From ada5d6c37e2938fe56719ea37d9581320222998c Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Sun, 12 Apr 2009 07:45:01 +0000 Subject: optimize FastISel::UpdateValueMap to avoid duplicate map lookups, and make it return the assigned register. llvm-svn: 68888 --- llvm/lib/CodeGen/SelectionDAG/FastISel.cpp | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) (limited to 'llvm/lib/CodeGen/SelectionDAG/FastISel.cpp') diff --git a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp index 8467330bb9b..7e300536748 100644 --- a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp @@ -149,16 +149,21 @@ unsigned FastISel::lookUpRegForValue(Value *V) { /// NOTE: This is only necessary because we might select a block that uses /// a value before we select the block that defines the value. It might be /// possible to fix this by selecting blocks in reverse postorder. -void FastISel::UpdateValueMap(Value* I, unsigned Reg) { +unsigned FastISel::UpdateValueMap(Value* I, unsigned Reg) { if (!isa(I)) { LocalValueMap[I] = Reg; - return; + return Reg; + } + + unsigned &AssignedReg = ValueMap[I]; + if (AssignedReg == 0) + AssignedReg = Reg; + else { + const TargetRegisterClass *RegClass = MRI.getRegClass(Reg); + TII.copyRegToReg(*MBB, MBB->end(), AssignedReg, + Reg, RegClass, RegClass); } - if (!ValueMap.count(I)) - ValueMap[I] = Reg; - else - TII.copyRegToReg(*MBB, MBB->end(), ValueMap[I], - Reg, MRI.getRegClass(Reg), MRI.getRegClass(Reg)); + return AssignedReg; } unsigned FastISel::getRegForGEPIndex(Value *Idx) { -- cgit v1.2.3