: Split out fold_masks_zs

Add a routine to which masks can be passed directly, rather than
storing them into OptContext.  To be used in upcoming patches.

Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 12 insertions, 3 deletions

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 2aa57af..d70127b 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -1044,10 +1044,14 @@ static bool fold_const2_commutative(OptContext *ctx, TCGOp *op)
     return fold_const2(ctx, op);
 }
 
-static bool fold_masks(OptContext *ctx, TCGOp *op)
+/*
+ * Record "zero" and "sign" masks for the single output of @op.
+ * See TempOptInfo definition of z_mask and s_mask.
+ * If z_mask allows, fold the output to constant zero.
+ */
+static bool fold_masks_zs(OptContext *ctx, TCGOp *op,
+                          uint64_t z_mask, uint64_t s_mask)
 {
-    uint64_t z_mask = ctx->z_mask;
-    uint64_t s_mask = ctx->s_mask;
     const TCGOpDef *def = &tcg_op_defs[op->opc];
     TCGTemp *ts;
     TempOptInfo *ti;
@@ -1080,6 +1084,11 @@ static bool fold_masks(OptContext *ctx, TCGOp *op)
     return true;
 }
 
+static bool fold_masks(OptContext *ctx, TCGOp *op)
+{
+    return fold_masks_zs(ctx, op, ctx->z_mask, ctx->s_mask);
+}
+
 /*
  * An "affected" mask bit is 0 if and only if the result is identical
  * to the first input.  Thus if the entire mask is 0, the operation