[llvm] r365497 - [HardwareLoops] NFC - move hardware loop checking code to isHardwareLoopProfitable()
Chen Zheng via llvm-commits
llvm-commits at lists.llvm.org
Tue Jul 9 07:56:17 PDT 2019
Author: shchenz
Date: Tue Jul 9 07:56:17 2019
New Revision: 365497
URL: http://llvm.org/viewvc/llvm-project?rev=365497&view=rev
Log:
[HardwareLoops] NFC - move hardware loop checking code to isHardwareLoopProfitable()
Differential Revision: https://reviews.llvm.org/D64197
Modified:
llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h
llvm/trunk/lib/Analysis/TargetTransformInfo.cpp
llvm/trunk/lib/CodeGen/HardwareLoops.cpp
Modified: llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h?rev=365497&r1=365496&r2=365497&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h (original)
+++ llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h Tue Jul 9 07:56:17 2019
@@ -99,7 +99,8 @@ struct HardwareLoopInfo {
// produces an i1 to guard the loop entry.
bool isHardwareLoopCandidate(ScalarEvolution &SE, LoopInfo &LI,
DominatorTree &DT, bool ForceNestedLoop = false,
- bool ForceHardwareLoopPHI = false);
+ bool ForceHardwareLoopPHI = false,
+ bool ForceGuardLoopEntry = false);
bool canAnalyze(LoopInfo &LI);
};
Modified: llvm/trunk/lib/Analysis/TargetTransformInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/TargetTransformInfo.cpp?rev=365497&r1=365496&r2=365497&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/TargetTransformInfo.cpp (original)
+++ llvm/trunk/lib/Analysis/TargetTransformInfo.cpp Tue Jul 9 07:56:17 2019
@@ -20,6 +20,9 @@
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/LoopIterator.h"
+#include "llvm/Transforms/Utils.h"
+#include "llvm/Transforms/Utils/LoopUtils.h"
+#include "llvm/Analysis/ScalarEvolutionExpander.h"
#include <utility>
using namespace llvm;
@@ -55,7 +58,8 @@ bool HardwareLoopInfo::canAnalyze(LoopIn
bool HardwareLoopInfo::isHardwareLoopCandidate(ScalarEvolution &SE,
LoopInfo &LI, DominatorTree &DT,
bool ForceNestedLoop,
- bool ForceHardwareLoopPHI) {
+ bool ForceHardwareLoopPHI,
+ bool ForceGuardLoopEntry) {
SmallVector<BasicBlock *, 4> ExitingBlocks;
L->getExitingBlocks(ExitingBlocks);
@@ -134,6 +138,33 @@ bool HardwareLoopInfo::isHardwareLoopCan
if (!ExitBlock)
return false;
+
+ BasicBlock *Preheader = L->getLoopPreheader();
+
+ // If we don't have a preheader, then insert one.
+ if (!Preheader)
+ Preheader = InsertPreheaderForLoop(L, &DT, &LI, nullptr, true);
+ if (!Preheader)
+ return false;
+
+ // Make sure we have a valid Loop Count
+ if (!ExitCount->getType()->isPointerTy() && ExitCount->getType() != CountType)
+ ExitCount = SE.getZeroExtendExpr(ExitCount, CountType);
+
+ ExitCount = SE.getAddExpr(ExitCount, SE.getOne(CountType));
+
+ BasicBlock *BB = L->getLoopPreheader();
+
+ if (ForceGuardLoopEntry && BB->getSinglePredecessor() &&
+ cast<BranchInst>(BB->getTerminator())->isUnconditional())
+ BB = BB->getSinglePredecessor();
+
+ if (!isSafeToExpandAt(ExitCount, BB->getTerminator(), SE)) {
+ LLVM_DEBUG(dbgs() << "Not a Hardware Loop: unsafe to expand ExitCount "
+ << *ExitCount << "\n");
+ return false;
+ }
+
return true;
}
Modified: llvm/trunk/lib/CodeGen/HardwareLoops.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/HardwareLoops.cpp?rev=365497&r1=365496&r2=365497&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/HardwareLoops.cpp (original)
+++ llvm/trunk/lib/CodeGen/HardwareLoops.cpp Tue Jul 9 07:56:17 2019
@@ -15,7 +15,6 @@
///
//===----------------------------------------------------------------------===//
-#include "llvm/Pass.h"
#include "llvm/PassRegistry.h"
#include "llvm/PassSupport.h"
#include "llvm/ADT/Statistic.h"
@@ -36,10 +35,8 @@
#include "llvm/IR/Value.h"
#include "llvm/Support/Debug.h"
#include "llvm/Transforms/Scalar.h"
-#include "llvm/Transforms/Utils.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/Transforms/Utils/LoopUtils.h"
#define DEBUG_TYPE "hardware-loops"
@@ -112,7 +109,6 @@ namespace {
const DataLayout *DL = nullptr;
const TargetTransformInfo *TTI = nullptr;
DominatorTree *DT = nullptr;
- bool PreserveLCSSA = false;
AssumptionCache *AC = nullptr;
TargetLibraryInfo *LibInfo = nullptr;
Module *M = nullptr;
@@ -184,7 +180,6 @@ bool HardwareLoops::runOnFunction(Functi
DL = &F.getParent()->getDataLayout();
auto *TLIP = getAnalysisIfAvailable<TargetLibraryInfoWrapperPass>();
LibInfo = TLIP ? &TLIP->getTLI() : nullptr;
- PreserveLCSSA = mustPreserveAnalysisID(LCSSAID);
AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
M = F.getParent();
@@ -230,25 +225,19 @@ bool HardwareLoops::TryConvertLoop(Loop
bool HardwareLoops::TryConvertLoop(HardwareLoopInfo &HWLoopInfo) {
- Loop *L = HWLoopInfo.L;
- LLVM_DEBUG(dbgs() << "HWLoops: Try to convert profitable loop: " << *L);
+ LLVM_DEBUG(dbgs() << "HWLoops: Try to convert profitable loop: "
+ << *HWLoopInfo.L);
if (!HWLoopInfo.isHardwareLoopCandidate(*SE, *LI, *DT, ForceNestedLoop,
- ForceHardwareLoopPHI))
+ ForceHardwareLoopPHI,
+ ForceGuardLoopEntry))
return false;
assert(
(HWLoopInfo.ExitBlock && HWLoopInfo.ExitBranch && HWLoopInfo.ExitCount) &&
"Hardware Loop must have set exit info.");
- BasicBlock *Preheader = L->getLoopPreheader();
-
- // If we don't have a preheader, then insert one.
- if (!Preheader)
- Preheader = InsertPreheaderForLoop(L, DT, LI, nullptr, PreserveLCSSA);
- if (!Preheader)
- return false;
-
+ // Now start to converting...
HardwareLoop HWLoop(HWLoopInfo, *SE, *DL);
HWLoop.Create();
++NumHWLoops;
@@ -257,10 +246,10 @@ bool HardwareLoops::TryConvertLoop(Hardw
void HardwareLoop::Create() {
LLVM_DEBUG(dbgs() << "HWLoops: Converting loop..\n");
-
+
Value *LoopCountInit = InitLoopCount();
- if (!LoopCountInit)
- return;
+
+ assert(LoopCountInit && "Hardware Loop must have a loop count");
InsertIterationSetup(LoopCountInit);
@@ -320,32 +309,22 @@ Value *HardwareLoop::InitLoopCount() {
// loop counter and tests that is not zero?
SCEVExpander SCEVE(SE, DL, "loopcnt");
- if (!ExitCount->getType()->isPointerTy() &&
- ExitCount->getType() != CountType)
- ExitCount = SE.getZeroExtendExpr(ExitCount, CountType);
-
- ExitCount = SE.getAddExpr(ExitCount, SE.getOne(CountType));
// If we're trying to use the 'test and set' form of the intrinsic, we need
// to replace a conditional branch that is controlling entry to the loop. It
// is likely (guaranteed?) that the preheader has an unconditional branch to
// the loop header, so also check if it has a single predecessor.
if (SE.isLoopEntryGuardedByCond(L, ICmpInst::ICMP_NE, ExitCount,
- SE.getZero(ExitCount->getType()))) {
- LLVM_DEBUG(dbgs() << " - Attempting to use test.set counter.\n");
+ SE.getZero(ExitCount->getType())))
UseLoopGuard |= ForceGuardLoopEntry;
- } else
+ else
UseLoopGuard = false;
BasicBlock *BB = L->getLoopPreheader();
if (UseLoopGuard && BB->getSinglePredecessor() &&
- cast<BranchInst>(BB->getTerminator())->isUnconditional())
+ cast<BranchInst>(BB->getTerminator())->isUnconditional()) {
+ LLVM_DEBUG(dbgs() << " - Attempting to use test.set counter.\n");
BB = BB->getSinglePredecessor();
-
- if (!isSafeToExpandAt(ExitCount, BB->getTerminator(), SE)) {
- LLVM_DEBUG(dbgs() << "- Bailing, unsafe to expand ExitCount "
- << *ExitCount << "\n");
- return nullptr;
}
Value *Count = SCEVE.expandCodeFor(ExitCount, CountType,
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