From: Richard Henderson <richard.henderson@linaro.org>
Date: Sat, 25 Feb 2023 22:29:41 +0000 (-1000)
Subject: target/arm: Avoid tcg_const_ptr in handle_rev
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=56649fd949a85973c23ae17285de7ce5ffe18656;p=qemu.git

target/arm: Avoid tcg_const_ptr in handle_rev

Here it is not trivial to notice first initialization, so explicitly
zero the temps.  Use an array for the output, rather than separate
tcg_rd/tcg_rd_hi variables.

Fixes a bug by adding a missing clear_vec_high.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 082a8b82dd..dff391bfe2 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -12003,22 +12003,26 @@ static void handle_rev(DisasContext *s, int opcode, bool u,
         int esize = 8 << size;
         int elements = dsize / esize;
         TCGv_i64 tcg_rn = tcg_temp_new_i64();
-        TCGv_i64 tcg_rd = tcg_const_i64(0);
-        TCGv_i64 tcg_rd_hi = tcg_const_i64(0);
+        TCGv_i64 tcg_rd[2];
+
+        for (i = 0; i < 2; i++) {
+            tcg_rd[i] = tcg_temp_new_i64();
+            tcg_gen_movi_i64(tcg_rd[i], 0);
+        }
 
         for (i = 0; i < elements; i++) {
             int e_rev = (i & 0xf) ^ revmask;
-            int off = e_rev * esize;
+            int w = (e_rev * esize) / 64;
+            int o = (e_rev * esize) % 64;
+
             read_vec_element(s, tcg_rn, rn, i, size);
-            if (off >= 64) {
-                tcg_gen_deposit_i64(tcg_rd_hi, tcg_rd_hi,
-                                    tcg_rn, off - 64, esize);
-            } else {
-                tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_rn, off, esize);
-            }
+            tcg_gen_deposit_i64(tcg_rd[w], tcg_rd[w], tcg_rn, o, esize);
+        }
+
+        for (i = 0; i < 2; i++) {
+            write_vec_element(s, tcg_rd[i], rd, i, MO_64);
         }
-        write_vec_element(s, tcg_rd, rd, 0, MO_64);
-        write_vec_element(s, tcg_rd_hi, rd, 1, MO_64);
+        clear_vec_high(s, true, rd);
     }
 }