Workaround ARMv7 emulation issues.

This patch is used to disable the code generator's liveness analysis pass when we
emulate an ARMv7 CPU. This is required to properly run the dex preoptimization pass
during the build of -user system images.

Also includes:
- a fix for a sad typo in target-arm/translate.c related to NEON instruction emulation
- upstream improvements to the x86 and x86_64 backends to generate better goto branches at runtime
- upstream fixes for 64-bit swap and shift operations in TCG

After this patch is applied, re-enabling the ARMv7 memcpy should allow to run the dex preopt
pass succesfully. Anything else is untested though. WE STILL NEED TO FIX THE CODE GENERATOR.

1 files changed, 34 insertions, 14 deletions

diff --git a/tcg/x86_64/tcg-target.c b/tcg/x86_64/tcg-target.c
index 5378e85..a26e714 100644
--- a/tcg/x86_64/tcg-target.c
+++ b/tcg/x86_64/tcg-target.c
@@ -363,6 +363,20 @@ static inline void tcg_out_movi(TCGContext *s, TCGType type,
     }
 }
 
+static void tcg_out_goto(TCGContext *s, int call, uint8_t *target)
+{
+    int32_t disp;
+
+    disp = target - s->code_ptr - 5;
+    if (disp == (target - s->code_ptr - 5)) {
+        tcg_out8(s, call ? 0xe8 : 0xe9);
+        tcg_out32(s, disp);
+    } else {
+        tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_R10, (tcg_target_long) target);
+        tcg_out_modrm(s, 0xff, call ? 2 : 4, TCG_REG_R10);
+    }
+}
+
 static inline void tcg_out_ld(TCGContext *s, TCGType type, int ret,
                               int arg1, tcg_target_long arg2)
 {
@@ -383,7 +397,13 @@ static inline void tcg_out_st(TCGContext *s, TCGType type, int arg,
 
 static inline void tgen_arithi32(TCGContext *s, int c, int r0, int32_t val)
 {
-    if (val == (int8_t)val) {
+    if ((c == ARITH_ADD && val == 1) || (c == ARITH_SUB && val == -1)) {
+        /* inc */
+        tcg_out_modrm(s, 0xff, 0, r0);
+    } else if ((c == ARITH_ADD && val == -1) || (c == ARITH_SUB && val == 1)) {
+        /* dec */
+        tcg_out_modrm(s, 0xff, 1, r0);
+    } else if (val == (int8_t)val) {
         tcg_out_modrm(s, 0x83, c, r0);
         tcg_out8(s, val);
     } else if (c == ARITH_AND && val == 0xffu) {
@@ -400,7 +420,13 @@ static inline void tgen_arithi32(TCGContext *s, int c, int r0, int32_t val)
 
 static inline void tgen_arithi64(TCGContext *s, int c, int r0, int64_t val)
 {
-    if (val == (int8_t)val) {
+    if ((c == ARITH_ADD && val == 1) || (c == ARITH_SUB && val == -1)) {
+        /* inc */
+        tcg_out_modrm(s, 0xff | P_REXW, 0, r0);
+    } else if ((c == ARITH_ADD && val == -1) || (c == ARITH_SUB && val == 1)) {
+        /* dec */
+        tcg_out_modrm(s, 0xff | P_REXW, 1, r0);
+    } else if (val == (int8_t)val) {
         tcg_out_modrm(s, 0x83 | P_REXW, c, r0);
         tcg_out8(s, val);
     } else if (c == ARITH_AND && val == 0xffu) {
@@ -508,6 +534,7 @@ static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args,
                             int opc)
 {
     int addr_reg, data_reg, r0, r1, mem_index, s_bits, bswap, rexw;
+    int32_t offset;
 #if defined(CONFIG_SOFTMMU)
     uint8_t *label1_ptr, *label2_ptr;
 #endif
@@ -558,9 +585,7 @@ static void tcg_out_qemu_ld(TCGContext *s, const TCGArg *args,
 
     /* XXX: move that code at the end of the TB */
     tcg_out_movi(s, TCG_TYPE_I32, TCG_REG_RSI, mem_index);
-    tcg_out8(s, 0xe8);
-    tcg_out32(s, (tcg_target_long)qemu_ld_helpers[s_bits] - 
-              (tcg_target_long)s->code_ptr - 4);
+    tcg_out_goto(s, 1, qemu_ld_helpers[s_bits]);
 
     switch(opc) {
     case 0 | 4:
@@ -760,9 +785,7 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args,
         break;
     }
     tcg_out_movi(s, TCG_TYPE_I32, TCG_REG_RDX, mem_index);
-    tcg_out8(s, 0xe8);
-    tcg_out32(s, (tcg_target_long)qemu_st_helpers[s_bits] - 
-              (tcg_target_long)s->code_ptr - 4);
+    tcg_out_goto(s, 1, qemu_st_helpers[s_bits]);
 
     /* jmp label2 */
     tcg_out8(s, 0xeb);
@@ -839,8 +862,7 @@ static inline void tcg_out_op(TCGContext *s, int opc, const TCGArg *args,
     switch(opc) {
     case INDEX_op_exit_tb:
         tcg_out_movi(s, TCG_TYPE_PTR, TCG_REG_RAX, args[0]);
-        tcg_out8(s, 0xe9); /* jmp tb_ret_addr */
-        tcg_out32(s, tb_ret_addr - s->code_ptr - 4);
+        tcg_out_goto(s, 0, tb_ret_addr);
         break;
     case INDEX_op_goto_tb:
         if (s->tb_jmp_offset) {
@@ -859,16 +881,14 @@ static inline void tcg_out_op(TCGContext *s, int opc, const TCGArg *args,
         break;
     case INDEX_op_call:
         if (const_args[0]) {
-            tcg_out8(s, 0xe8);
-            tcg_out32(s, args[0] - (tcg_target_long)s->code_ptr - 4);
+            tcg_out_goto(s, 1, (void *) args[0]);
         } else {
             tcg_out_modrm(s, 0xff, 2, args[0]);
         }
         break;
     case INDEX_op_jmp:
         if (const_args[0]) {
-            tcg_out8(s, 0xe9);
-            tcg_out32(s, args[0] - (tcg_target_long)s->code_ptr - 4);
+            tcg_out_goto(s, 0, (void *) args[0]);
         } else {
             tcg_out_modrm(s, 0xff, 4, args[0]);
         }