[RegBankSelect] Do not abort when the target wants to fall back.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279906 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 3 deletions

diff --git a/include/llvm/CodeGen/GlobalISel/RegBankSelect.h b/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
index 9faed91fd4d..ffd37875157 100644
--- a/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
+++ b/include/llvm/CodeGen/GlobalISel/RegBankSelect.h
@@ -74,6 +74,7 @@ class BlockFrequency;
 class MachineBranchProbabilityInfo;
 class MachineBlockFrequencyInfo;
 class MachineRegisterInfo;
+class TargetPassConfig;
 class TargetRegisterInfo;
 
 /// This pass implements the reg bank selector pass used in the GlobalISel
@@ -476,8 +477,12 @@ private:
   /// Optimization mode of the pass.
   Mode OptMode;
 
+  /// Current target configuration. Controls how the pass handles errors.
+  const TargetPassConfig *TPC;
+
   /// Assign the register bank of each operand of \p MI.
-  void assignInstr(MachineInstr &MI);
+  /// \return True on success, false otherwise.
+  bool assignInstr(MachineInstr &MI);
 
   /// Initialize the field members using \p MF.
   void init(MachineFunction &MF);
@@ -520,7 +525,9 @@ private:
   ///
   /// \note The caller is supposed to do the rewriting of op if need be.
   /// I.e., Reg = op ... => <NewRegs> = NewOp ...
-  void repairReg(MachineOperand &MO,
+  ///
+  /// \return True if the repairing worked, false otherwise.
+  bool repairReg(MachineOperand &MO,
                  const RegisterBankInfo::ValueMapping &ValMapping,
                  RegBankSelect::RepairingPlacement &RepairPt,
                  const iterator_range<SmallVectorImpl<unsigned>::const_iterator>
@@ -570,7 +577,8 @@ private:
   /// Apply \p Mapping to \p MI. \p RepairPts represents the different
   /// mapping action that need to happen for the mapping to be
   /// applied.
-  void applyMapping(MachineInstr &MI,
+  /// \return True if the mapping was applied sucessfully, false otherwise.
+  bool applyMapping(MachineInstr &MI,
                     const RegisterBankInfo::InstructionMapping &InstrMapping,
                     SmallVectorImpl<RepairingPlacement> &RepairPts);