implement cmpxchg8b, patch by Tom Hughes.
CCMAIL: 69688-done@bugs.kde.org


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@2154 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/vg_helpers.S b/coregrind/vg_helpers.S
index 270caac..ea7614e 100644
--- a/coregrind/vg_helpers.S
+++ b/coregrind/vg_helpers.S
@@ -94,6 +94,7 @@
 	* integer multiplication
         * setting and getting obscure eflags
 	* double-length shifts
+        * eight byte compare and exchange
 	
    All routines use a standard calling convention designed for
    calling from translations, in which the incoming args are
@@ -630,6 +631,29 @@
 	ret
 
 
+/* Eight byte compare and exchange. */
+.globl VG_(helper_cmpxchg8b)
+VG_(helper_cmpxchg8b):
+        pushl %eax
+        pushl %ebx
+        pushl %ecx
+        pushl %edx
+        movl 20(%esp), %eax
+        movl 24(%esp), %edx
+        movl 28(%esp), %ebx
+        movl 32(%esp), %ecx
+        cmpxchg8b 36(%esp)
+        movl %eax, 20(%esp)
+        movl %edx, 24(%esp)
+        movl %ebx, 28(%esp)
+        movl %ecx, 32(%esp)
+        popl %edx
+        popl %ecx
+        popl %ebx
+        popl %eax
+        ret
+
+
 /* Undefined instruction (generates SIGILL) */
 .globl VG_(helper_undefined_instruction)
 VG_(helper_undefined_instruction):
diff --git a/coregrind/vg_include.h b/coregrind/vg_include.h
index a7f5f60..1e79e56 100644
--- a/coregrind/vg_include.h
+++ b/coregrind/vg_include.h
@@ -1745,6 +1745,8 @@
 extern void VG_(helper_DAS);
 extern void VG_(helper_DAA);
 
+extern void VG_(helper_cmpxchg8b);
+
 extern void VG_(helper_undefined_instruction);
 
 /* Information about trampoline code (for signal return and syscalls) */
diff --git a/coregrind/vg_main.c b/coregrind/vg_main.c
index d91f487..db93c7c 100644
--- a/coregrind/vg_main.c
+++ b/coregrind/vg_main.c
@@ -102,6 +102,7 @@
 Int VGOFF_(helper_LAHF) = INVALID_OFFSET;
 Int VGOFF_(helper_DAS) = INVALID_OFFSET;
 Int VGOFF_(helper_DAA) = INVALID_OFFSET;
+Int VGOFF_(helper_cmpxchg8b) = INVALID_OFFSET;
 Int VGOFF_(helper_undefined_instruction) = INVALID_OFFSET;
 
 /* MAX_NONCOMPACT_HELPERS can be increased easily.  If MAX_COMPACT_HELPERS is
@@ -422,6 +423,8 @@
       = alloc_BaB_1_set( (Addr) & VG_(helper_IN));
    VGOFF_(helper_OUT)
       = alloc_BaB_1_set( (Addr) & VG_(helper_OUT));
+   VGOFF_(helper_cmpxchg8b)
+      = alloc_BaB_1_set( (Addr) & VG_(helper_cmpxchg8b));
 
    VGOFF_(helper_undefined_instruction)
       = alloc_BaB_1_set( (Addr) & VG_(helper_undefined_instruction));
diff --git a/coregrind/vg_to_ucode.c b/coregrind/vg_to_ucode.c
index e05c449..0240ceb 100644
--- a/coregrind/vg_to_ucode.c
+++ b/coregrind/vg_to_ucode.c
@@ -2754,7 +2754,7 @@
 
    uInstr2(cb, GET, size, ArchReg, gregOfRM(rm), TempReg, src);
    uInstr2(cb, GET, size, ArchReg, R_EAX,        TempReg, acc);
-   uInstr2(cb, MOV, size, TempReg, acc,          TempReg, junk);
+   uInstr2(cb, MOV, 4,    TempReg, acc,          TempReg, junk);
    uInstr2(cb, SUB, size, TempReg, dest,         TempReg, junk);
    setFlagsFromUOpcode(cb, SUB);
 
@@ -2776,6 +2776,74 @@
 }
 
 
+static
+Addr dis_cmpxchg8b ( UCodeBlock* cb, 
+                     UChar       sorb,
+                     Addr        eip0 )
+{
+   Int   tal, tah, junkl, junkh, destl, desth, srcl, srch, accl, acch;
+   UChar dis_buf[50];
+   UChar rm;
+   UInt  pair;
+
+   rm    = getUChar(eip0);
+   accl  = newTemp(cb);
+   acch  = newTemp(cb);
+   srcl  = newTemp(cb);
+   srch  = newTemp(cb);
+   destl = newTemp(cb);
+   desth = newTemp(cb);
+   junkl = newTemp(cb);
+   junkh = newTemp(cb);
+
+   vg_assert(!epartIsReg(rm));
+
+   pair = disAMode ( cb, sorb, eip0, dis?dis_buf:NULL );
+   tal = LOW24(pair);
+   tah = newTemp(cb);
+   uInstr2(cb, MOV, 4, TempReg, tal, TempReg, tah);
+   uInstr2(cb, ADD, 4, Literal, 0, TempReg, tah);
+   uLiteral(cb, 4);
+   eip0 += HI8(pair);
+   if (dis) VG_(printf)("cmpxchg8b %s\n", dis_buf);
+   
+   uInstr0(cb, CALLM_S, 0);
+
+   uInstr2(cb, LOAD,  4, TempReg, tah, TempReg, desth);
+   uInstr1(cb, PUSH,  4, TempReg, desth);
+   uInstr2(cb, LOAD,  4, TempReg, tal, TempReg, destl);
+   uInstr1(cb, PUSH,  4, TempReg, destl);
+   uInstr2(cb, GET,   4, ArchReg, R_ECX, TempReg, srch);
+   uInstr1(cb, PUSH,  4, TempReg, srch);
+   uInstr2(cb, GET,   4, ArchReg, R_EBX, TempReg, srcl);
+   uInstr1(cb, PUSH,  4, TempReg, srcl);
+   uInstr2(cb, GET,   4, ArchReg, R_EDX, TempReg, acch);
+   uInstr1(cb, PUSH,  4, TempReg, acch);
+   uInstr2(cb, GET,   4, ArchReg, R_EAX, TempReg, accl);
+   uInstr1(cb, PUSH,  4, TempReg, accl);
+   
+   uInstr1(cb, CALLM, 0, Lit16,   VGOFF_(helper_cmpxchg8b));
+   uFlagsRWU(cb, FlagsEmpty, FlagZ, FlagsEmpty);
+   
+   uInstr1(cb, POP,   4, TempReg, accl);
+   uInstr2(cb, PUT,   4, TempReg, accl, ArchReg, R_EAX);
+   uInstr1(cb, POP,   4, TempReg, acch);
+   uInstr2(cb, PUT,   4, TempReg, acch, ArchReg, R_EDX);
+   uInstr1(cb, POP,   4, TempReg, srcl);
+   uInstr2(cb, PUT,   4, TempReg, srcl, ArchReg, R_EBX);
+   uInstr1(cb, POP,   4, TempReg, srch);
+   uInstr2(cb, PUT,   4, TempReg, srch, ArchReg, R_ECX);
+   uInstr1(cb, POP,   4, TempReg, destl);
+   uInstr2(cb, STORE, 4, TempReg, destl, TempReg, tal);
+   uInstr1(cb, POP,   4, TempReg, desth);
+   uInstr2(cb, STORE, 4, TempReg, desth, TempReg, tah);
+
+   uInstr0(cb, CALLM_E, 0);
+   
+   return eip0;
+}
+
+
 /* Handle conditional move instructions of the form
       cmovcc E(reg-or-mem), G(reg)
 
@@ -5886,9 +5954,15 @@
 
       /* =-=-=-=-=-=-=-=-=- CMPXCHG -=-=-=-=-=-=-=-=-=-= */
 
+      case 0xB0: /* CMPXCHG Gv,Ev */
+         eip = dis_cmpxchg_G_E ( cb, sorb, 1, eip );
+         break;
       case 0xB1: /* CMPXCHG Gv,Ev */
          eip = dis_cmpxchg_G_E ( cb, sorb, sz, eip );
          break;
+      case 0xC7: /* CMPXCHG8B Gv */
+         eip = dis_cmpxchg8b ( cb, sorb, eip );
+         break;
 
       /* =-=-=-=-=-=-=-=-=- CPUID -=-=-=-=-=-=-=-=-=-=-= */
 
diff --git a/include/vg_skin.h.base b/include/vg_skin.h.base
index cff8a22..25a42ee 100644
--- a/include/vg_skin.h.base
+++ b/include/vg_skin.h.base
@@ -1183,6 +1183,8 @@
 extern Int VGOFF_(helper_DAS);
 extern Int VGOFF_(helper_DAA);
 
+extern Int VGOFF_(helper_cmpxchg8b);
+
 
 /*====================================================================*/
 /*=== Generating x86 code from UCode                               ===*/