[llvm] r216910 - Fix left shifts of negative integers in AArch64 InstPrinter/Disassembler

[Alexey Samsonov]

Author: samsonov
Date: Tue Sep  2 11:19:41 2014
New Revision: 216910

URL: http://llvm.org/viewvc/llvm-project?rev=216910&view=rev
Log:
Fix left shifts of negative integers in AArch64 InstPrinter/Disassembler

Summary:
Left shift of negative integer is an undefined behavior, and
is reported by UBSan. It's ok for imm values to be negative, so we can
just replace left shifts with multiplications.

Test Plan: check-llvm test suite

Reviewers: t.p.northover

Reviewed By: t.p.northover

Subscribers: aemerson, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D5132

Modified:
    llvm/trunk/lib/Target/AArch64/Disassembler/AArch64Disassembler.cpp
    llvm/trunk/lib/Target/AArch64/InstPrinter/AArch64InstPrinter.cpp

Modified: llvm/trunk/lib/Target/AArch64/Disassembler/AArch64Disassembler.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/Disassembler/AArch64Disassembler.cpp?rev=216910&r1=216909&r2=216910&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/Disassembler/AArch64Disassembler.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/Disassembler/AArch64Disassembler.cpp Tue Sep  2 11:19:41 2014
@@ -610,7 +610,7 @@ static DecodeStatus DecodePCRelLabel19(l
   if (ImmVal & (1 << (19 - 1)))
     ImmVal |= ~((1LL << 19) - 1);
 
-  if (!Dis->tryAddingSymbolicOperand(Inst, ImmVal << 2, Addr,
+  if (!Dis->tryAddingSymbolicOperand(Inst, ImmVal *  4, Addr,
                                      Inst.getOpcode() != AArch64::LDRXl, 0, 4))
     Inst.addOperand(MCOperand::CreateImm(ImmVal));
   return Success;
@@ -1506,7 +1506,7 @@ static DecodeStatus DecodeUnconditionalB
   if (imm & (1 << (26 - 1)))
     imm |= ~((1LL << 26) - 1);
 
-  if (!Dis->tryAddingSymbolicOperand(Inst, imm << 2, Addr, true, 0, 4))
+  if (!Dis->tryAddingSymbolicOperand(Inst, imm * 4, Addr, true, 0, 4))
     Inst.addOperand(MCOperand::CreateImm(imm));
 
   return Success;
@@ -1548,7 +1548,7 @@ static DecodeStatus DecodeTestAndBranch(
   else
     DecodeGPR64RegisterClass(Inst, Rt, Addr, Decoder);
   Inst.addOperand(MCOperand::CreateImm(bit));
-  if (!Dis->tryAddingSymbolicOperand(Inst, dst << 2, Addr, true, 0, 4))
+  if (!Dis->tryAddingSymbolicOperand(Inst, dst * 4, Addr, true, 0, 4))
     Inst.addOperand(MCOperand::CreateImm(dst));
 
   return Success;

Modified: llvm/trunk/lib/Target/AArch64/InstPrinter/AArch64InstPrinter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/InstPrinter/AArch64InstPrinter.cpp?rev=216910&r1=216909&r2=216910&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/InstPrinter/AArch64InstPrinter.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/InstPrinter/AArch64InstPrinter.cpp Tue Sep  2 11:19:41 2014
@@ -1223,7 +1223,7 @@ void AArch64InstPrinter::printAlignedLab
   // If the label has already been resolved to an immediate offset (say, when
   // we're running the disassembler), just print the immediate.
   if (Op.isImm()) {
-    O << "#" << (Op.getImm() << 2);
+    O << "#" << (Op.getImm() * 4);
     return;
   }
 
@@ -1247,7 +1247,7 @@ void AArch64InstPrinter::printAdrpLabel(
   // If the label has already been resolved to an immediate offset (say, when
   // we're running the disassembler), just print the immediate.
   if (Op.isImm()) {
-    O << "#" << (Op.getImm() << 12);
+    O << "#" << (Op.getImm() * (1 << 12));
     return;
   }