From 7105259ce8e9fd78ce9fc1b7a9aaab123fb5db64 Mon Sep 17 00:00:00 2001
From: Eli Friedman <eli.friedman@gmail.com>
Date: Sat, 16 Jul 2011 02:41:28 +0000
Subject: [PATCH] Make the disassembler able to disassemble a bunch of
 instructions with names in the TableGen files containing "64" on x86-32. 
 This includes a bunch of x87 instructions, like fld, and a bunch of SSSE3
 instructions on MMX registers like pshufb.  Part of PR8873.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135337 91177308-0d34-0410-b5e6-96231b3b80d8
---
 test/MC/Disassembler/X86/x86-32.txt     | 26 +++++++++++++++++++++++++
 utils/TableGen/X86RecognizableInstr.cpp | 26 ++++++++++++++++++++++++-
 utils/TableGen/X86RecognizableInstr.h   |  2 ++
 3 files changed, 53 insertions(+), 1 deletion(-)
 create mode 100644 test/MC/Disassembler/X86/x86-32.txt

diff --git a/test/MC/Disassembler/X86/x86-32.txt b/test/MC/Disassembler/X86/x86-32.txt
new file mode 100644
index 00000000000..dd313f15810
--- /dev/null
+++ b/test/MC/Disassembler/X86/x86-32.txt
@@ -0,0 +1,26 @@
+# RUN: llvm-mc --disassemble %s -triple=i686-apple-darwin9 | FileCheck %s
+
+# Coverage
+
+# CHECK: pushl
+0xff 0x34 0x24
+
+# CHECK: popl
+0x58
+
+# CHECK: calll
+0xff 0xd0
+
+# CHECK: incl
+0x40
+
+# CHECK: leave
+0xc9
+
+# PR8873: some instructions not recognized in 32-bit mode
+
+# CHECK: fld
+0xdd 0x04 0x24
+
+# CHECK: pshufb
+0x0f 0x38 0x00 0xc0
diff --git a/utils/TableGen/X86RecognizableInstr.cpp b/utils/TableGen/X86RecognizableInstr.cpp
index f7518a988cc..ea3bb700b27 100644
--- a/utils/TableGen/X86RecognizableInstr.cpp
+++ b/utils/TableGen/X86RecognizableInstr.cpp
@@ -229,6 +229,30 @@ RecognizableInstr::RecognizableInstr(DisassemblerTables &tables,
   HasFROperands    = hasFROperands();
   HasVEX_LPrefix   = has256BitOperands() || Rec->getValueAsBit("hasVEX_L");
   
+  // Check for 64-bit inst which does not require REX
+  Is64Bit = false;
+  // FIXME: Is there some better way to check for In64BitMode?
+  std::vector<Record*> Predicates = Rec->getValueAsListOfDefs("Predicates");
+  for (unsigned i = 0, e = Predicates.size(); i != e; ++i) {
+    if (Predicates[i]->getName().find("64Bit") != Name.npos) {
+      Is64Bit = true;
+      break;
+    }
+  }
+  // FIXME: These instructions aren't marked as 64-bit in any way
+  Is64Bit |= Rec->getName() == "JMP64pcrel32" || 
+             Rec->getName() == "MASKMOVDQU64" || 
+             Rec->getName() == "POPFS64" || 
+             Rec->getName() == "POPGS64" || 
+             Rec->getName() == "PUSHFS64" || 
+             Rec->getName() == "PUSHGS64" ||
+             Rec->getName() == "REX64_PREFIX" ||
+             Rec->getName().find("VMREAD64") != Name.npos ||
+             Rec->getName().find("VMWRITE64") != Name.npos ||
+             Rec->getName().find("MOV64") != Name.npos || 
+             Rec->getName().find("PUSH64") != Name.npos ||
+             Rec->getName().find("POP64") != Name.npos;
+
   ShouldBeEmitted  = true;
 }
   
@@ -276,7 +300,7 @@ InstructionContext RecognizableInstr::insnContext() const {
       insnContext = IC_VEX_XS;
     else
       insnContext = IC_VEX;
-  } else if (Name.find("64") != Name.npos || HasREX_WPrefix) {
+  } else if (Is64Bit || HasREX_WPrefix) {
     if (HasREX_WPrefix && HasOpSizePrefix)
       insnContext = IC_64BIT_REXW_OPSIZE;
     else if (HasOpSizePrefix)
diff --git a/utils/TableGen/X86RecognizableInstr.h b/utils/TableGen/X86RecognizableInstr.h
index c7ec18ca6db..677d9f01554 100644
--- a/utils/TableGen/X86RecognizableInstr.h
+++ b/utils/TableGen/X86RecognizableInstr.h
@@ -64,6 +64,8 @@ private:
   bool HasLockPrefix;
   /// The isCodeGenOnly filed from the record
   bool IsCodeGenOnly;
+  // Whether the instruction has the predicate "Mode64Bit"
+  bool Is64Bit;
   
   /// The instruction name as listed in the tables
   std::string Name;