Merging r202774:

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r202774 | reid | 2014-03-03 19:33:17 -0500 (Mon, 03 Mar 2014) | 7 lines

MC: Fix Intel assembly parser for [global + offset]

We were dropping the displacement on the floor if we also had some
immediate offset.

Should fix PR19033.

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llvm-svn: 206061

2 files changed, 35 insertions, 14 deletions

diff --git a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
index 2afba6b75a82..22b79b3b2844 100644
--- a/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
+++ b/llvm/lib/Target/X86/AsmParser/X86AsmParser.cpp
@@ -1181,16 +1181,23 @@ X86AsmParser::CreateMemForInlineAsm(unsigned SegReg, const MCExpr *Disp,
                                     unsigned Scale, SMLoc Start, SMLoc End,
                                     unsigned Size, StringRef Identifier,
                                     InlineAsmIdentifierInfo &Info){
-  if (isa<MCSymbolRefExpr>(Disp)) {
-    // If this is not a VarDecl then assume it is a FuncDecl or some other label
-    // reference.  We need an 'r' constraint here, so we need to create register
-    // operand to ensure proper matching.  Just pick a GPR based on the size of
-    // a pointer.
-    if (!Info.IsVarDecl) {
-      unsigned RegNo = is64BitMode() ? X86::RBX : X86::EBX;
-      return X86Operand::CreateReg(RegNo, Start, End, /*AddressOf=*/true,
-                                   SMLoc(), Identifier, Info.OpDecl);
-    }
+  // If this is not a VarDecl then assume it is a FuncDecl or some other label
+  // reference.  We need an 'r' constraint here, so we need to create register
+  // operand to ensure proper matching.  Just pick a GPR based on the size of
+  // a pointer.
+  if (isa<MCSymbolRefExpr>(Disp) && !Info.IsVarDecl) {
+    unsigned RegNo = is64BitMode() ? X86::RBX : X86::EBX;
+    return X86Operand::CreateReg(RegNo, Start, End, /*AddressOf=*/true,
+                                 SMLoc(), Identifier, Info.OpDecl);
+  }
+
+  // We either have a direct symbol reference, or an offset from a symbol.  The
+  // parser always puts the symbol on the LHS, so look there for size
+  // calculation purposes.
+  const MCBinaryExpr *BinOp = dyn_cast<MCBinaryExpr>(Disp);
+  bool IsSymRef =
+      isa<MCSymbolRefExpr>(BinOp ? BinOp->getLHS() : Disp);
+  if (IsSymRef) {
     if (!Size) {
       Size = Info.Type * 8; // Size is in terms of bits in this context.
       if (Size)
@@ -1371,7 +1378,7 @@ X86Operand *X86AsmParser::ParseIntelBracExpression(unsigned SegReg, SMLoc Start,
   if (ParseIntelExpression(SM, End))
     return 0;
 
-  const MCExpr *Disp;
+  const MCExpr *Disp = 0;
   if (const MCExpr *Sym = SM.getSym()) {
     // A symbolic displacement.
     Disp = Sym;
@@ -1379,9 +1386,14 @@ X86Operand *X86AsmParser::ParseIntelBracExpression(unsigned SegReg, SMLoc Start,
       RewriteIntelBracExpression(InstInfo->AsmRewrites, SM.getSymName(),
                                  ImmDisp, SM.getImm(), BracLoc, StartInBrac,
                                  End);
-  } else {
-    // An immediate displacement only.   
-    Disp = MCConstantExpr::Create(SM.getImm(), getContext());
+  }
+
+  if (SM.getImm() || !Disp) {
+    const MCExpr *Imm = MCConstantExpr::Create(SM.getImm(), getContext());
+    if (Disp)
+      Disp = MCBinaryExpr::CreateAdd(Disp, Imm, getContext());
+    else
+      Disp = Imm;  // An immediate displacement only.
   }
 
   // Parse struct field access.  Intel requires a dot, but MSVC doesn't.  MSVC
diff --git a/llvm/test/MC/X86/intel-syntax.s b/llvm/test/MC/X86/intel-syntax.s
index 9677da731c17..50f29e0a64c9 100644
--- a/llvm/test/MC/X86/intel-syntax.s
+++ b/llvm/test/MC/X86/intel-syntax.s
@@ -584,3 +584,12 @@ fsub ST(1)
 fsubr ST(1)
 fdiv ST(1)
 fdivr ST(1)
+
+.bss
+.globl _g0
+.text
+
+// CHECK: movq _g0, %rbx
+// CHECK: movq _g0+8, %rcx
+mov rbx, qword ptr [_g0]
+mov rcx, qword ptr [_g0 + 8]