[llvm] e0e5c64 - [SDAG] Don't require LazyBlockFrequencyInfo at optnone

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2020-05-28T18:48:33+02:00
New Revision: e0e5c644607ad71888c1df0fdbf3331d0fc2559f

URL: https://github.com/llvm/llvm-project/commit/e0e5c644607ad71888c1df0fdbf3331d0fc2559f
DIFF: https://github.com/llvm/llvm-project/commit/e0e5c644607ad71888c1df0fdbf3331d0fc2559f.diff

LOG: [SDAG] Don't require LazyBlockFrequencyInfo at optnone

While LazyBlockFrequencyInfo itself is lazy, the dominator tree
and loop info analyses it requires are not. Drop the dependency
on this pass in SelectionDAGIsel at O0.
This makes for a ~0.6% O0 compile-time improvement.

Differential Revision: https://reviews.llvm.org/D80387

Added: 
    

Modified: 
    llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
    llvm/test/CodeGen/AArch64/O0-pipeline.ll
    llvm/test/CodeGen/X86/O0-pipeline.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index a0cfd3eb729f..d2fac644d902 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -337,7 +337,8 @@ void SelectionDAGISel::getAnalysisUsage(AnalysisUsage &AU) const {
   if (UseMBPI && OptLevel != CodeGenOpt::None)
     AU.addRequired<BranchProbabilityInfoWrapperPass>();
   AU.addRequired<ProfileSummaryInfoWrapperPass>();
-  LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AU);
+  if (OptLevel != CodeGenOpt::None)
+    LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AU);
   MachineFunctionPass::getAnalysisUsage(AU);
 }
 
@@ -441,9 +442,9 @@ bool SelectionDAGISel::runOnMachineFunction(MachineFunction &mf) {
   auto *LIWP = getAnalysisIfAvailable<LoopInfoWrapperPass>();
   LoopInfo *LI = LIWP ? &LIWP->getLoopInfo() : nullptr;
   auto *PSI = &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI();
-  auto *BFI = (PSI && PSI->hasProfileSummary()) ?
-              &getAnalysis<LazyBlockFrequencyInfoPass>().getBFI() :
-              nullptr;
+  BlockFrequencyInfo *BFI = nullptr;
+  if (PSI && PSI->hasProfileSummary() && OptLevel != CodeGenOpt::None)
+    BFI = &getAnalysis<LazyBlockFrequencyInfoPass>().getBFI();
 
   LLVM_DEBUG(dbgs() << "\n\n\n=== " << Fn.getName() << "\n");
 

diff  --git a/llvm/test/CodeGen/AArch64/O0-pipeline.ll b/llvm/test/CodeGen/AArch64/O0-pipeline.ll
index 23d66af605cf..a1141e2255e6 100644
--- a/llvm/test/CodeGen/AArch64/O0-pipeline.ll
+++ b/llvm/test/CodeGen/AArch64/O0-pipeline.ll
@@ -42,10 +42,6 @@
 ; CHECK-NEXT:       Analysis for ComputingKnownBits
 ; CHECK-NEXT:       InstructionSelect
 ; CHECK-NEXT:       ResetMachineFunction
-; CHECK-NEXT:       Dominator Tree Construction
-; CHECK-NEXT:       Natural Loop Information
-; CHECK-NEXT:       Lazy Branch Probability Analysis
-; CHECK-NEXT:       Lazy Block Frequency Analysis
 ; CHECK-NEXT:       AArch64 Instruction Selection
 ; CHECK-NEXT:       Finalize ISel and expand pseudo-instructions
 ; CHECK-NEXT:       Local Stack Slot Allocation

diff  --git a/llvm/test/CodeGen/X86/O0-pipeline.ll b/llvm/test/CodeGen/X86/O0-pipeline.ll
index e2e3437e2cbd..6d94bc163a0f 100644
--- a/llvm/test/CodeGen/X86/O0-pipeline.ll
+++ b/llvm/test/CodeGen/X86/O0-pipeline.ll
@@ -33,10 +33,6 @@
 ; CHECK-NEXT:       Safe Stack instrumentation pass
 ; CHECK-NEXT:       Insert stack protectors
 ; CHECK-NEXT:       Module Verifier
-; CHECK-NEXT:       Dominator Tree Construction
-; CHECK-NEXT:       Natural Loop Information
-; CHECK-NEXT:       Lazy Branch Probability Analysis
-; CHECK-NEXT:       Lazy Block Frequency Analysis
 ; CHECK-NEXT:       X86 DAG->DAG Instruction Selection
 ; CHECK-NEXT:       X86 PIC Global Base Reg Initialization
 ; CHECK-NEXT:       Finalize ISel and expand pseudo-instructions