[Qemu-devel] [PATCH] target-ppc: Fix xxpermdi When T==A or T==B

[Tom Musta]

The existing implementation of xxpermdi is defective if the target
VSR is also a source VSR.  This patch fixes the defect in this case
but also preserves the simpler, two TCG operation implementation
when the target is not once of the two sources.

Signed-off-by: Tom Musta <address@hidden>
---
 target-ppc/translate.c |   41 +++++++++++++++++++++++++++++++++--------
 1 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index c5c1108..ffa470f 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -7162,16 +7162,41 @@ static void gen_xxpermdi(DisasContext *ctx)
         gen_exception(ctx, POWERPC_EXCP_VSXU);
         return;
     }
+ 
+    if (unlikely((xT(ctx->opcode) == xA(ctx->opcode)) ||
+                 (xT(ctx->opcode) == xB(ctx->opcode)))) {
+        TCGv_i64 xh, xl;
+ 
+        xh = tcg_temp_new_i64();
+        xl = tcg_temp_new_i64();
+
+        if ((DM(ctx->opcode) & 2) == 0) {
+            tcg_gen_mov_i64(xh, cpu_vsrh(xA(ctx->opcode)));
+        } else {
+            tcg_gen_mov_i64(xh, cpu_vsrl(xA(ctx->opcode)));
+        }
+        if ((DM(ctx->opcode) & 1) == 0) {
+            tcg_gen_mov_i64(xl, cpu_vsrh(xB(ctx->opcode)));
+        } else {
+            tcg_gen_mov_i64(xl, cpu_vsrl(xB(ctx->opcode)));
+        }
 
-    if ((DM(ctx->opcode) & 2) == 0) {
-        tcg_gen_mov_i64(cpu_vsrh(xT(ctx->opcode)), cpu_vsrh(xA(ctx->opcode)));
-    } else {
-        tcg_gen_mov_i64(cpu_vsrh(xT(ctx->opcode)), cpu_vsrl(xA(ctx->opcode)));
-    }
-    if ((DM(ctx->opcode) & 1) == 0) {
-        tcg_gen_mov_i64(cpu_vsrl(xT(ctx->opcode)), cpu_vsrh(xB(ctx->opcode)));
+        tcg_gen_mov_i64(cpu_vsrh(xT(ctx->opcode)), xh);
+        tcg_gen_mov_i64(cpu_vsrl(xT(ctx->opcode)), xl);
+
+        tcg_temp_free_i64(xh);
+        tcg_temp_free_i64(xl);
     } else {
-        tcg_gen_mov_i64(cpu_vsrl(xT(ctx->opcode)), cpu_vsrl(xB(ctx->opcode)));
+        if ((DM(ctx->opcode) & 2) == 0) {
+            tcg_gen_mov_i64(cpu_vsrh(xT(ctx->opcode)), 
cpu_vsrh(xA(ctx->opcode)));
+        } else {
+            tcg_gen_mov_i64(cpu_vsrh(xT(ctx->opcode)), 
cpu_vsrl(xA(ctx->opcode)));
+        }
+        if ((DM(ctx->opcode) & 1) == 0) {
+            tcg_gen_mov_i64(cpu_vsrl(xT(ctx->opcode)), 
cpu_vsrh(xB(ctx->opcode)));
+        } else {
+            tcg_gen_mov_i64(cpu_vsrl(xT(ctx->opcode)), 
cpu_vsrl(xB(ctx->opcode)));
+        }
     }
 }
 
-- 
1.7.1