tcg/optimize: Split out finish_folding

Copy z_mask into OptContext, for writeback to the
first output within the new function.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 33 insertions, 16 deletions

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 066e635..368457f 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -48,6 +48,9 @@ typedef struct OptContext {
     TCGContext *tcg;
     TCGOp *prev_mb;
     TCGTempSet temps_used;
+
+    /* In flight values from optimization. */
+    uint64_t z_mask;
 } OptContext;
 
 static inline TempOptInfo *ts_info(TCGTemp *ts)
@@ -629,6 +632,34 @@ static void copy_propagate(OptContext *ctx, TCGOp *op,
     }
 }
 
+static void finish_folding(OptContext *ctx, TCGOp *op)
+{
+    const TCGOpDef *def = &tcg_op_defs[op->opc];
+    int i, nb_oargs;
+
+    /*
+     * For an opcode that ends a BB, reset all temp data.
+     * We do no cross-BB optimization.
+     */
+    if (def->flags & TCG_OPF_BB_END) {
+        memset(&ctx->temps_used, 0, sizeof(ctx->temps_used));
+        ctx->prev_mb = NULL;
+        return;
+    }
+
+    nb_oargs = def->nb_oargs;
+    for (i = 0; i < nb_oargs; i++) {
+        reset_temp(op->args[i]);
+        /*
+         * Save the corresponding known-zero bits mask for the
+         * first output argument (only one supported so far).
+         */
+        if (i == 0) {
+            arg_info(op->args[i])->z_mask = ctx->z_mask;
+        }
+    }
+}
+
 static bool fold_call(OptContext *ctx, TCGOp *op)
 {
     TCGContext *s = ctx->tcg;
@@ -1122,6 +1153,7 @@ void tcg_optimize(TCGContext *s)
             partmask &= 0xffffffffu;
             affected &= 0xffffffffu;
         }
+        ctx.z_mask = z_mask;
 
         if (partmask == 0) {
             tcg_opt_gen_movi(&ctx, op, op->args[0], 0);
@@ -1570,22 +1602,7 @@ void tcg_optimize(TCGContext *s)
             break;
         }
 
-        /* Some of the folding above can change opc. */
-        opc = op->opc;
-        def = &tcg_op_defs[opc];
-        if (def->flags & TCG_OPF_BB_END) {
-            memset(&ctx.temps_used, 0, sizeof(ctx.temps_used));
-        } else {
-            int nb_oargs = def->nb_oargs;
-            for (i = 0; i < nb_oargs; i++) {
-                reset_temp(op->args[i]);
-                /* Save the corresponding known-zero bits mask for the
-                   first output argument (only one supported so far). */
-                if (i == 0) {
-                    arg_info(op->args[i])->z_mask = z_mask;
-                }
-            }
-        }
+        finish_folding(&ctx, op);
 
         /* Eliminate duplicate and redundant fence instructions.  */
         if (ctx.prev_mb) {