diff options
| -rw-r--r-- | llvm/lib/CodeGen/LiveIntervals.cpp | 12 | ||||
| -rw-r--r-- | llvm/test/CodeGen/AMDGPU/live-intervals-multiple-dead-defs.mir | 18 |
2 files changed, 29 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/LiveIntervals.cpp b/llvm/lib/CodeGen/LiveIntervals.cpp index 0781a0b121b..2d5b8e79910 100644 --- a/llvm/lib/CodeGen/LiveIntervals.cpp +++ b/llvm/lib/CodeGen/LiveIntervals.cpp @@ -196,7 +196,11 @@ void LiveIntervals::computeVirtRegInterval(LiveInterval &LI) { assert(LI.empty() && "Should only compute empty intervals."); LRCalc->reset(MF, getSlotIndexes(), DomTree, &getVNInfoAllocator()); LRCalc->calculate(LI, MRI->shouldTrackSubRegLiveness(LI.reg)); - computeDeadValues(LI, nullptr); + + if (computeDeadValues(LI, nullptr)) { + SmallVector<LiveInterval *, 4> SplitIntervals; + splitSeparateComponents(LI, SplitIntervals); + } } void LiveIntervals::computeVirtRegs() { @@ -500,6 +504,8 @@ bool LiveIntervals::shrinkToUses(LiveInterval *li, bool LiveIntervals::computeDeadValues(LiveInterval &LI, SmallVectorImpl<MachineInstr*> *dead) { bool MayHaveSplitComponents = false; + bool HaveDeadDef = false; + for (VNInfo *VNI : LI.valnos) { if (VNI->isUnused()) continue; @@ -530,6 +536,10 @@ bool LiveIntervals::computeDeadValues(LiveInterval &LI, MachineInstr *MI = getInstructionFromIndex(Def); assert(MI && "No instruction defining live value"); MI->addRegisterDead(LI.reg, TRI); + if (HaveDeadDef) + MayHaveSplitComponents = true; + HaveDeadDef = true; + if (dead && MI->allDefsAreDead()) { LLVM_DEBUG(dbgs() << "All defs dead: " << Def << '\t' << *MI); dead->push_back(MI); diff --git a/llvm/test/CodeGen/AMDGPU/live-intervals-multiple-dead-defs.mir b/llvm/test/CodeGen/AMDGPU/live-intervals-multiple-dead-defs.mir new file mode 100644 index 00000000000..4c402d7be63 --- /dev/null +++ b/llvm/test/CodeGen/AMDGPU/live-intervals-multiple-dead-defs.mir @@ -0,0 +1,18 @@ +# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py +# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx906 -verify-machineinstrs -run-pass=machine-scheduler -verify-misched -o - %s | FileCheck %s + +# There are multiple dead defs of the same virtual register. Make sure +# the intervals are split during the initial live range computation. + +--- +name: multiple_connected_components_dead +tracksRegLiveness: true +body: | + bb.0: + ; CHECK-LABEL: name: multiple_connected_components_dead + ; CHECK: dead %1:vgpr_32 = V_MOV_B32_e32 0, implicit $exec + ; CHECK: dead %0:vgpr_32 = V_MOV_B32_e32 1, implicit $exec + dead %0:vgpr_32 = V_MOV_B32_e32 0, implicit $exec + dead %0:vgpr_32 = V_MOV_B32_e32 1, implicit $exec + +... |
