Add a Thumb BRIND pattern. Change the ARM BRIND assembly to separate the

opcode and operand with a tab.  Check for these instructions in the usual
places.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85411 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/ARM/ARMBaseInstrInfo.cpp

@@ -249,7 +249,8 @@ ARMBaseInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB,
   // ...likewise if it ends with a branch table followed by an unconditional
   // branch. The branch folder can create these, and we must get rid of them for
   // correctness of Thumb constant islands.
-  if (isJumpTableBranchOpcode(SecondLastOpc) &&
+  if ((isJumpTableBranchOpcode(SecondLastOpc) ||
+       isIndirectBranchOpcode(SecondLastOpc)) &&
       isUncondBranchOpcode(LastOpc)) {
     I = LastInst;
     if (AllowModify)

lib/Target/ARM/ARMBaseInstrInfo.h

@@ -293,6 +293,11 @@ bool isJumpTableBranchOpcode(int Opc) {
     Opc == ARM::tBR_JTr || Opc == ARM::t2BR_JT;
 }
 
+static inline
+bool isIndirectBranchOpcode(int Opc) {
+  return Opc == ARM::BRIND || Opc == ARM::tBRIND;
+}
+
 /// getInstrPredicate - If instruction is predicated, returns its predicate
 /// condition, otherwise returns AL. It also returns the condition code
 /// register by reference.

lib/Target/ARM/ARMInstrInfo.cpp

@@ -67,6 +67,7 @@ bool ARMInstrInfo::BlockHasNoFallThrough(const MachineBasicBlock &MBB) const {
   case ARM::BX_RET:   // Return.
   case ARM::LDM_RET:
   case ARM::B:
+  case ARM::BRIND:
   case ARM::BR_JTr:   // Jumptable branch.
   case ARM::BR_JTm:   // Jumptable branch through mem.
   case ARM::BR_JTadd: // Jumptable branch add to pc.

lib/Target/ARM/ARMInstrInfo.td

@@ -659,7 +659,7 @@ let isReturn = 1, isTerminator = 1, isBarrier = 1 in
 
 // Indirect branches
 let isBranch = 1, isTerminator = 1, isBarrier = 1, isIndirectBranch = 1 in {
-  def BRIND : AXI<(outs), (ins GPR:$dst), BrMiscFrm, IIC_Br, "bx $dst",
+  def BRIND : AXI<(outs), (ins GPR:$dst), BrMiscFrm, IIC_Br, "bx\t$dst",
                   [(brind GPR:$dst)]> {
     let Inst{7-4}   = 0b0001;
     let Inst{19-8}  = 0b111111111111;

lib/Target/ARM/ARMInstrThumb.td

@@ -180,6 +180,12 @@ let isReturn = 1, isTerminator = 1, isBarrier = 1 in {
   def tBX_RET_vararg : TI<(outs), (ins tGPR:$target), IIC_Br, "bx\t$target", []>;
 }
 
+// Indirect branches
+let isBranch = 1, isTerminator = 1, isBarrier = 1, isIndirectBranch = 1 in {
+  def tBRIND : TI<(outs), (ins GPR:$dst), IIC_Br, "bx\t$dst",
+                  [(brind GPR:$dst)]>;
+}
+
 // FIXME: remove when we have a way to marking a MI with these properties.
 let isReturn = 1, isTerminator = 1, isBarrier = 1, mayLoad = 1,
     hasExtraDefRegAllocReq = 1 in

lib/Target/ARM/Thumb1InstrInfo.cpp

@@ -38,6 +38,7 @@ Thumb1InstrInfo::BlockHasNoFallThrough(const MachineBasicBlock &MBB) const {
   case ARM::tBX_RET_vararg:
   case ARM::tPOP_RET:
   case ARM::tB:
+  case ARM::tBRIND:
   case ARM::tBR_JTr:
     return true;
   default:

lib/Target/ARM/Thumb2InstrInfo.cpp

@@ -46,6 +46,7 @@ Thumb2InstrInfo::BlockHasNoFallThrough(const MachineBasicBlock &MBB) const {
   case ARM::tBX_RET_vararg:
   case ARM::tPOP_RET:
   case ARM::tB:
+  case ARM::tBRIND:
     return true;
   default:
     break;