[llvm-commits] CVS: llvm/lib/Target/X86/X86InstrInfo.cpp X86InstrInfo.h

[Chris Lattner]

Changes in directory llvm/lib/Target/X86:

X86InstrInfo.cpp updated: 1.68 -> 1.69
X86InstrInfo.h updated: 1.57 -> 1.58
---
Log message:

Implement support for branch condition reversal.


---
Diffs of the changes:  (+33 -2)

 X86InstrInfo.cpp |   30 ++++++++++++++++++++++++++++--
 X86InstrInfo.h   |    5 +++++
 2 files changed, 33 insertions(+), 2 deletions(-)


Index: llvm/lib/Target/X86/X86InstrInfo.cpp
diff -u llvm/lib/Target/X86/X86InstrInfo.cpp:1.68 llvm/lib/Target/X86/X86InstrInfo.cpp:1.69
--- llvm/lib/Target/X86/X86InstrInfo.cpp:1.68	Sat Oct 21 00:42:09 2006
+++ llvm/lib/Target/X86/X86InstrInfo.cpp	Sat Oct 21 00:52:40 2006
@@ -290,6 +290,31 @@
   }
 }
 
+/// GetOppositeBranchCondition - Return the inverse of the specified condition,
+/// e.g. turning COND_E to COND_NE.
+X86::CondCode X86::GetOppositeBranchCondition(X86::CondCode CC) {
+  switch (CC) {
+  default: assert(0 && "Illegal condition code!");
+  case X86::COND_E:  return X86::COND_NE;
+  case X86::COND_NE: return X86::COND_E;
+  case X86::COND_L:  return X86::COND_GE;
+  case X86::COND_LE: return X86::COND_G;
+  case X86::COND_G:  return X86::COND_LE;
+  case X86::COND_GE: return X86::COND_L;
+  case X86::COND_B:  return X86::COND_AE;
+  case X86::COND_BE: return X86::COND_A;
+  case X86::COND_A:  return X86::COND_BE;
+  case X86::COND_AE: return X86::COND_B;
+  case X86::COND_S:  return X86::COND_NS;
+  case X86::COND_NS: return X86::COND_S;
+  case X86::COND_P:  return X86::COND_NP;
+  case X86::COND_NP: return X86::COND_P;
+  case X86::COND_O:  return X86::COND_NO;
+  case X86::COND_NO: return X86::COND_O;
+  }
+}
+
+
 bool X86InstrInfo::AnalyzeBranch(MachineBasicBlock &MBB, 
                                  MachineBasicBlock *&TBB,
                                  MachineBasicBlock *&FBB,
@@ -397,8 +422,9 @@
 
 bool X86InstrInfo::
 ReverseBranchCondition(std::vector<MachineOperand> &Cond) const {
-  // TODO: IMPLEMENT.
-  return true;
+  assert(Cond.size() == 1 && "Invalid X86 branch condition!");
+  Cond[0].setImm(GetOppositeBranchCondition((X86::CondCode)Cond[0].getImm()));
+  return false;
 }
 
 const TargetRegisterClass *X86InstrInfo::getPointerRegClass() const {


Index: llvm/lib/Target/X86/X86InstrInfo.h
diff -u llvm/lib/Target/X86/X86InstrInfo.h:1.57 llvm/lib/Target/X86/X86InstrInfo.h:1.58
--- llvm/lib/Target/X86/X86InstrInfo.h:1.57	Fri Oct 20 12:42:20 2006
+++ llvm/lib/Target/X86/X86InstrInfo.h	Sat Oct 21 00:52:40 2006
@@ -46,6 +46,11 @@
   
   // Turn condition code into conditional branch opcode.
   unsigned GetCondBranchFromCond(CondCode CC);
+  
+  /// GetOppositeBranchCondition - Return the inverse of the specified cond,
+  /// e.g. turning COND_E to COND_NE.
+  CondCode GetOppositeBranchCondition(X86::CondCode CC);
+
 }
   
 /// X86II - This namespace holds all of the target specific flags that