If the insert_subreg source is <undef>, insert an implicit_def instead of a copy.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78141 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2009-08-05 01:29:24 +00:00
parent a5225add0d
commit 518ad1a880
2 changed files with 42 additions and 2 deletions

View File

@ -254,6 +254,12 @@ bool LowerSubregsInstructionPass::LowerInsert(MachineInstr *MI) {
// Insert sub-register copy
const TargetRegisterClass *TRC0= TRI.getPhysicalRegisterRegClass(DstSubReg);
const TargetRegisterClass *TRC1= TRI.getPhysicalRegisterRegClass(InsReg);
if (MI->getOperand(2).isUndef())
// If the source register being inserted is undef, then this becomes an
// implicit_def.
BuildMI(*MBB, MI, MI->getDebugLoc(),
TII.get(TargetInstrInfo::IMPLICIT_DEF), DstSubReg);
else
TII.copyRegToReg(*MBB, MI, DstSubReg, InsReg, TRC0, TRC1);
MachineBasicBlock::iterator CopyMI = MI;
--CopyMI;
@ -270,7 +276,7 @@ bool LowerSubregsInstructionPass::LowerInsert(MachineInstr *MI) {
}
// Make sure the inserted register gets killed
if (MI->getOperand(2).isKill())
if (MI->getOperand(2).isKill() && !MI->getOperand(2).isUndef())
TransferKillFlag(MI, InsReg, TRI);
}

View File

@ -0,0 +1,34 @@
; RUN: llvm-as < %s | llc -mtriple=thumbv7-apple-darwin9 -mattr=+neon,+neonfp
; RUN: llvm-as < %s | llc -mtriple=thumbv7-apple-darwin9 -mattr=+neon,+neonfp | grep fcpys | count 1
; rdar://7117307
%struct.Hosp = type { i32, i32, i32, %struct.List, %struct.List, %struct.List, %struct.List }
%struct.List = type { %struct.List*, %struct.Patient*, %struct.List* }
%struct.Patient = type { i32, i32, i32, %struct.Village* }
%struct.Results = type { float, float, float }
%struct.Village = type { [4 x %struct.Village*], %struct.Village*, %struct.List, %struct.Hosp, i32, i32 }
define arm_apcscc void @get_results(%struct.Results* noalias nocapture sret %agg.result, %struct.Village* %village) nounwind {
entry:
br i1 undef, label %bb, label %bb6.preheader
bb6.preheader: ; preds = %entry
call void @llvm.memcpy.i32(i8* undef, i8* undef, i32 12, i32 4)
br i1 undef, label %bb15, label %bb13
bb: ; preds = %entry
ret void
bb13: ; preds = %bb13, %bb6.preheader
%0 = fadd float undef, undef ; <float> [#uses=1]
%1 = fadd float undef, 1.000000e+00 ; <float> [#uses=1]
br i1 undef, label %bb15, label %bb13
bb15: ; preds = %bb13, %bb6.preheader
%r1.0.0.lcssa = phi float [ 0.000000e+00, %bb6.preheader ], [ %1, %bb13 ] ; <float> [#uses=1]
%r1.1.0.lcssa = phi float [ undef, %bb6.preheader ], [ %0, %bb13 ] ; <float> [#uses=0]
store float %r1.0.0.lcssa, float* undef, align 4
ret void
}
declare void @llvm.memcpy.i32(i8* nocapture, i8* nocapture, i32, i32) nounwind