Author: evancheng
Date: Fri Feb 15 12:21:33 2008
New Revision: 47166
URL: http://llvm.org/viewvc/llvm-project?rev=47166&view=rev
Log:
Added CommuteChangesDestination(). This returns true if commuting the specified
machine instr will change its definition register.
Modified:
llvm/trunk/include/llvm/Target/TargetInstrInfo.h
llvm/trunk/lib/CodeGen/TargetInstrInfoImpl.cpp
Modified: llvm/trunk/include/llvm/Target/TargetInstrInfo.h
URL:
http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetInstrInfo.h?rev=47166&r1=47165&r2=47166&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Target/TargetInstrInfo.h (original)
+++ llvm/trunk/include/llvm/Target/TargetInstrInfo.h Fri Feb 15 12:21:33 2008
@@ -149,6 +149,14 @@
///
virtual MachineInstr *commuteInstruction(MachineInstr *MI) const = 0;
+ /// CommuteChangesDestination - Return true if commuting the specified
+ /// instruction will also changes the destination operand. Also return the
+ /// current operand index of the would be new destination register by
+ /// reference. This can happen when the commutable instruction is also a
+ /// two-address instruction.
+ virtual bool CommuteChangesDestination(MachineInstr *MI,
+ unsigned &OpIdx) const = 0;
+
/// AnalyzeBranch - Analyze the branching code at the end of MBB, returning
/// true if it cannot be understood (e.g. it's a switch dispatch or isn't
/// implemented for a target). Upon success, this returns false and returns
@@ -384,6 +392,8 @@
: TargetInstrInfo(desc, NumOpcodes) {}
public:
virtual MachineInstr *commuteInstruction(MachineInstr *MI) const;
+ virtual bool CommuteChangesDestination(MachineInstr *MI,
+ unsigned &OpIdx) const;
virtual bool PredicateInstruction(MachineInstr *MI,
const std::vector<MachineOperand> &Pred) const;
Modified: llvm/trunk/lib/CodeGen/TargetInstrInfoImpl.cpp
URL:
http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/TargetInstrInfoImpl.cpp?rev=47166&r1=47165&r2=47166&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/TargetInstrInfoImpl.cpp (original)
+++ llvm/trunk/lib/CodeGen/TargetInstrInfoImpl.cpp Fri Feb 15 12:21:33 2008
@@ -39,8 +39,28 @@
return MI;
}
+/// CommuteChangesDestination - Return true if commuting the specified
+/// instruction will also changes the destination operand. Also return the
+/// current operand index of the would be new destination register by
+/// reference. This can happen when the commutable instruction is also a
+/// two-address instruction.
+bool TargetInstrInfoImpl::CommuteChangesDestination(MachineInstr *MI,
+ unsigned &OpIdx) const{
+ assert(MI->getOperand(1).isRegister() && MI->getOperand(2).isRegister() &&
+ "This only knows how to commute register operands so far");
+ if (MI->getOperand(0).getReg() == MI->getOperand(1).getReg()) {
+ // Must be two address instruction!
+ assert(MI->getDesc().getOperandConstraint(0, TOI::TIED_TO) &&
+ "Expecting a two-address instruction!");
+ OpIdx = 2;
+ return true;
+ }
+ return false;
+}
+
+
bool TargetInstrInfoImpl::PredicateInstruction(MachineInstr *MI,
- const
std::vector<MachineOperand> &Pred) const {
+ const std::vector<MachineOperand> &Pred) const
{
bool MadeChange = false;
const TargetInstrDesc &TID = MI->getDesc();
if (!TID.isPredicable())
_______________________________________________
llvm-commits mailing list
llvm-commits@cs.uiuc.edu
http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
