From dcc4436cddc9b5d155040ed3ed38e9070ec4e3b8 Mon Sep 17 00:00:00 2001 From: Jakob Stoklund Olesen Date: Fri, 3 Aug 2012 22:12:54 +0000 Subject: [PATCH] Add an experimental -early-live-intervals option. This option runs LiveIntervals before TwoAddressInstructionPass which will eventually learn to exploit and update the analysis. Eventually, LiveIntervals will run before PHIElimination, and we can get rid of LiveVariables. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161270 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/CodeGen/Passes.h | 4 ++++ lib/CodeGen/LiveIntervalAnalysis.cpp | 1 + lib/CodeGen/Passes.cpp | 9 +++++++++ 3 files changed, 14 insertions(+) diff --git a/include/llvm/CodeGen/Passes.h b/include/llvm/CodeGen/Passes.h index 0cddff8d9da..07b3b45873a 100644 --- a/include/llvm/CodeGen/Passes.h +++ b/include/llvm/CodeGen/Passes.h @@ -315,6 +315,10 @@ namespace llvm { /// This pass is still in development extern char &StrongPHIEliminationID; + /// LiveIntervals - This analysis keeps track of the live ranges of virtual + /// and physical registers. + extern char &LiveIntervalsID; + /// LiveStacks pass. An analysis keeping track of the liveness of stack slots. extern char &LiveStacksID; diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp index b488e8f077e..d0f8ae1af30 100644 --- a/lib/CodeGen/LiveIntervalAnalysis.cpp +++ b/lib/CodeGen/LiveIntervalAnalysis.cpp @@ -45,6 +45,7 @@ NewLiveIntervals("new-live-intervals", cl::Hidden, cl::desc("Use new algorithm forcomputing live intervals")); char LiveIntervals::ID = 0; +char &llvm::LiveIntervalsID = LiveIntervals::ID; INITIALIZE_PASS_BEGIN(LiveIntervals, "liveintervals", "Live Interval Analysis", false, false) INITIALIZE_AG_DEPENDENCY(AliasAnalysis) diff --git a/lib/CodeGen/Passes.cpp b/lib/CodeGen/Passes.cpp index 69d6d00091a..cfa3eecf02e 100644 --- a/lib/CodeGen/Passes.cpp +++ b/lib/CodeGen/Passes.cpp @@ -88,6 +88,10 @@ PrintMachineInstrs("print-machineinstrs", cl::ValueOptional, cl::desc("Print machine instrs"), cl::value_desc("pass-name"), cl::init("option-unspecified")); +// Experimental option to run live inteerval analysis early. +static cl::opt EarlyLiveIntervals("early-live-intervals", cl::Hidden, + cl::desc("Run live interval analysis earlier in the pipeline")); + /// Allow standard passes to be disabled by command line options. This supports /// simple binary flags that either suppress the pass or do nothing. /// i.e. -disable-mypass=false has no effect. @@ -648,6 +652,11 @@ void TargetPassConfig::addOptimizedRegAlloc(FunctionPass *RegAllocPass) { addPass(&MachineLoopInfoID); addPass(&PHIEliminationID); } + + // Eventually, we want to run LiveIntervals before PHI elimination. + if (EarlyLiveIntervals) + addPass(&LiveIntervalsID); + addPass(&TwoAddressInstructionPassID); if (EnableStrongPHIElim)