[PATCH 02/46] tcg/optimize: Copy mask writeback to fold_masks

[Richard Henderson]

Use of fold_masks should be restricted to those opcodes that
can reliably make use of it -- those with a single output,
and from higher-level folders that set up the masks.
Prepare for conversion of each folder in turn.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/optimize.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 20c918e83b..1a9e3258e3 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -1050,6 +1050,11 @@ static bool fold_masks(OptContext *ctx, TCGOp *op)
     uint64_t a_mask = ctx->a_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;
+
+    /* Only single-output opcodes are supported here. */
+    tcg_debug_assert(def->nb_oargs == 1);
 
     /*
      * 32-bit ops generate 32-bit results, which for the purpose of
@@ -1062,8 +1067,6 @@ static bool fold_masks(OptContext *ctx, TCGOp *op)
         a_mask = (int32_t)a_mask;
         z_mask = (int32_t)z_mask;
         s_mask |= MAKE_64BIT_MASK(32, 32);
-        ctx->z_mask = z_mask;
-        ctx->s_mask = s_mask;
     }
 
     if (z_mask == 0) {
@@ -1072,7 +1075,12 @@ static bool fold_masks(OptContext *ctx, TCGOp *op)
     if (a_mask == 0) {
         return tcg_opt_gen_mov(ctx, op, op->args[0], op->args[1]);
     }
-    return false;
+
+    ts = arg_temp(op->args[0]);
+    reset_ts(ctx, ts);
+    ts_info(ts)->z_mask = z_mask;
+    ts_info(ts)->s_mask = s_mask;
+    return true;
 }
 
 /*
-- 
2.43.0