[v2,07/13] tcg/i386: implement goto_ptr op

Commit Message

Emilio Cota April 25, 2017, 7:53 a.m. UTC

Signed-off-by: Emilio G. Cota <[e-mail]>
---
 tcg/i386/tcg-target.h     |  2 +-
 tcg/i386/tcg-target.inc.c | 13 +++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

Comments

Richard Henderson April 25, 2017, 11:32 a.m. UTC | #1

On 04/25/2017 09:53 AM, Emilio G. Cota wrote:
>   static const TCGTargetOpDef *tcg_target_op_def(TCGOpcode op)
>   {
> +    static const TCGTargetOpDef ri = { .args_ct_str = { "ri" } };
>       static const TCGTargetOpDef ri_r = { .args_ct_str = { "ri", "r" } };
>       static const TCGTargetOpDef re_r = { .args_ct_str = { "re", "r" } };
>       static const TCGTargetOpDef qi_r = { .args_ct_str = { "qi", "r" } };
> @@ -2324,6 +2333,9 @@ static const TCGTargetOpDef *tcg_target_op_def(TCGOpcode op)
>       case INDEX_op_st_i64:
>           return &re_r;
>   
> +    case INDEX_op_goto_ptr:
> +        return &ri;
> +

This is incorrect.  You only handle register inputs (i.e. just "r") in your 
implementation.  Indeed, that's also the only thing that makes sense.


r~

Patch

diff --git a/tcg/i386/tcg-target.h b/tcg/i386/tcg-target.h
index 59d9835..73a15f7 100644
--- a/tcg/i386/tcg-target.h
+++ b/tcg/i386/tcg-target.h
@@ -107,7 +107,7 @@  extern bool have_popcnt;
 #define TCG_TARGET_HAS_muls2_i32        1
 #define TCG_TARGET_HAS_muluh_i32        0
 #define TCG_TARGET_HAS_mulsh_i32        0
-#define TCG_TARGET_HAS_goto_ptr         0
+#define TCG_TARGET_HAS_goto_ptr         1
 
 #if TCG_TARGET_REG_BITS == 64
 #define TCG_TARGET_HAS_extrl_i64_i32    0
diff --git a/tcg/i386/tcg-target.inc.c b/tcg/i386/tcg-target.inc.c
index 5918008..f6fb03e 100644
--- a/tcg/i386/tcg-target.inc.c
+++ b/tcg/i386/tcg-target.inc.c
@@ -1906,6 +1906,14 @@  static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
         }
         s->tb_jmp_reset_offset[a0] = tcg_current_code_size(s);
         break;
+    case INDEX_op_goto_ptr:
+        /* save target address into new register */
+        tcg_out_mov(s, TCG_TYPE_PTR, TCG_REG_EDX, a0);
+        /* set return value to 0 */
+        tgen_arithr(s, ARITH_XOR, TCG_REG_EAX, TCG_REG_EAX);
+        /* jmp to the target address (could be epilogue) */
+        tcg_out_modrm(s, OPC_GRP5, EXT5_JMPN_Ev, TCG_REG_EDX);
+        break;
     case INDEX_op_br:
         tcg_out_jxx(s, JCC_JMP, arg_label(a0), 0);
         break;
@@ -2277,6 +2285,7 @@  static inline void tcg_out_op(TCGContext *s, TCGOpcode opc,
 
 static const TCGTargetOpDef *tcg_target_op_def(TCGOpcode op)
 {
+    static const TCGTargetOpDef ri = { .args_ct_str = { "ri" } };
     static const TCGTargetOpDef ri_r = { .args_ct_str = { "ri", "r" } };
     static const TCGTargetOpDef re_r = { .args_ct_str = { "re", "r" } };
     static const TCGTargetOpDef qi_r = { .args_ct_str = { "qi", "r" } };
@@ -2324,6 +2333,9 @@  static const TCGTargetOpDef *tcg_target_op_def(TCGOpcode op)
     case INDEX_op_st_i64:
         return &re_r;
 
+    case INDEX_op_goto_ptr:
+        return &ri;
+
     case INDEX_op_add_i32:
     case INDEX_op_add_i64:
         return &r_r_re;
@@ -2569,6 +2581,7 @@  static void tcg_target_qemu_prologue(TCGContext *s)
 
     /* TB epilogue */
     tb_ret_addr = s->code_ptr;
+    s->code_gen_epilogue = s->code_ptr;
 
     tcg_out_addi(s, TCG_REG_CALL_STACK, stack_addend);