Chris Lattner cfa0f2edd3 Make the 2-address instruction lowering pass smarter in two ways: ... 1. If we are two-addressing a commutable instruction and the LHS is not the last use of the variable, see if the instruction is the last use of the RHS. If so, commute the instruction, allowing us to avoid a register-register copy in many cases for common instructions like ADD, OR, AND, etc on X86. 2. If #1 doesn't hold, and if this is an instruction that also existing in 3-address form, promote the instruction to a 3-address instruction to avoid the register-register copy. We can do this for several common instructions in X86, including ADDrr, INC, DEC, etc. This patch implements test/Regression/CodeGen/X86/commute-two-addr.ll, overlap-add.ll, and overlap-shift.ll when I check in the X86 support for it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19245 91177308-0d34-0410-b5e6-96231b3b80d8		2005-01-02 02:34:12 +00:00
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SelectionDAG
AsmPrinter.cpp
BranchFolding.cpp
IntrinsicLowering.cpp
LiveInterval.cpp
LiveInterval.h
LiveIntervalAnalysis.cpp
LiveIntervalAnalysis.h
LiveVariables.cpp
MachineBasicBlock.cpp
MachineCodeEmitter.cpp
MachineFunction.cpp
MachineInstr.cpp
Makefile
Passes.cpp
PHIElimination.cpp
PhysRegTracker.h
PrologEpilogInserter.cpp
RegAllocIterativeScan.cpp
RegAllocLinearScan.cpp
RegAllocLocal.cpp
RegAllocSimple.cpp
TwoAddressInstructionPass.cpp	Make the 2-address instruction lowering pass smarter in two ways:	2005-01-02 02:34:12 +00:00
UnreachableBlockElim.cpp
VirtRegMap.cpp
VirtRegMap.h