Instructions with unique labels or embedded jumptables cannot be duplicated during ifcvt.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37606 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 31 insertions, 0 deletions

diff --git a/lib/Target/ARM/ARMInstrInfo.cpp b/lib/Target/ARM/ARMInstrInfo.cpp
index 1370faba4d..c8f7919eab 100644
--- a/lib/Target/ARM/ARMInstrInfo.cpp
+++ b/lib/Target/ARM/ARMInstrInfo.cpp
@@ -446,6 +446,35 @@ bool ARMInstrInfo::isPredicated(const MachineInstr *MI) const {
   return PIdx != -1 && MI->getOperand(PIdx).getImmedValue() != ARMCC::AL;
 }
 
+bool ARMInstrInfo::CanBeDuplicated(const MachineInstr *MI) const {
+  switch (MI->getOpcode()) {
+  default: return true;
+  // These have unique labels.
+  case ARM::PICADD:
+  case ARM::PICLD:
+  case ARM::PICLDZH:
+  case ARM::PICLDZB:
+  case ARM::PICLDH:
+  case ARM::PICLDB:
+  case ARM::PICLDSH:
+  case ARM::PICLDSB:
+  case ARM::PICSTR:
+  case ARM::PICSTRH:
+  case ARM::PICSTRB:
+  case ARM::LEApcrel:
+  case ARM::LEApcrelJT:
+  case ARM::tPICADD:
+  case ARM::tLEApcrel:
+  case ARM::tLEApcrelJT:
+  case ARM::CONSTPOOL_ENTRY:
+  // These embed jumptables.
+  case ARM::BR_JTr:
+  case ARM::BR_JTm:
+  case ARM::BR_JTadd:
+    return false;
+  }
+}
+
 bool ARMInstrInfo::PredicateInstruction(MachineInstr *MI,
                                 const std::vector<MachineOperand> &Pred) const {
   unsigned Opc = MI->getOpcode();
diff --git a/lib/Target/ARM/ARMInstrInfo.h b/lib/Target/ARM/ARMInstrInfo.h
index 5b406cb816..5c098f0f1a 100644
--- a/lib/Target/ARM/ARMInstrInfo.h
+++ b/lib/Target/ARM/ARMInstrInfo.h
@@ -106,6 +106,8 @@ public:
   // Predication support.
   virtual bool isPredicated(const MachineInstr *MI) const;
 
+  virtual bool CanBeDuplicated(const MachineInstr *MI) const;
+
   virtual
   bool PredicateInstruction(MachineInstr *MI,
                             const std::vector<MachineOperand> &Pred) const;