void initializeIntervalPartitionPass(PassRegistry&);
void initializeIRTranslatorPass(PassRegistry &);
void initializeJumpThreadingPass(PassRegistry&);
-void initializeLCSSAPass(PassRegistry&);
+void initializeLCSSAWrapperPassPass(PassRegistry &);
void initializeLICMPass(PassRegistry&);
void initializeLazyValueInfoPass(PassRegistry&);
void initializeLintPass(PassRegistry&);
--- /dev/null
+//===- LCSSA.h - Loop-closed SSA transform Pass -----------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass transforms loops by placing phi nodes at the end of the loops for
+// all values that are live across the loop boundary. For example, it turns
+// the left into the right code:
+//
+// for (...) for (...)
+// if (c) if (c)
+// X1 = ... X1 = ...
+// else else
+// X2 = ... X2 = ...
+// X3 = phi(X1, X2) X3 = phi(X1, X2)
+// ... = X3 + 4 X4 = phi(X3)
+// ... = X4 + 4
+//
+// This is still valid LLVM; the extra phi nodes are purely redundant, and will
+// be trivially eliminated by InstCombine. The major benefit of this
+// transformation is that it makes many other loop optimizations, such as
+// LoopUnswitching, simpler.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_UTILS_LCSSA_H
+#define LLVM_TRANSFORMS_UTILS_LCSSA_H
+
+#include "llvm/IR/PassManager.h"
+
+namespace llvm {
+
+/// Converts loops into loop-closed SSA form.
+class LCSSAPass : public PassInfoMixin<LCSSAPass> {
+public:
+ PreservedAnalyses run(Function &F, AnalysisManager<Function> &AM);
+};
+} // end namespace llvm
+
+#endif // LLVM_TRANSFORMS_UTILS_LCSSA_H
#include "llvm/Transforms/Scalar/SROA.h"
#include "llvm/Transforms/Scalar/SimplifyCFG.h"
#include "llvm/Transforms/Scalar/Sink.h"
+#include "llvm/Transforms/Utils/LCSSA.h"
#include "llvm/Transforms/Utils/MemorySSA.h"
#include <type_traits>
FUNCTION_PASS("guard-widening", GuardWideningPass())
FUNCTION_PASS("gvn", GVN())
FUNCTION_PASS("partially-inline-libcalls", PartiallyInlineLibCallsPass())
+FUNCTION_PASS("lcssa", LCSSAPass())
FUNCTION_PASS("print", PrintFunctionPass(dbgs()))
FUNCTION_PASS("print<assumptions>", AssumptionPrinterPass(dbgs()))
FUNCTION_PASS("print<block-freq>", BlockFrequencyPrinterPass(dbgs()))
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
-INITIALIZE_PASS_DEPENDENCY(LCSSA)
+INITIALIZE_PASS_DEPENDENCY(LCSSAWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_END(LoopInterchange, "loop-interchange",
INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(GlobalsAAWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(LCSSA)
+INITIALIZE_PASS_DEPENDENCY(LCSSAWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopAccessAnalysis)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
//
//===----------------------------------------------------------------------===//
-#include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Utils/LCSSA.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/PredIteratorCache.h"
#include "llvm/Pass.h"
+#include "llvm/Transforms/Scalar.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/SSAUpdater.h"
using namespace llvm;
return Changed;
}
+/// Process all loops in the function, inner-most out.
+static bool formLCSSAOnAllLoops(LoopInfo *LI, DominatorTree &DT,
+ ScalarEvolution *SE) {
+ bool Changed = false;
+ for (auto &L : *LI)
+ Changed |= formLCSSARecursively(*L, DT, LI, SE);
+ return Changed;
+}
+
namespace {
-struct LCSSA : public FunctionPass {
+struct LCSSAWrapperPass : public FunctionPass {
static char ID; // Pass identification, replacement for typeid
- LCSSA() : FunctionPass(ID) {
- initializeLCSSAPass(*PassRegistry::getPassRegistry());
+ LCSSAWrapperPass() : FunctionPass(ID) {
+ initializeLCSSAWrapperPassPass(*PassRegistry::getPassRegistry());
}
// Cached analysis information for the current function.
};
}
-char LCSSA::ID = 0;
-INITIALIZE_PASS_BEGIN(LCSSA, "lcssa", "Loop-Closed SSA Form Pass", false, false)
+char LCSSAWrapperPass::ID = 0;
+INITIALIZE_PASS_BEGIN(LCSSAWrapperPass, "lcssa", "Loop-Closed SSA Form Pass",
+ false, false)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
-INITIALIZE_PASS_END(LCSSA, "lcssa", "Loop-Closed SSA Form Pass", false, false)
-
-Pass *llvm::createLCSSAPass() { return new LCSSA(); }
-char &llvm::LCSSAID = LCSSA::ID;
+INITIALIZE_PASS_END(LCSSAWrapperPass, "lcssa", "Loop-Closed SSA Form Pass",
+ false, false)
+Pass *llvm::createLCSSAPass() { return new LCSSAWrapperPass(); }
+char &llvm::LCSSAID = LCSSAWrapperPass::ID;
-/// Process all loops in the function, inner-most out.
-bool LCSSA::runOnFunction(Function &F) {
- bool Changed = false;
+/// Transform \p F into loop-closed SSA form.
+bool LCSSAWrapperPass::runOnFunction(Function &F) {
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
auto *SEWP = getAnalysisIfAvailable<ScalarEvolutionWrapperPass>();
SE = SEWP ? &SEWP->getSE() : nullptr;
- // Simplify each loop nest in the function.
- for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
- Changed |= formLCSSARecursively(**I, *DT, LI, SE);
-
- return Changed;
+ return formLCSSAOnAllLoops(LI, *DT, SE);
}
+PreservedAnalyses LCSSAPass::run(Function &F, AnalysisManager<Function> &AM) {
+ auto &LI = AM.getResult<LoopAnalysis>(F);
+ auto &DT = AM.getResult<DominatorTreeAnalysis>(F);
+ auto *SE = AM.getCachedResult<ScalarEvolutionAnalysis>(F);
+ if (!formLCSSAOnAllLoops(&LI, DT, SE))
+ return PreservedAnalyses::all();
+
+ // FIXME: There is no setPreservesCFG in the new PM. When that becomes
+ // available, it should be used here.
+ PreservedAnalyses PA;
+ PA.preserve<BasicAA>();
+ PA.preserve<GlobalsAA>();
+ PA.preserve<SCEVAA>();
+ PA.preserve<ScalarEvolutionAnalysis>();
+ return PA;
+}
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
- INITIALIZE_PASS_DEPENDENCY(LCSSA)
+ INITIALIZE_PASS_DEPENDENCY(LCSSAWrapperPass)
INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
INITIALIZE_PASS_DEPENDENCY(BasicAAWrapperPass)
INITIALIZE_PASS_DEPENDENCY(GlobalsAAWrapperPass)
initializeAddDiscriminatorsPass(Registry);
initializeBreakCriticalEdgesPass(Registry);
initializeInstNamerPass(Registry);
- initializeLCSSAPass(Registry);
+ initializeLCSSAWrapperPassPass(Registry);
initializeLoopSimplifyPass(Registry);
initializeLowerInvokePass(Registry);
initializeLowerSwitchPass(Registry);
INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(LCSSA)
+INITIALIZE_PASS_DEPENDENCY(LCSSAWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
INITIALIZE_PASS_DEPENDENCY(LoopAccessAnalysis)
; RUN: opt < %s -lcssa -S | FileCheck %s
+; RUN: opt < %s -passes=lcssa -S | FileCheck %s
declare i1 @c1()
; RUN: opt < %s -lcssa
+; RUN: opt < %s -passes=lcssa
%struct.SetJmpMapEntry = type { i8*, i32, %struct.SetJmpMapEntry* }
; RUN: opt < %s -lcssa -disable-output
+; RUN: opt < %s -passes=lcssa -disable-output
; PR977
; END.
; RUN: opt < %s -lcssa -S | FileCheck %s
+; RUN: opt < %s -passes=lcssa -S | FileCheck %s
define void @lcssa(i1 %S2) {
; CHECK-LABEL: @lcssa
; RUN: opt < %s -lcssa
+; RUN: opt < %s -passes=lcssa
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32"
; RUN: opt -lcssa -S < %s | FileCheck %s
+; RUN: opt -passes=lcssa -S < %s | FileCheck %s
; This test is based on the following C++ code:
;
; RUN: opt < %s -lcssa -S | FileCheck %s
+; RUN: opt < %s -passes=lcssa -S | FileCheck %s
; CHECK: exit1:
; CHECK: .lcssa =
; CHECK: exit2: