3 files changed, 81 insertions, 20 deletions

diff --git a/lib/Target/SystemZ/AsmParser/SystemZAsmParser.cpp b/lib/Target/SystemZ/AsmParser/SystemZAsmParser.cpp
index d13234c..7f2159f 100644
--- a/lib/Target/SystemZ/AsmParser/SystemZAsmParser.cpp
+++ b/lib/Target/SystemZ/AsmParser/SystemZAsmParser.cpp
@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "MCTargetDesc/SystemZMCTargetDesc.h"
+#include "llvm/MC/MCContext.h"
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
@@ -368,6 +369,17 @@ public:
   }
   OperandMatchResultTy
   parseAccessReg(SmallVectorImpl<MCParsedAsmOperand*> &Operands);
+  OperandMatchResultTy
+  parsePCRel(SmallVectorImpl<MCParsedAsmOperand*> &Operands,
+             int64_t MinVal, int64_t MaxVal);
+  OperandMatchResultTy
+  parsePCRel16(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
+    return parsePCRel(Operands, -(1LL << 16), (1LL << 16) - 1);
+  }
+  OperandMatchResultTy
+  parsePCRel32(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
+    return parsePCRel(Operands, -(1LL << 32), (1LL << 32) - 1);
+  }
 };
 }
 
@@ -653,6 +665,37 @@ parseAccessReg(SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
   return MatchOperand_Success;
 }
 
+SystemZAsmParser::OperandMatchResultTy SystemZAsmParser::
+parsePCRel(SmallVectorImpl<MCParsedAsmOperand*> &Operands,
+           int64_t MinVal, int64_t MaxVal) {
+  MCContext &Ctx = getContext();
+  MCStreamer &Out = getStreamer();
+  const MCExpr *Expr;
+  SMLoc StartLoc = Parser.getTok().getLoc();
+  if (getParser().parseExpression(Expr))
+    return MatchOperand_NoMatch;
+
+  // For consistency with the GNU assembler, treat immediates as offsets
+  // from ".".
+  if (const MCConstantExpr *CE = dyn_cast<MCConstantExpr>(Expr)) {
+    int64_t Value = CE->getValue();
+    if ((Value & 1) || Value < MinVal || Value > MaxVal) {
+      Error(StartLoc, "offset out of range");
+      return MatchOperand_ParseFail;
+    }
+    MCSymbol *Sym = Ctx.CreateTempSymbol();
+    Out.EmitLabel(Sym);
+    const MCExpr *Base = MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_None,
+                                                 Ctx);
+    Expr = Value == 0 ? Base : MCBinaryExpr::CreateAdd(Base, Expr, Ctx);
+  }
+
+  SMLoc EndLoc =
+    SMLoc::getFromPointer(Parser.getTok().getLoc().getPointer() - 1);
+  Operands.push_back(SystemZOperand::createImm(Expr, StartLoc, EndLoc));
+  return MatchOperand_Success;
+}
+
 // Force static initialization.
 extern "C" void LLVMInitializeSystemZAsmParser() {
   RegisterMCAsmParser<SystemZAsmParser> X(TheSystemZTarget);
diff --git a/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp b/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
index 70a3eb9..7721b1f 100644
--- a/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
+++ b/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
@@ -162,19 +162,19 @@ SystemZMCCodeEmitter::getPCRelEncoding(const MCInst &MI, unsigned OpNum,
                                        SmallVectorImpl<MCFixup> &Fixups,
                                        unsigned Kind, int64_t Offset) const {
   const MCOperand &MO = MI.getOperand(OpNum);
-  // For compatibility with the GNU assembler, treat constant operands as
-  // unadjusted PC-relative offsets.
+  const MCExpr *Expr;
   if (MO.isImm())
-    return MO.getImm() / 2;
-
-  const MCExpr *Expr = MO.getExpr();
-  if (Offset) {
-    // The operand value is relative to the start of MI, but the fixup
-    // is relative to the operand field itself, which is Offset bytes
-    // into MI.  Add Offset to the relocation value to cancel out
-    // this difference.
-    const MCExpr *OffsetExpr = MCConstantExpr::Create(Offset, Ctx);
-    Expr = MCBinaryExpr::CreateAdd(Expr, OffsetExpr, Ctx);
+    Expr = MCConstantExpr::Create(MO.getImm() + Offset, Ctx);
+  else {
+    Expr = MO.getExpr();
+    if (Offset) {
+      // The operand value is relative to the start of MI, but the fixup
+      // is relative to the operand field itself, which is Offset bytes
+      // into MI.  Add Offset to the relocation value to cancel out
+      // this difference.
+      const MCExpr *OffsetExpr = MCConstantExpr::Create(Offset, Ctx);
+      Expr = MCBinaryExpr::CreateAdd(Expr, OffsetExpr, Ctx);
+    }
   }
   Fixups.push_back(MCFixup::Create(Offset, Expr, (MCFixupKind)Kind));
   return 0;
diff --git a/lib/Target/SystemZ/SystemZOperands.td b/lib/Target/SystemZ/SystemZOperands.td
index 829306f..770b7f5 100644
--- a/lib/Target/SystemZ/SystemZOperands.td
+++ b/lib/Target/SystemZ/SystemZOperands.td
@@ -27,11 +27,25 @@ class Immediate<ValueType vt, code pred, SDNodeXForm xform, string asmop>
   let ParserMatchClass = !cast<AsmOperandClass>(asmop);
 }
 
+// Constructs an asm operand for a PC-relative address.  SIZE says how
+// many bits there are.
+class PCRelAsmOperand<string size> : ImmediateAsmOperand<"PCRel"##size> {
+  let PredicateMethod = "isImm";
+  let ParserMethod = "parsePCRel"##size;
+}
+
+// Constructs an operand for a PC-relative address with address type VT.
+// ASMOP is the associated asm operand.
+class PCRelOperand<ValueType vt, AsmOperandClass asmop> : Operand<vt> {
+  let ParserMatchClass = asmop;
+}
+
 // Constructs both a DAG pattern and instruction operand for a PC-relative
-// address with address size VT.  SELF is the name of the operand.
-class PCRelAddress<ValueType vt, string self>
+// address with address size VT.  SELF is the name of the operand and
+// ASMOP is the associated asm operand.
+class PCRelAddress<ValueType vt, string self, AsmOperandClass asmop>
   : ComplexPattern<vt, 1, "selectPCRelAddress", [z_pcrel_wrapper]>,
-    Operand<vt> {
+    PCRelOperand<vt, asmop> {
   let MIOperandInfo = (ops !cast<Operand>(self));
 }
 
@@ -337,28 +351,32 @@ def fpimmneg0 : PatLeaf<(fpimm), [{ return N->isExactlyValue(-0.0); }]>;
 // Symbolic address operands
 //===----------------------------------------------------------------------===//
 
+// PC-relative asm operands.
+def PCRel16 : PCRelAsmOperand<"16">;
+def PCRel32 : PCRelAsmOperand<"32">;
+
 // PC-relative offsets of a basic block.  The offset is sign-extended
 // and multiplied by 2.
-def brtarget16 : Operand<OtherVT> {
+def brtarget16 : PCRelOperand<OtherVT, PCRel16> {
   let EncoderMethod = "getPC16DBLEncoding";
 }
-def brtarget32 : Operand<OtherVT> {
+def brtarget32 : PCRelOperand<OtherVT, PCRel32> {
   let EncoderMethod = "getPC32DBLEncoding";
 }
 
 // A PC-relative offset of a global value.  The offset is sign-extended
 // and multiplied by 2.
-def pcrel32 : PCRelAddress<i64, "pcrel32"> {
+def pcrel32 : PCRelAddress<i64, "pcrel32", PCRel32> {
   let EncoderMethod = "getPC32DBLEncoding";
 }
 
 // A PC-relative offset of a global value when the value is used as a
 // call target.  The offset is sign-extended and multiplied by 2.
-def pcrel16call : PCRelAddress<i64, "pcrel16call"> {
+def pcrel16call : PCRelAddress<i64, "pcrel16call", PCRel16> {
   let PrintMethod = "printCallOperand";
   let EncoderMethod = "getPLT16DBLEncoding";
 }
-def pcrel32call : PCRelAddress<i64, "pcrel32call"> {
+def pcrel32call : PCRelAddress<i64, "pcrel32call", PCRel32> {
   let PrintMethod = "printCallOperand";
   let EncoderMethod = "getPLT32DBLEncoding";
 }