[mips] [IAS] Fix LW with relative label operands.

Summary:
Previously, MCSymbolRefExpr::create() was called with a StringRef of the symbol
name, which it would then search for in the Symbols StringMap (from MCContext).

However, relative labels (which are temporary symbols) are apparently not stored
in the Symbols StringMap, so we end up creating a new {$,.L}tmp symbol
({$,.L}tmp00, {$,.L}tmp10 etc.) each time we create an MCSymbolRefExpr by
passing in the symbol name as a StringRef.

Fortunately, there is a version of MCSymbolRefExpr::create() which takes an
MCSymbol* and we already have an MCSymbol* at that point, so we can just pass
that in instead of the StringRef.

I also removed the local StringRef calls to MCSymbolRefExpr::create() from
expandMemInst(), as those cases can be handled by evaluateRelocExpr() anyway.

Reviewers: dsanders

Reviewed By: dsanders

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D9938

llvm-svn: 239897

diff --git a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
index 7750441..da3c0ab 100644 (file)
--- a/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
+++ b/llvm/lib/Target/Mips/AsmParser/MipsAsmParser.cpp
@@ -2105,7 +2105,6 @@ bool MipsAsmParser::expandBranchImm(MCInst &Inst, SMLoc IDLoc,
 void MipsAsmParser::expandMemInst(MCInst &Inst, SMLoc IDLoc,
                                   SmallVectorImpl<MCInst> &Instructions,
                                   bool isLoad, bool isImmOpnd) {
-  const MCSymbolRefExpr *SR;
   MCInst TempInst;
   unsigned ImmOffset, HiOffset, LoOffset;
   const MCExpr *ExprOffset;
@@ -2172,16 +2171,8 @@ void MipsAsmParser::expandMemInst(MCInst &Inst, SMLoc IDLoc,
   if (isImmOpnd)
     TempInst.addOperand(MCOperand::createImm(HiOffset));
   else {
-    if (ExprOffset->getKind() == MCExpr::SymbolRef) {
-      SR = static_cast<const MCSymbolRefExpr *>(ExprOffset);
-      const MCSymbolRefExpr *HiExpr = MCSymbolRefExpr::create(
-          SR->getSymbol().getName(), MCSymbolRefExpr::VK_Mips_ABS_HI,
-          getContext());
-      TempInst.addOperand(MCOperand::createExpr(HiExpr));
-    } else {
-      const MCExpr *HiExpr = evaluateRelocExpr(ExprOffset, "hi");
-      TempInst.addOperand(MCOperand::createExpr(HiExpr));
-    }
+    const MCExpr *HiExpr = evaluateRelocExpr(ExprOffset, "hi");
+    TempInst.addOperand(MCOperand::createExpr(HiExpr));
   }
   // Add the instruction to the list.
   Instructions.push_back(TempInst);
@@ -2204,15 +2195,8 @@ void MipsAsmParser::expandMemInst(MCInst &Inst, SMLoc IDLoc,
   if (isImmOpnd)
     TempInst.addOperand(MCOperand::createImm(LoOffset));
   else {
-    if (ExprOffset->getKind() == MCExpr::SymbolRef) {
-      const MCSymbolRefExpr *LoExpr = MCSymbolRefExpr::create(
-          SR->getSymbol().getName(), MCSymbolRefExpr::VK_Mips_ABS_LO,
-          getContext());
-      TempInst.addOperand(MCOperand::createExpr(LoExpr));
-    } else {
-      const MCExpr *LoExpr = evaluateRelocExpr(ExprOffset, "lo");
-      TempInst.addOperand(MCOperand::createExpr(LoExpr));
-    }
+    const MCExpr *LoExpr = evaluateRelocExpr(ExprOffset, "lo");
+    TempInst.addOperand(MCOperand::createExpr(LoExpr));
   }
   Instructions.push_back(TempInst);
   TempInst.clear();
@@ -2642,7 +2626,7 @@ const MCExpr *MipsAsmParser::evaluateRelocExpr(const MCExpr *Expr,
 
   if (const MCSymbolRefExpr *MSRE = dyn_cast<MCSymbolRefExpr>(Expr)) {
     // It's a symbol, create a symbolic expression from the symbol.
-    StringRef Symbol = MSRE->getSymbol().getName();
+    const MCSymbol *Symbol = &MSRE->getSymbol();
     MCSymbolRefExpr::VariantKind VK = getVariantKind(RelocStr);
     Res = MCSymbolRefExpr::create(Symbol, VK, getContext());
     return Res;

diff --git a/llvm/test/MC/Mips/mips-expansions.s b/llvm/test/MC/Mips/mips-expansions.s
index 0491c31..c32552f 100644 (file)
--- a/llvm/test/MC/Mips/mips-expansions.s
+++ b/llvm/test/MC/Mips/mips-expansions.s
@@ -55,6 +55,12 @@
 # CHECK: sw      $10, %lo(symbol)($1)    # encoding: [A,A,0x2a,0xac]
 # CHECK:                                 #   fixup A - offset: 0, value: symbol@ABS_LO, kind: fixup_Mips_LO16
 
+  lw $8, 1f
+# CHECK: lui $8, %hi($tmp0)              # encoding: [A,A,0x08,0x3c]
+# CHECK:                                 #   fixup A - offset: 0, value: ($tmp0)@ABS_HI, kind: fixup_Mips_HI16
+# CHECK: lw  $8, %lo($tmp0)($8)          # encoding: [A,A,0x08,0x8d]
+# CHECK:                                 #   fixup A - offset: 0, value: ($tmp0)@ABS_LO, kind: fixup_Mips_LO16
+
   lw $10, 655483($4)
 # CHECK: lui     $10, 10                 # encoding: [0x0a,0x00,0x0a,0x3c]
 # CHECK: addu    $10, $10, $4            # encoding: [0x21,0x50,0x44,0x01]
@@ -145,3 +151,6 @@
 # CHECK: lui   $1, 1             # encoding: [0x01,0x00,0x01,0x3c]
 # CHECK: beq   $2, $1, 1332      # encoding: [0x4d,0x01,0x41,0x10]
 # CHECK: nop                     # encoding: [0x00,0x00,0x00,0x00]
+
+1:
+  add $4, $4, $4