target/arm: Factor out 'generate singlestep exception' function

Factor out code to 'generate a singlestep exception', which is
currently repeated in four places.

To do this we need to also pull the identical copies of the
gen-exception() function out of translate-a64.c and translate.c
into translate.h.

(There is a bug in the code: we're taking the exception to the wrong
target EL.  This will be simpler to fix if there's only one place to
do it.)
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 20190805130952.4415-2-peter.maydell@linaro.org

target/arm/translate-a64.c

@@ -253,19 +253,6 @@ static void gen_exception_internal(int excp)
     tcg_temp_free_i32(tcg_excp);
 }
 
-static void gen_exception(int excp, uint32_t syndrome, uint32_t target_el)
-{
-    TCGv_i32 tcg_excp = tcg_const_i32(excp);
-    TCGv_i32 tcg_syn = tcg_const_i32(syndrome);
-    TCGv_i32 tcg_el = tcg_const_i32(target_el);
-
-    gen_helper_exception_with_syndrome(cpu_env, tcg_excp,
-                                       tcg_syn, tcg_el);
-    tcg_temp_free_i32(tcg_el);
-    tcg_temp_free_i32(tcg_syn);
-    tcg_temp_free_i32(tcg_excp);
-}
-
 static void gen_exception_internal_insn(DisasContext *s, int offset, int excp)
 {
     gen_a64_set_pc_im(s->pc - offset);
@@ -305,8 +292,7 @@ static void gen_step_complete_exception(DisasContext *s)
      * of the exception, and our syndrome information is always correct.
      */
     gen_ss_advance(s);
-    gen_exception(EXCP_UDEF, syn_swstep(s->ss_same_el, 1, s->is_ldex),
-                  default_exception_el(s));
+    gen_swstep_exception(s, 1, s->is_ldex);
     s->base.is_jmp = DISAS_NORETURN;
 }
 
@@ -14261,8 +14247,7 @@ static void aarch64_tr_translate_insn(DisasContextBase *dcbase, CPUState *cpu)
          * bits should be zero.
          */
         assert(dc->base.num_insns == 1);
-        gen_exception(EXCP_UDEF, syn_swstep(dc->ss_same_el, 0, 0),
-                      default_exception_el(dc));
+        gen_swstep_exception(dc, 0, 0);
         dc->base.is_jmp = DISAS_NORETURN;
     } else {
         disas_a64_insn(env, dc);

target/arm/translate.c

@@ -282,20 +282,6 @@ static void gen_exception_internal(int excp)
     tcg_temp_free_i32(tcg_excp);
 }
 
-static void gen_exception(int excp, uint32_t syndrome, uint32_t target_el)
-{
-    TCGv_i32 tcg_excp = tcg_const_i32(excp);
-    TCGv_i32 tcg_syn = tcg_const_i32(syndrome);
-    TCGv_i32 tcg_el = tcg_const_i32(target_el);
-
-    gen_helper_exception_with_syndrome(cpu_env, tcg_excp,
-                                       tcg_syn, tcg_el);
-
-    tcg_temp_free_i32(tcg_el);
-    tcg_temp_free_i32(tcg_syn);
-    tcg_temp_free_i32(tcg_excp);
-}
-
 static void gen_step_complete_exception(DisasContext *s)
 {
     /* We just completed step of an insn. Move from Active-not-pending
@@ -308,8 +294,7 @@ static void gen_step_complete_exception(DisasContext *s)
      * of the exception, and our syndrome information is always correct.
      */
     gen_ss_advance(s);
-    gen_exception(EXCP_UDEF, syn_swstep(s->ss_same_el, 1, s->is_ldex),
-                  default_exception_el(s));
+    gen_swstep_exception(s, 1, s->is_ldex);
     s->base.is_jmp = DISAS_NORETURN;
 }
 
@@ -12024,8 +12009,7 @@ static bool arm_pre_translate_insn(DisasContext *dc)
          * bits should be zero.
          */
         assert(dc->base.num_insns == 1);
-        gen_exception(EXCP_UDEF, syn_swstep(dc->ss_same_el, 0, 0),
-                      default_exception_el(dc));
+        gen_swstep_exception(dc, 0, 0);
         dc->base.is_jmp = DISAS_NORETURN;
         return true;
     }

target/arm/translate.h

@@ -2,6 +2,7 @@
 #define TARGET_ARM_TRANSLATE_H
 
 #include "exec/translator.h"
+#include "internals.h"
 
 
 /* internal defines */
@@ -232,6 +233,28 @@ static inline void gen_ss_advance(DisasContext *s)
     }
 }
 
+static inline void gen_exception(int excp, uint32_t syndrome,
+                                 uint32_t target_el)
+{
+    TCGv_i32 tcg_excp = tcg_const_i32(excp);
+    TCGv_i32 tcg_syn = tcg_const_i32(syndrome);
+    TCGv_i32 tcg_el = tcg_const_i32(target_el);
+
+    gen_helper_exception_with_syndrome(cpu_env, tcg_excp,
+                                       tcg_syn, tcg_el);
+
+    tcg_temp_free_i32(tcg_el);
+    tcg_temp_free_i32(tcg_syn);
+    tcg_temp_free_i32(tcg_excp);
+}
+
+/* Generate an architectural singlestep exception */
+static inline void gen_swstep_exception(DisasContext *s, int isv, int ex)
+{
+    gen_exception(EXCP_UDEF, syn_swstep(s->ss_same_el, isv, ex),
+                  default_exception_el(s));
+}
+
 /*
  * Given a VFP floating point constant encoded into an 8 bit immediate in an
  * instruction, expand it to the actual constant value of the specified