From: Richard Henderson <richard.henderson@linaro.org>
Date: Mon, 25 Oct 2021 18:30:14 +0000 (-0700)
Subject: tcg/optimize: Use fold_xi_to_x for div
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=2f9d9a34221feb80d5b1fc6b584f910f8cee317a;p=qmiga%2Fqemu.git

tcg/optimize: Use fold_xi_to_x for div

Recognize the identity function for division.

Suggested-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---

diff --git a/tcg/optimize.c b/tcg/optimize.c
index 907049fb06..f8b0709157 100644
--- a/tcg/optimize.c
+++ b/tcg/optimize.c
@@ -1218,7 +1218,11 @@ static bool fold_deposit(OptContext *ctx, TCGOp *op)
 
 static bool fold_divide(OptContext *ctx, TCGOp *op)
 {
-    return fold_const2(ctx, op);
+    if (fold_const2(ctx, op) ||
+        fold_xi_to_x(ctx, op, 1)) {
+        return true;
+    }
+    return false;
 }
 
 static bool fold_dup(OptContext *ctx, TCGOp *op)