Merge remote-tracking branch 'origin/master' into staging

* origin/master:
  tcg/i386: fix build with -march < i686
  tcg: Streamline movcond_i64 using movcond_i32
  tcg: Streamline movcond_i64 using 32-bit arithmetic
  tcg: Sanity check goto_tb input
  tcg: Sanity check deposit inputs
  tcg: Add tcg_debug_assert
  tcg: Implement concat*_i64 with deposit_i64
  tcg: Emit XORI as NOT for appropriate constants
  tcg: Optimize initial inputs for ori_i64
  tcg: Emit ANDI as EXTU for appropriate constants
  tcg: Adjust descriptions of *cond opcodes
  tcg/mips: fix MIPS32(R2) detection

7 files changed, 188 insertions, 66 deletions

diff --git a/tcg/README b/tcg/README
index 33783ee17b..27846f1ea4 100644
--- a/tcg/README
+++ b/tcg/README
@@ -141,7 +141,7 @@ Define label 'label' at the current program point.
 
 Jump to label.
 
-* brcond_i32/i64 cond, t0, t1, label
+* brcond_i32/i64 t0, t1, cond, label
 
 Conditional jump if t0 cond t1 is true. cond can be:
     TCG_COND_EQ
@@ -301,13 +301,13 @@ This operation would be equivalent to
 
 ********* Conditional moves
 
-* setcond_i32/i64 cond, dest, t1, t2
+* setcond_i32/i64 dest, t1, t2, cond
 
 dest = (t1 cond t2)
 
 Set DEST to 1 if (T1 cond T2) is true, otherwise set to 0.
 
-* movcond_i32/i64 cond, dest, c1, c2, v1, v2
+* movcond_i32/i64 dest, c1, c2, v1, v2, cond
 
 dest = (c1 cond c2 ? v1 : v2)
 
@@ -360,7 +360,7 @@ The following opcodes are internal to TCG.  Thus they are to be implemented by
 32-bit host code generators, but are not to be emitted by guest translators.
 They are emitted as needed by inline functions within "tcg-op.h".
 
-* brcond2_i32 cond, t0_low, t0_high, t1_low, t1_high, label
+* brcond2_i32 t0_low, t0_high, t1_low, t1_high, cond, label
 
 Similar to brcond, except that the 64-bit values T0 and T1
 are formed from two 32-bit arguments.
@@ -377,7 +377,7 @@ is returned in two 32-bit outputs.
 Similar to mul, except two 32-bit (unsigned) inputs T1 and T2 yielding
 the full 64-bit product T0.  The later is returned in two 32-bit outputs.
 
-* setcond2_i32 cond, dest, t1_low, t1_high, t2_low, t2_high
+* setcond2_i32 dest, t1_low, t1_high, t2_low, t2_high, cond
 
 Similar to setcond, except that the 64-bit values T1 and T2 are
 formed from two 32-bit arguments.  The result is a 32-bit value.
diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c
index 122d63630c..0e218c8614 100644
--- a/tcg/i386/tcg-target.c
+++ b/tcg/i386/tcg-target.c
@@ -1893,7 +1893,9 @@ static const TCGTargetOpDef x86_op_defs[] = {
     { INDEX_op_setcond_i32, { "q", "r", "ri" } },
 
     { INDEX_op_deposit_i32, { "Q", "0", "Q" } },
+#if TCG_TARGET_HAS_movcond_i32
     { INDEX_op_movcond_i32, { "r", "r", "ri", "r", "0" } },
+#endif
 
 #if TCG_TARGET_REG_BITS == 32
     { INDEX_op_mulu2_i32, { "a", "d", "a", "r" } },
diff --git a/tcg/mips/tcg-target.c b/tcg/mips/tcg-target.c
index f70910a90f..34e3e7f823 100644
--- a/tcg/mips/tcg-target.c
+++ b/tcg/mips/tcg-target.c
@@ -419,7 +419,7 @@ static inline void tcg_out_movi(TCGContext *s, TCGType type,
 
 static inline void tcg_out_bswap16(TCGContext *s, TCGReg ret, TCGReg arg)
 {
-#ifdef _MIPS_ARCH_MIPS32R2
+#if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
     tcg_out_opc_reg(s, OPC_WSBH, ret, 0, arg);
 #else
     /* ret and arg can't be register at */
@@ -436,7 +436,7 @@ static inline void tcg_out_bswap16(TCGContext *s, TCGReg ret, TCGReg arg)
 
 static inline void tcg_out_bswap16s(TCGContext *s, TCGReg ret, TCGReg arg)
 {
-#ifdef _MIPS_ARCH_MIPS32R2
+#if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
     tcg_out_opc_reg(s, OPC_WSBH, ret, 0, arg);
     tcg_out_opc_reg(s, OPC_SEH, ret, 0, ret);
 #else
@@ -454,7 +454,7 @@ static inline void tcg_out_bswap16s(TCGContext *s, TCGReg ret, TCGReg arg)
 
 static inline void tcg_out_bswap32(TCGContext *s, TCGReg ret, TCGReg arg)
 {
-#ifdef _MIPS_ARCH_MIPS32R2
+#if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
     tcg_out_opc_reg(s, OPC_WSBH, ret, 0, arg);
     tcg_out_opc_sa(s, OPC_ROTR, ret, ret, 16);
 #else
@@ -480,7 +480,7 @@ static inline void tcg_out_bswap32(TCGContext *s, TCGReg ret, TCGReg arg)
 
 static inline void tcg_out_ext8s(TCGContext *s, TCGReg ret, TCGReg arg)
 {
-#ifdef _MIPS_ARCH_MIPS32R2
+#if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
     tcg_out_opc_reg(s, OPC_SEB, ret, 0, arg);
 #else
     tcg_out_opc_sa(s, OPC_SLL, ret, arg, 24);
@@ -490,7 +490,7 @@ static inline void tcg_out_ext8s(TCGContext *s, TCGReg ret, TCGReg arg)
 
 static inline void tcg_out_ext16s(TCGContext *s, TCGReg ret, TCGReg arg)
 {
-#ifdef _MIPS_ARCH_MIPS32R2
+#if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
     tcg_out_opc_reg(s, OPC_SEH, ret, 0, arg);
 #else
     tcg_out_opc_sa(s, OPC_SLL, ret, arg, 16);
diff --git a/tcg/mips/tcg-target.h b/tcg/mips/tcg-target.h
index d147e70eb1..7020d65845 100644
--- a/tcg/mips/tcg-target.h
+++ b/tcg/mips/tcg-target.h
@@ -88,16 +88,16 @@ typedef enum {
 #define TCG_TARGET_HAS_nand_i32         0
 
 /* optional instructions only implemented on MIPS4, MIPS32 and Loongson 2 */
-#if defined(_MIPS_ARCH_MIPS4) || defined(_MIPS_ARCH_MIPS32) || \
-    defined(_MIPS_ARCH_MIPS32R2) || defined(_MIPS_ARCH_LOONGSON2E) || \
-    defined(_MIPS_ARCH_LOONGSON2F)
+#if (defined(__mips_isa_rev) && (__mips_isa_rev >= 1)) || \
+    defined(_MIPS_ARCH_LOONGSON2E) || defined(_MIPS_ARCH_LOONGSON2F) || \
+    defined(_MIPS_ARCH_MIPS4)
 #define TCG_TARGET_HAS_movcond_i32      1
 #else
 #define TCG_TARGET_HAS_movcond_i32      0
 #endif
 
 /* optional instructions only implemented on MIPS32R2 */
-#ifdef _MIPS_ARCH_MIPS32R2
+#if defined(__mips_isa_rev) && (__mips_isa_rev >= 2)
 #define TCG_TARGET_HAS_bswap16_i32      1
 #define TCG_TARGET_HAS_bswap32_i32      1
 #define TCG_TARGET_HAS_rot_i32          1
diff --git a/tcg/tcg-op.h b/tcg/tcg-op.h
index 6d28f82ad8..bd93fe4f03 100644
--- a/tcg/tcg-op.h
+++ b/tcg/tcg-op.h
@@ -518,18 +518,34 @@ static inline void tcg_gen_and_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
     }
 }
 
-static inline void tcg_gen_andi_i32(TCGv_i32 ret, TCGv_i32 arg1, int32_t arg2)
+static inline void tcg_gen_andi_i32(TCGv_i32 ret, TCGv_i32 arg1, uint32_t arg2)
 {
-    /* some cases can be optimized here */
-    if (arg2 == 0) {
+    TCGv_i32 t0;
+    /* Some cases can be optimized here.  */
+    switch (arg2) {
+    case 0:
         tcg_gen_movi_i32(ret, 0);
-    } else if (arg2 == 0xffffffff) {
+        return;
+    case 0xffffffffu:
         tcg_gen_mov_i32(ret, arg1);
-    } else {
-        TCGv_i32 t0 = tcg_const_i32(arg2);
-        tcg_gen_and_i32(ret, arg1, t0);
-        tcg_temp_free_i32(t0);
-    }
+        return;
+    case 0xffu:
+        /* Don't recurse with tcg_gen_ext8u_i32.  */
+        if (TCG_TARGET_HAS_ext8u_i32) {
+            tcg_gen_op2_i32(INDEX_op_ext8u_i32, ret, arg1);
+            return;
+        }
+        break;
+    case 0xffffu:
+        if (TCG_TARGET_HAS_ext16u_i32) {
+            tcg_gen_op2_i32(INDEX_op_ext16u_i32, ret, arg1);
+            return;
+        }
+        break;
+    }
+    t0 = tcg_const_i32(arg2);
+    tcg_gen_and_i32(ret, arg1, t0);
+    tcg_temp_free_i32(t0);
 }
 
 static inline void tcg_gen_or_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
@@ -543,9 +559,9 @@ static inline void tcg_gen_or_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 
 static inline void tcg_gen_ori_i32(TCGv_i32 ret, TCGv_i32 arg1, int32_t arg2)
 {
-    /* some cases can be optimized here */
-    if (arg2 == 0xffffffff) {
-        tcg_gen_movi_i32(ret, 0xffffffff);
+    /* Some cases can be optimized here.  */
+    if (arg2 == -1) {
+        tcg_gen_movi_i32(ret, -1);
     } else if (arg2 == 0) {
         tcg_gen_mov_i32(ret, arg1);
     } else {
@@ -566,9 +582,12 @@ static inline void tcg_gen_xor_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 
 static inline void tcg_gen_xori_i32(TCGv_i32 ret, TCGv_i32 arg1, int32_t arg2)
 {
-    /* some cases can be optimized here */
+    /* Some cases can be optimized here.  */
     if (arg2 == 0) {
         tcg_gen_mov_i32(ret, arg1);
+    } else if (arg2 == -1 && TCG_TARGET_HAS_not_i32) {
+        /* Don't recurse with tcg_gen_not_i32.  */
+        tcg_gen_op2_i32(INDEX_op_not_i32, ret, arg1);
     } else {
         TCGv_i32 t0 = tcg_const_i32(arg2);
         tcg_gen_xor_i32(ret, arg1, t0);
@@ -1120,9 +1139,38 @@ static inline void tcg_gen_and_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
     }
 }
 
-static inline void tcg_gen_andi_i64(TCGv_i64 ret, TCGv_i64 arg1, int64_t arg2)
+static inline void tcg_gen_andi_i64(TCGv_i64 ret, TCGv_i64 arg1, uint64_t arg2)
 {
-    TCGv_i64 t0 = tcg_const_i64(arg2);
+    TCGv_i64 t0;
+    /* Some cases can be optimized here.  */
+    switch (arg2) {
+    case 0:
+        tcg_gen_movi_i64(ret, 0);
+        return;
+    case 0xffffffffffffffffull:
+        tcg_gen_mov_i64(ret, arg1);
+        return;
+    case 0xffull:
+        /* Don't recurse with tcg_gen_ext8u_i32.  */
+        if (TCG_TARGET_HAS_ext8u_i64) {
+            tcg_gen_op2_i64(INDEX_op_ext8u_i64, ret, arg1);
+            return;
+        }
+        break;
+    case 0xffffu:
+        if (TCG_TARGET_HAS_ext16u_i64) {
+            tcg_gen_op2_i64(INDEX_op_ext16u_i64, ret, arg1);
+            return;
+        }
+        break;
+    case 0xffffffffull:
+        if (TCG_TARGET_HAS_ext32u_i64) {
+            tcg_gen_op2_i64(INDEX_op_ext32u_i64, ret, arg1);
+            return;
+        }
+        break;
+    }
+    t0 = tcg_const_i64(arg2);
     tcg_gen_and_i64(ret, arg1, t0);
     tcg_temp_free_i64(t0);
 }
@@ -1138,9 +1186,16 @@ static inline void tcg_gen_or_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 
 static inline void tcg_gen_ori_i64(TCGv_i64 ret, TCGv_i64 arg1, int64_t arg2)
 {
-    TCGv_i64 t0 = tcg_const_i64(arg2);
-    tcg_gen_or_i64(ret, arg1, t0);
-    tcg_temp_free_i64(t0);
+    /* Some cases can be optimized here.  */
+    if (arg2 == -1) {
+        tcg_gen_movi_i64(ret, -1);
+    } else if (arg2 == 0) {
+        tcg_gen_mov_i64(ret, arg1);
+    } else {
+        TCGv_i64 t0 = tcg_const_i64(arg2);
+        tcg_gen_or_i64(ret, arg1, t0);
+        tcg_temp_free_i64(t0);
+    }
 }
 
 static inline void tcg_gen_xor_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
@@ -1154,9 +1209,17 @@ static inline void tcg_gen_xor_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
 
 static inline void tcg_gen_xori_i64(TCGv_i64 ret, TCGv_i64 arg1, int64_t arg2)
 {
-    TCGv_i64 t0 = tcg_const_i64(arg2);
-    tcg_gen_xor_i64(ret, arg1, t0);
-    tcg_temp_free_i64(t0);
+    /* Some cases can be optimized here.  */
+    if (arg2 == 0) {
+        tcg_gen_mov_i64(ret, arg1);
+    } else if (arg2 == -1 && TCG_TARGET_HAS_not_i64) {
+        /* Don't recurse with tcg_gen_not_i64.  */
+        tcg_gen_op2_i64(INDEX_op_not_i64, ret, arg1);
+    } else {
+        TCGv_i64 t0 = tcg_const_i64(arg2);
+        tcg_gen_xor_i64(ret, arg1, t0);
+        tcg_temp_free_i64(t0);
+    }
 }
 
 static inline void tcg_gen_shl_i64(TCGv_i64 ret, TCGv_i64 arg1, TCGv_i64 arg2)
@@ -1746,36 +1809,6 @@ static inline void tcg_gen_discard_i64(TCGv_i64 arg)
 #endif
 }
 
-static inline void tcg_gen_concat_i32_i64(TCGv_i64 dest, TCGv_i32 low, TCGv_i32 high)
-{
-#if TCG_TARGET_REG_BITS == 32
-    tcg_gen_mov_i32(TCGV_LOW(dest), low);
-    tcg_gen_mov_i32(TCGV_HIGH(dest), high);
-#else
-    TCGv_i64 tmp = tcg_temp_new_i64();
-    /* This extension is only needed for type correctness.
-       We may be able to do better given target specific information.  */
-    tcg_gen_extu_i32_i64(tmp, high);
-    tcg_gen_shli_i64(tmp, tmp, 32);
-    tcg_gen_extu_i32_i64(dest, low);
-    tcg_gen_or_i64(dest, dest, tmp);
-    tcg_temp_free_i64(tmp);
-#endif
-}
-
-static inline void tcg_gen_concat32_i64(TCGv_i64 dest, TCGv_i64 low, TCGv_i64 high)
-{
-#if TCG_TARGET_REG_BITS == 32
-    tcg_gen_concat_i32_i64(dest, TCGV_LOW(low), TCGV_LOW(high));
-#else
-    TCGv_i64 tmp = tcg_temp_new_i64();
-    tcg_gen_ext32u_i64(dest, low);
-    tcg_gen_shli_i64(tmp, high, 32);
-    tcg_gen_or_i64(dest, dest, tmp);
-    tcg_temp_free_i64(tmp);
-#endif
-}
-
 static inline void tcg_gen_andc_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
 {
     if (TCG_TARGET_HAS_andc_i32) {
@@ -2048,6 +2081,10 @@ static inline void tcg_gen_deposit_i32(TCGv_i32 ret, TCGv_i32 arg1,
     uint32_t mask;
     TCGv_i32 t1;
 
+    tcg_debug_assert(ofs < 32);
+    tcg_debug_assert(len <= 32);
+    tcg_debug_assert(ofs + len <= 32);
+
     if (ofs == 0 && len == 32) {
         tcg_gen_mov_i32(ret, arg2);
         return;
@@ -2079,6 +2116,10 @@ static inline void tcg_gen_deposit_i64(TCGv_i64 ret, TCGv_i64 arg1,
     uint64_t mask;
     TCGv_i64 t1;
 
+    tcg_debug_assert(ofs < 64);
+    tcg_debug_assert(len <= 64);
+    tcg_debug_assert(ofs + len <= 64);
+
     if (ofs == 0 && len == 64) {
         tcg_gen_mov_i64(ret, arg2);
         return;
@@ -2118,6 +2159,36 @@ static inline void tcg_gen_deposit_i64(TCGv_i64 ret, TCGv_i64 arg1,
     tcg_temp_free_i64(t1);
 }
 
+static inline void tcg_gen_concat_i32_i64(TCGv_i64 dest, TCGv_i32 low,
+                                          TCGv_i32 high)
+{
+#if TCG_TARGET_REG_BITS == 32
+    tcg_gen_mov_i32(TCGV_LOW(dest), low);
+    tcg_gen_mov_i32(TCGV_HIGH(dest), high);
+#else
+    TCGv_i64 tmp = tcg_temp_new_i64();
+    /* These extensions are only needed for type correctness.
+       We may be able to do better given target specific information.  */
+    tcg_gen_extu_i32_i64(tmp, high);
+    tcg_gen_extu_i32_i64(dest, low);
+    /* If deposit is available, use it.  Otherwise use the extra
+       knowledge that we have of the zero-extensions above.  */
+    if (TCG_TARGET_HAS_deposit_i64 && TCG_TARGET_deposit_i64_valid(32, 32)) {
+        tcg_gen_deposit_i64(dest, dest, tmp, 32, 32);
+    } else {
+        tcg_gen_shli_i64(tmp, tmp, 32);
+        tcg_gen_or_i64(dest, dest, tmp);
+    }
+    tcg_temp_free_i64(tmp);
+#endif
+}
+
+static inline void tcg_gen_concat32_i64(TCGv_i64 dest, TCGv_i64 low,
+                                        TCGv_i64 high)
+{
+    tcg_gen_deposit_i64(dest, low, high, 32, 32);
+}
+
 static inline void tcg_gen_movcond_i32(TCGCond cond, TCGv_i32 ret,
                                        TCGv_i32 c1, TCGv_i32 c2,
                                        TCGv_i32 v1, TCGv_i32 v2)
@@ -2141,6 +2212,33 @@ static inline void tcg_gen_movcond_i64(TCGCond cond, TCGv_i64 ret,
                                        TCGv_i64 c1, TCGv_i64 c2,
                                        TCGv_i64 v1, TCGv_i64 v2)
 {
+#if TCG_TARGET_REG_BITS == 32
+    TCGv_i32 t0 = tcg_temp_new_i32();
+    TCGv_i32 t1 = tcg_temp_new_i32();
+    tcg_gen_op6i_i32(INDEX_op_setcond2_i32, t0,
+                     TCGV_LOW(c1), TCGV_HIGH(c1),
+                     TCGV_LOW(c2), TCGV_HIGH(c2), cond);
+
+    if (TCG_TARGET_HAS_movcond_i32) {
+        tcg_gen_movi_i32(t1, 0);
+        tcg_gen_movcond_i32(TCG_COND_NE, TCGV_LOW(ret), t0, t1,
+                            TCGV_LOW(v1), TCGV_LOW(v2));
+        tcg_gen_movcond_i32(TCG_COND_NE, TCGV_HIGH(ret), t0, t1,
+                            TCGV_HIGH(v1), TCGV_HIGH(v2));
+    } else {
+        tcg_gen_neg_i32(t0, t0);
+
+        tcg_gen_and_i32(t1, TCGV_LOW(v1), t0);
+        tcg_gen_andc_i32(TCGV_LOW(ret), TCGV_LOW(v2), t0);
+        tcg_gen_or_i32(TCGV_LOW(ret), TCGV_LOW(ret), t1);
+
+        tcg_gen_and_i32(t1, TCGV_HIGH(v1), t0);
+        tcg_gen_andc_i32(TCGV_HIGH(ret), TCGV_HIGH(v2), t0);
+        tcg_gen_or_i32(TCGV_HIGH(ret), TCGV_HIGH(ret), t1);
+    }
+    tcg_temp_free_i32(t0);
+    tcg_temp_free_i32(t1);
+#else
     if (TCG_TARGET_HAS_movcond_i64) {
         tcg_gen_op6i_i64(INDEX_op_movcond_i64, ret, c1, c2, v1, v2, cond);
     } else {
@@ -2154,6 +2252,7 @@ static inline void tcg_gen_movcond_i64(TCGCond cond, TCGv_i64 ret,
         tcg_temp_free_i64(t0);
         tcg_temp_free_i64(t1);
     }
+#endif
 }
 
 /***************************************/
@@ -2204,8 +2303,15 @@ static inline void tcg_gen_exit_tb(tcg_target_long val)
     tcg_gen_op1i(INDEX_op_exit_tb, val);
 }
 
-static inline void tcg_gen_goto_tb(int idx)
+static inline void tcg_gen_goto_tb(unsigned idx)
 {
+    /* We only support two chained exits.  */
+    tcg_debug_assert(idx <= 1);
+#ifdef CONFIG_DEBUG_TCG
+    /* Verify that we havn't seen this numbered exit before.  */
+    tcg_debug_assert((tcg_ctx.goto_tb_issue_mask & (1 << idx)) == 0);
+    tcg_ctx.goto_tb_issue_mask |= 1 << idx;
+#endif
     tcg_gen_op1i(INDEX_op_goto_tb, idx);
 }
 
diff --git a/tcg/tcg.c b/tcg/tcg.c
index b3c265013d..c069e44a0e 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -298,6 +298,10 @@ void tcg_func_start(TCGContext *s)
     s->nb_labels = 0;
     s->current_frame_offset = s->frame_start;
 
+#ifdef CONFIG_DEBUG_TCG
+    s->goto_tb_issue_mask = 0;
+#endif
+
     gen_opc_ptr = gen_opc_buf;
     gen_opparam_ptr = gen_opparam_buf;
 }
diff --git a/tcg/tcg.h b/tcg/tcg.h
index 48a56f0b15..af7464a650 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -390,6 +390,7 @@ struct TCGContext {
 
 #ifdef CONFIG_DEBUG_TCG
     int temps_in_use;
+    int goto_tb_issue_mask;
 #endif
 };
 
@@ -530,6 +531,15 @@ do {\
     abort();\
 } while (0)
 
+#ifdef CONFIG_DEBUG_TCG
+# define tcg_debug_assert(X) do { assert(X); } while (0)
+#elif QEMU_GNUC_PREREQ(4, 5)
+# define tcg_debug_assert(X) \
+    do { if (!(X)) { __builtin_unreachable(); } } while (0)
+#else
+# define tcg_debug_assert(X) do { (void)(X); } while (0)
+#endif
+
 void tcg_add_target_add_op_defs(const TCGTargetOpDef *tdefs);
 
 #if TCG_TARGET_REG_BITS == 32