[Qemu-devel] [PATCH v3 09/10] target/ppc: add ov32 flag in divide operations

[Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>]

Add helper_div_compute_ov() in the int_helper for updating the overflow
flags.

For Divide Word:
SO, OV, and OV32 bits reflects overflow of the 32-bit result

For Divide DoubleWord:
SO, OV, and OV32 bits reflects overflow of the 64-bit result

Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
---
 target/ppc/int_helper.c | 53 +++++++++++++++++++------------------------------
 target/ppc/translate.c  | 10 ++++++++--
 2 files changed, 28 insertions(+), 35 deletions(-)

diff --git a/target/ppc/int_helper.c b/target/ppc/int_helper.c
index dd0a892..1cad62f 100644
--- a/target/ppc/int_helper.c
+++ b/target/ppc/int_helper.c
@@ -28,6 +28,22 @@
 /*****************************************************************************/
 /* Fixed point operations helpers */
 
+static inline void helper_div_compute_ov(CPUPPCState *env, uint32_t oe,
+                                         int overflow)
+{
+    if (oe) {
+        if (unlikely(overflow)) {
+            env->so = env->ov = 1;
+        } else {
+            env->ov = 0;
+        }
+
+        if (is_isa300(env)) {
+            env->ov32 = env->ov;
+        }
+    }
+}
+
 target_ulong helper_divweu(CPUPPCState *env, target_ulong ra, target_ulong rb,
                            uint32_t oe)
 {
@@ -48,14 +64,7 @@ target_ulong helper_divweu(CPUPPCState *env, target_ulong ra, target_ulong rb,
         rt = 0; /* Undefined */
     }
 
-    if (oe) {
-        if (unlikely(overflow)) {
-            env->so = env->ov = 1;
-        } else {
-            env->ov = 0;
-        }
-    }
-
+    helper_div_compute_ov(env, oe, overflow);
     return (target_ulong)rt;
 }
 
@@ -80,14 +89,7 @@ target_ulong helper_divwe(CPUPPCState *env, target_ulong ra, target_ulong rb,
         rt = 0; /* Undefined */
     }
 
-    if (oe) {
-        if (unlikely(overflow)) {
-            env->so = env->ov = 1;
-        } else {
-            env->ov = 0;
-        }
-    }
-
+    helper_div_compute_ov(env, oe, overflow);
     return (target_ulong)rt;
 }
 
@@ -104,14 +106,7 @@ uint64_t helper_divdeu(CPUPPCState *env, uint64_t ra, uint64_t rb, uint32_t oe)
         rt = 0; /* Undefined */
     }
 
-    if (oe) {
-        if (unlikely(overflow)) {
-            env->so = env->ov = 1;
-        } else {
-            env->ov = 0;
-        }
-    }
-
+    helper_div_compute_ov(env, oe, overflow);
     return rt;
 }
 
@@ -126,15 +121,7 @@ uint64_t helper_divde(CPUPPCState *env, uint64_t rau, uint64_t rbu, uint32_t oe)
         rt = 0; /* Undefined */
     }
 
-    if (oe) {
-
-        if (unlikely(overflow)) {
-            env->so = env->ov = 1;
-        } else {
-            env->ov = 0;
-        }
-    }
-
+    helper_div_compute_ov(env, oe, overflow);
     return rt;
 }
 
diff --git a/target/ppc/translate.c b/target/ppc/translate.c
index ba3387e..99dfcf7 100644
--- a/target/ppc/translate.c
+++ b/target/ppc/translate.c
@@ -1024,6 +1024,9 @@ static inline void gen_op_arith_divw(DisasContext *ctx, TCGv ret, TCGv arg1,
     }
     if (compute_ov) {
         tcg_gen_extu_i32_tl(cpu_ov, t2);
+        if (is_isa300(ctx)) {
+            tcg_gen_extu_i32_tl(cpu_ov32, t2);
+        }
         tcg_gen_or_tl(cpu_so, cpu_so, cpu_ov);
     }
     tcg_temp_free_i32(t0);
@@ -1095,6 +1098,9 @@ static inline void gen_op_arith_divd(DisasContext *ctx, TCGv ret, TCGv arg1,
     }
     if (compute_ov) {
         tcg_gen_mov_tl(cpu_ov, t2);
+        if (is_isa300(ctx)) {
+            tcg_gen_mov_tl(cpu_ov32, t2);
+        }
         tcg_gen_or_tl(cpu_so, cpu_so, cpu_ov);
     }
     tcg_temp_free_i64(t0);
@@ -1113,10 +1119,10 @@ static void glue(gen_, name)(DisasContext *ctx)
                       cpu_gpr[rA(ctx->opcode)], cpu_gpr[rB(ctx->opcode)],     \
                       sign, compute_ov);                                      \
 }
-/* divwu  divwu.  divwuo  divwuo.   */
+/* divdu  divdu.  divduo  divduo.   */
 GEN_INT_ARITH_DIVD(divdu, 0x0E, 0, 0);
 GEN_INT_ARITH_DIVD(divduo, 0x1E, 0, 1);
-/* divw  divw.  divwo  divwo.   */
+/* divd  divd.  divdo  divdo.   */
 GEN_INT_ARITH_DIVD(divd, 0x0F, 1, 0);
 GEN_INT_ARITH_DIVD(divdo, 0x1F, 1, 1);
 
-- 
2.7.4