[Qemu-devel] [PATCH 1/2] target-arm: Unify AArch32 exception return generating functions

[Sergey Sorokin]

There is a duplicating code in AArch32 exception return implementation.
The patch rearranges the code to avoid this.

Signed-off-by: Sergey Sorokin <afaral...@yandex.ru>
---
 target-arm/translate.c | 36 +++++++++++++++++++++---------------
 1 file changed, 21 insertions(+), 15 deletions(-)

diff --git a/target-arm/translate.c b/target-arm/translate.c
index 940ec8d..68671b7 100644
--- a/target-arm/translate.c
+++ b/target-arm/translate.c
@@ -4349,24 +4349,27 @@ static void gen_mrs_banked(DisasContext *s, int r, int 
sysm, int rn)
     s->is_jmp = DISAS_UPDATE;
 }
 
-/* Generate an old-style exception return. Marks pc as dead. */
-static void gen_exception_return(DisasContext *s, TCGv_i32 pc)
+/* Generate an exception return. Marks both values as dead. */
+static void gen_exception_return_internal(DisasContext *s, TCGv_i32 pc,
+                                          TCGv_i32 cpsr)
 {
-    TCGv_i32 tmp;
+    gen_helper_cpsr_write_eret(cpu_env, cpsr);
+    tcg_temp_free_i32(cpsr);
     store_reg(s, 15, pc);
-    tmp = load_cpu_field(spsr);
-    gen_helper_cpsr_write_eret(cpu_env, tmp);
-    tcg_temp_free_i32(tmp);
     s->is_jmp = DISAS_JUMP;
 }
 
+/* Generate an old-style exception return. Marks pc as dead. */
+static void gen_exception_return(DisasContext *s, TCGv_i32 pc)
+{
+    TCGv_i32 tmp = load_cpu_field(spsr);
+    gen_exception_return_internal(s, pc, tmp);
+}
+
 /* Generate a v6 exception return.  Marks both values as dead.  */
 static void gen_rfe(DisasContext *s, TCGv_i32 pc, TCGv_i32 cpsr)
 {
-    gen_helper_cpsr_write_eret(cpu_env, cpsr);
-    tcg_temp_free_i32(cpsr);
-    store_reg(s, 15, pc);
-    s->is_jmp = DISAS_JUMP;
+    gen_exception_return_internal(s, pc, cpsr);
 }
 
 static void gen_nop_hint(DisasContext *s, int val)
@@ -9378,11 +9381,14 @@ static void disas_arm_insn(DisasContext *s, unsigned 
int insn)
                     store_reg(s, rn, loaded_var);
                 }
                 if (exc_return) {
-                    /* Restore CPSR from SPSR.  */
-                    tmp = load_cpu_field(spsr);
-                    gen_helper_cpsr_write_eret(cpu_env, tmp);
-                    tcg_temp_free_i32(tmp);
-                    s->is_jmp = DISAS_JUMP;
+                    /* Restore CPSR from SPSR.
+                     * Since gen_exception_return() function updates r15
+                     * we need just pass current r15 value into it.
+                     */
+                    tmp = tcg_temp_new_i32();
+                    tcg_gen_mov_i32(tmp, cpu_R[15]);
+                    /* It marks tmp as dead. */
+                    gen_exception_return(s, tmp);
                 }
             }
             break;
-- 
1.9.3