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-rw-r--r--llvm/lib/Target/PowerPC/CMakeLists.txt1
-rw-r--r--llvm/lib/Target/PowerPC/PPC.h2
-rw-r--r--llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp253
-rw-r--r--llvm/lib/Target/PowerPC/PPCTargetMachine.cpp5
-rw-r--r--llvm/test/CodeGen/PowerPC/BoolRetToIntTest.ll203
5 files changed, 464 insertions, 0 deletions
diff --git a/llvm/lib/Target/PowerPC/CMakeLists.txt b/llvm/lib/Target/PowerPC/CMakeLists.txt
index df6e08db8d3..c31ababafbe 100644
--- a/llvm/lib/Target/PowerPC/CMakeLists.txt
+++ b/llvm/lib/Target/PowerPC/CMakeLists.txt
@@ -13,6 +13,7 @@ tablegen(LLVM PPCGenSubtargetInfo.inc -gen-subtarget)
add_public_tablegen_target(PowerPCCommonTableGen)
add_llvm_target(PowerPCCodeGen
+ PPCBoolRetToInt.cpp
PPCAsmPrinter.cpp
PPCBranchSelector.cpp
PPCCTRLoops.cpp
diff --git a/llvm/lib/Target/PowerPC/PPC.h b/llvm/lib/Target/PowerPC/PPC.h
index e157fd37c6e..a259ed3fd32 100644
--- a/llvm/lib/Target/PowerPC/PPC.h
+++ b/llvm/lib/Target/PowerPC/PPC.h
@@ -45,10 +45,12 @@ namespace llvm {
FunctionPass *createPPCBranchSelectionPass();
FunctionPass *createPPCISelDag(PPCTargetMachine &TM);
FunctionPass *createPPCTLSDynamicCallPass();
+ FunctionPass *createPPCBoolRetToIntPass();
void LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI,
AsmPrinter &AP, bool isDarwin);
void initializePPCVSXFMAMutatePass(PassRegistry&);
+ void initializePPCBoolRetToIntPass(PassRegistry&);
extern char &PPCVSXFMAMutateID;
namespace PPCII {
diff --git a/llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp b/llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp
new file mode 100644
index 00000000000..7920240bc2b
--- /dev/null
+++ b/llvm/lib/Target/PowerPC/PPCBoolRetToInt.cpp
@@ -0,0 +1,253 @@
+//===- PPCBoolRetToInt.cpp - Convert bool literals to i32 if they are returned ==//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements converting i1 values to i32 if they could be more
+// profitably allocated as GPRs rather than CRs. This pass will become totally
+// unnecessary if Register Bank Allocation and Global Instruction Selection ever
+// go upstream.
+//
+// Presently, the pass converts i1 Constants, and Arguments to i32 if the
+// transitive closure of their uses includes only PHINodes, CallInsts, and
+// ReturnInsts. The rational is that arguments are generally passed and returned
+// in GPRs rather than CRs, so casting them to i32 at the LLVM IR level will
+// actually save casts at the Machine Instruction level.
+//
+// It might be useful to expand this pass to add bit-wise operations to the list
+// of safe transitive closure types. Also, we miss some opportunities when LLVM
+// represents logical AND and OR operations with control flow rather than data
+// flow. For example by lowering the expression: return (A && B && C)
+//
+// as: return A ? true : B && C.
+//
+// There's code in SimplifyCFG that code be used to turn control flow in data
+// flow using SelectInsts. Selects are slow on some architectures (P7/P8), so
+// this probably isn't good in general, but for the special case of i1, the
+// Selects could be further lowered to bit operations that are fast everywhere.
+//
+//===----------------------------------------------------------------------===//
+
+#include "PPC.h"
+#include "llvm/Transforms/Scalar.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Pass.h"
+
+using namespace llvm;
+
+namespace {
+
+#define DEBUG_TYPE "bool-ret-to-int"
+
+STATISTIC(NumBoolRetPromotion,
+ "Number of times a bool feeding a RetInst was promoted to an int");
+STATISTIC(NumBoolCallPromotion,
+ "Number of times a bool feeding a CallInst was promoted to an int");
+STATISTIC(NumBoolToIntPromotion,
+ "Total number of times a bool was promoted to an int");
+
+class PPCBoolRetToInt : public FunctionPass {
+
+ static SmallPtrSet<Value *, 8> findAllDefs(Value *V) {
+ SmallPtrSet<Value *, 8> Defs;
+ SmallVector<Value *, 8> WorkList;
+ WorkList.push_back(V);
+ Defs.insert(V);
+ while (!WorkList.empty()) {
+ Value *Curr = WorkList.back();
+ WorkList.pop_back();
+ if (User *CurrUser = dyn_cast<User>(Curr))
+ for (auto &Op : CurrUser->operands())
+ if (Defs.insert(Op).second)
+ WorkList.push_back(Op);
+ }
+ return Defs;
+ }
+
+ // Translate a i1 value to an equivalent i32 value:
+ static Value *translate(Value *V) {
+ Type *Int32Ty = Type::getInt32Ty(V->getContext());
+ if (Constant *C = dyn_cast<Constant>(V))
+ return ConstantExpr::getZExt(C, Int32Ty);
+ if (PHINode *P = dyn_cast<PHINode>(V)) {
+ // Temporarily set the operands to 0. We'll fix this later in
+ // runOnUse.
+ Value *Zero = Constant::getNullValue(Int32Ty);
+ PHINode *Q =
+ PHINode::Create(Int32Ty, P->getNumIncomingValues(), P->getName(), P);
+ for (unsigned i = 0; i < P->getNumOperands(); ++i)
+ Q->addIncoming(Zero, P->getIncomingBlock(i));
+ return Q;
+ }
+
+ Argument *A = dyn_cast<Argument>(V);
+ Instruction *I = dyn_cast<Instruction>(V);
+ assert((A || I) && "Unknown value type");
+
+ auto InstPt =
+ A ? &*A->getParent()->getEntryBlock().begin() : I->getNextNode();
+ return new ZExtInst(V, Int32Ty, "", InstPt);
+ }
+
+ typedef SmallPtrSet<const PHINode *, 8> PHINodeSet;
+
+ // A PHINode is Promotable if:
+ // 1. Its type is i1 AND
+ // 2. All of its uses are ReturnInt, CallInst, PHINode, or DbgInfoIntrinsic
+ // AND
+ // 3. All of its operands are Constant or Argument or
+ // CallInst or PHINode AND
+ // 4. All of its PHINode uses are Promotable AND
+ // 5. All of its PHINode operands are Promotable
+ static PHINodeSet getPromotablePHINodes(const Function &F) {
+ PHINodeSet Promotable;
+ // Condition 1
+ for (auto &BB : F)
+ for (auto &I : BB)
+ if (const PHINode *P = dyn_cast<PHINode>(&I))
+ if (P->getType()->isIntegerTy(1))
+ Promotable.insert(P);
+
+ SmallVector<const PHINode *, 8> ToRemove;
+ for (const auto &P : Promotable) {
+ // Condition 2 and 3
+ auto IsValidUser = [] (const Value *V) -> bool {
+ return isa<ReturnInst>(V) || isa<CallInst>(V) || isa<PHINode>(V) ||
+ isa<DbgInfoIntrinsic>(V);
+ };
+ auto IsValidOperand = [] (const Value *V) -> bool {
+ return isa<Constant>(V) || isa<Argument>(V) || isa<CallInst>(V) ||
+ isa<PHINode>(V);
+ };
+ const auto &Users = P->users();
+ const auto &Operands = P->operands();
+ if (!std::all_of(Users.begin(), Users.end(), IsValidUser) ||
+ !std::all_of(Operands.begin(), Operands.end(), IsValidOperand))
+ ToRemove.push_back(P);
+ }
+
+ // Iterate to convergence
+ auto IsPromotable = [&Promotable] (const Value *V) -> bool {
+ const PHINode *Phi = dyn_cast<PHINode>(V);
+ return !Phi || Promotable.count(Phi);
+ };
+ while (!ToRemove.empty()) {
+ for (auto &User : ToRemove)
+ Promotable.erase(User);
+ ToRemove.clear();
+
+ for (const auto &P : Promotable) {
+ // Condition 4 and 5
+ const auto &Users = P->users();
+ const auto &Operands = P->operands();
+ if (!std::all_of(Users.begin(), Users.end(), IsPromotable) ||
+ !std::all_of(Operands.begin(), Operands.end(), IsPromotable))
+ ToRemove.push_back(P);
+ }
+ }
+
+ return Promotable;
+ }
+
+ typedef DenseMap<Value *, Value *> B2IMap;
+
+ public:
+ static char ID;
+ PPCBoolRetToInt() : FunctionPass(ID) {
+ initializePPCBoolRetToIntPass(*PassRegistry::getPassRegistry());
+ }
+
+ bool runOnFunction(Function &F) {
+ PHINodeSet PromotablePHINodes = getPromotablePHINodes(F);
+ B2IMap Bool2IntMap;
+ bool Changed = false;
+ for (auto &BB : F) {
+ for (auto &I : BB) {
+ if (ReturnInst *R = dyn_cast<ReturnInst>(&I))
+ if (F.getReturnType()->isIntegerTy(1))
+ Changed |=
+ runOnUse(R->getOperandUse(0), PromotablePHINodes, Bool2IntMap);
+
+ if (CallInst *CI = dyn_cast<CallInst>(&I))
+ for (auto &U : CI->operands())
+ if (U->getType()->isIntegerTy(1))
+ Changed |= runOnUse(U, PromotablePHINodes, Bool2IntMap);
+ }
+ }
+
+ return Changed;
+ }
+
+ static bool runOnUse(Use &U, const PHINodeSet &PromotablePHINodes,
+ B2IMap &BoolToIntMap) {
+ auto Defs = findAllDefs(U);
+
+ // If the values are all Constants or Arguments, don't bother
+ if (!std::any_of(Defs.begin(), Defs.end(), isa<Instruction, Value *>))
+ return false;
+
+ // Presently, we only know how to handle PHINode, Constant, and Arguments.
+ // Potentially, bitwise operations (AND, OR, XOR, NOT) and sign extension
+ // could also be handled in the future.
+ for (const auto &V : Defs)
+ if (!isa<PHINode>(V) && !isa<Constant>(V) && !isa<Argument>(V))
+ return false;
+
+ for (const auto &V : Defs)
+ if (const PHINode *P = dyn_cast<PHINode>(V))
+ if (!PromotablePHINodes.count(P))
+ return false;
+
+ if (isa<ReturnInst>(U.getUser()))
+ ++NumBoolRetPromotion;
+ if (isa<CallInst>(U.getUser()))
+ ++NumBoolCallPromotion;
+ ++NumBoolToIntPromotion;
+
+ for (const auto &V : Defs)
+ if (!BoolToIntMap.count(V))
+ BoolToIntMap[V] = translate(V);
+
+ // Replace the operands of the translated instructions. There were set to
+ // zero in the translate function.
+ for (auto &Pair : BoolToIntMap) {
+ User *First = dyn_cast<User>(Pair.first);
+ User *Second = dyn_cast<User>(Pair.second);
+ assert((!First || Second) && "translated from user to non-user!?");
+ if (First)
+ for (unsigned i = 0; i < First->getNumOperands(); ++i)
+ Second->setOperand(i, BoolToIntMap[First->getOperand(i)]);
+ }
+
+ Value *IntRetVal = BoolToIntMap[U];
+ Type *Int1Ty = Type::getInt1Ty(U->getContext());
+ Instruction *I = cast<Instruction>(U.getUser());
+ Value *BackToBool = new TruncInst(IntRetVal, Int1Ty, "backToBool", I);
+ U.set(BackToBool);
+
+ return true;
+ }
+
+ void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addPreserved<DominatorTreeWrapperPass>();
+ FunctionPass::getAnalysisUsage(AU);
+ }
+};
+}
+
+char PPCBoolRetToInt::ID = 0;
+INITIALIZE_PASS(PPCBoolRetToInt, "bool-ret-to-int",
+ "Convert i1 constants to i32 if they are returned",
+ false, false)
+
+FunctionPass *llvm::createPPCBoolRetToIntPass() { return new PPCBoolRetToInt(); }
diff --git a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
index 24a9ef0ef07..946e0f10cdd 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
@@ -71,6 +71,9 @@ extern "C" void LLVMInitializePowerPCTarget() {
RegisterTargetMachine<PPC32TargetMachine> A(ThePPC32Target);
RegisterTargetMachine<PPC64TargetMachine> B(ThePPC64Target);
RegisterTargetMachine<PPC64TargetMachine> C(ThePPC64LETarget);
+
+ PassRegistry &PR = *PassRegistry::getPassRegistry();
+ initializePPCBoolRetToIntPass(PR);
}
/// Return the datalayout string of a subtarget.
@@ -286,6 +289,8 @@ TargetPassConfig *PPCTargetMachine::createPassConfig(PassManagerBase &PM) {
}
void PPCPassConfig::addIRPasses() {
+ if (TM->getOptLevel() != CodeGenOpt::None)
+ addPass(createPPCBoolRetToIntPass());
addPass(createAtomicExpandPass(&getPPCTargetMachine()));
// For the BG/Q (or if explicitly requested), add explicit data prefetch
diff --git a/llvm/test/CodeGen/PowerPC/BoolRetToIntTest.ll b/llvm/test/CodeGen/PowerPC/BoolRetToIntTest.ll
new file mode 100644
index 00000000000..a7b79789b4c
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/BoolRetToIntTest.ll
@@ -0,0 +1,203 @@
+; RUN: opt -bool-ret-to-int -S -o - < %s | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-n32:64"
+target triple = "powerpc64le-unknown-linux-gnu"
+
+; CHECK-LABEL: notBoolRet
+define signext i32 @notBoolRet() {
+entry:
+; CHECK: ret i32 1
+ ret i32 1
+}
+
+; CHECK-LABEL: find
+define zeroext i1 @find(i8** readonly %begin, i8** readnone %end, i1 (i8*)* nocapture %hasProp) {
+entry:
+ %cmp.4 = icmp eq i8** %begin, %end
+ br i1 %cmp.4, label %cleanup, label %for.body.preheader
+
+for.body.preheader: ; preds = %entry
+ br label %for.body
+
+for.cond: ; preds = %for.body
+ %cmp = icmp eq i8** %incdec.ptr, %end
+ br i1 %cmp, label %cleanup.loopexit, label %for.body
+
+for.body: ; preds = %for.body.preheader, %for.cond
+ %curr.05 = phi i8** [ %incdec.ptr, %for.cond ], [ %begin, %for.body.preheader ]
+ %0 = load i8*, i8** %curr.05, align 8
+ %call = tail call zeroext i1 %hasProp(i8* %0)
+ %incdec.ptr = getelementptr inbounds i8*, i8** %curr.05, i64 1
+ br i1 %call, label %cleanup.loopexit, label %for.cond
+
+cleanup.loopexit: ; preds = %for.body, %for.cond
+; CHECK: [[PHI:%.+]] = phi i32 [ 1, %for.body ], [ 0, %for.cond ]
+ %cleanup.dest.slot.0.ph = phi i1 [ true, %for.body ], [ false, %for.cond ]
+ br label %cleanup
+
+cleanup: ; preds = %cleanup.loopexit, %entry
+; CHECK: = phi i32 [ 0, %entry ], [ [[PHI]], %cleanup.loopexit ]
+ %cleanup.dest.slot.0 = phi i1 [ false, %entry ], [ %cleanup.dest.slot.0.ph, %cleanup.loopexit ]
+; CHECK: [[REG:%.+]] = trunc i32 {{%.+}} to i1
+; CHECK: ret i1 [[REG]]
+ ret i1 %cleanup.dest.slot.0
+}
+
+; CHECK-LABEL: retFalse
+define zeroext i1 @retFalse() {
+entry:
+; CHECK: ret i1 false
+ ret i1 false
+}
+
+; CHECK-LABEL: retCvtFalse
+define zeroext i1 @retCvtFalse() {
+entry:
+; CHECK: ret i1 false
+ ret i1 trunc(i32 0 to i1)
+}
+
+; CHECK-LABEL: find_cont
+define void @find_cont(i8** readonly %begin, i8** readnone %end, i1 (i8*)* nocapture %hasProp, void (i1)* nocapture %cont) {
+entry:
+ %cmp.4 = icmp eq i8** %begin, %end
+ br i1 %cmp.4, label %cleanup, label %for.body.preheader
+
+for.body.preheader: ; preds = %entry
+ br label %for.body
+
+for.cond: ; preds = %for.body
+ %cmp = icmp eq i8** %incdec.ptr, %end
+ br i1 %cmp, label %cleanup.loopexit, label %for.body
+
+for.body: ; preds = %for.body.preheader, %for.cond
+ %curr.05 = phi i8** [ %incdec.ptr, %for.cond ], [ %begin, %for.body.preheader ]
+ %0 = load i8*, i8** %curr.05, align 8
+ %call = tail call zeroext i1 %hasProp(i8* %0)
+ %incdec.ptr = getelementptr inbounds i8*, i8** %curr.05, i64 1
+ br i1 %call, label %cleanup.loopexit, label %for.cond
+
+cleanup.loopexit: ; preds = %for.body, %for.cond
+; CHECK: [[PHI:%.+]] = phi i32 [ 1, %for.body ], [ 0, %for.cond ]
+ %cleanup.dest.slot.0.ph = phi i1 [ true, %for.body ], [ false, %for.cond ]
+ br label %cleanup
+
+cleanup: ; preds = %cleanup.loopexit, %entry
+; CHECK: = phi i32 [ 0, %entry ], [ [[PHI]], %cleanup.loopexit ]
+ %cleanup.dest.slot.0 = phi i1 [ false, %entry ], [ %cleanup.dest.slot.0.ph, %cleanup.loopexit ]
+; CHECK: [[REG:%.+]] = trunc i32 {{%.+}} to i1
+; CHECK: call void %cont(i1 [[REG]]
+ tail call void %cont(i1 %cleanup.dest.slot.0)
+ ret void
+}
+
+; CHECK-LABEL: find_cont_ret
+define zeroext i1 @find_cont_ret(i8** readonly %begin, i8** readnone %end, i1 (i8*)* nocapture %hasProp, void (i1)* nocapture %cont) {
+entry:
+ %cmp.4 = icmp eq i8** %begin, %end
+ br i1 %cmp.4, label %cleanup, label %for.body.preheader
+
+for.body.preheader: ; preds = %entry
+ br label %for.body
+
+for.cond: ; preds = %for.body
+ %cmp = icmp eq i8** %incdec.ptr, %end
+ br i1 %cmp, label %cleanup.loopexit, label %for.body
+
+for.body: ; preds = %for.body.preheader, %for.cond
+ %curr.05 = phi i8** [ %incdec.ptr, %for.cond ], [ %begin, %for.body.preheader ]
+ %0 = load i8*, i8** %curr.05, align 8
+ %call = tail call zeroext i1 %hasProp(i8* %0)
+ %incdec.ptr = getelementptr inbounds i8*, i8** %curr.05, i64 1
+ br i1 %call, label %cleanup.loopexit, label %for.cond
+
+cleanup.loopexit: ; preds = %for.body, %for.cond
+; CHECK: [[PHI:%.+]] = phi i32 [ 1, %for.body ], [ 0, %for.cond ]
+ %cleanup.dest.slot.0.ph = phi i1 [ true, %for.body ], [ false, %for.cond ]
+ br label %cleanup
+
+cleanup: ; preds = %cleanup.loopexit, %entry
+; CHECK: = phi i32 [ 0, %entry ], [ [[PHI]], %cleanup.loopexit ]
+ %cleanup.dest.slot.0 = phi i1 [ false, %entry ], [ %cleanup.dest.slot.0.ph, %cleanup.loopexit ]
+; CHECK: [[REG:%.+]] = trunc i32 {{%.+}} to i1
+; CHECK: call void %cont(i1 [[REG]]
+ tail call void %cont(i1 %cleanup.dest.slot.0)
+; CHECK: [[REG:%.+]] = trunc i32 {{%.+}} to i1
+; CHECK: ret i1 [[REG]]
+ ret i1 %cleanup.dest.slot.0
+}
+
+; CHECK-LABEL: arg_operand
+define zeroext i1 @arg_operand(i1 %operand) {
+entry:
+ br i1 %operand, label %foo, label %cleanup
+
+foo:
+ br label %cleanup
+
+cleanup:
+; CHECK: [[REG:%.+]] = trunc i32 {{%.+}} to i1
+; CHECK: ret i1 [[REG]]
+ %result = phi i1 [ false, %foo ], [ %operand, %entry ]
+ ret i1 %result
+}
+
+; CHECK-LABEL: bad_use
+define zeroext i1 @bad_use(i1 %operand) {
+entry:
+ br i1 %operand, label %foo, label %cleanup
+
+foo:
+ br label %cleanup
+
+cleanup:
+; CHECK: [[REG:%.+]] = phi i1
+; CHECK: ret i1 [[REG]]
+ %result = phi i1 [ false, %foo], [ true, %entry ]
+ %0 = icmp eq i1 %result, %operand
+ ret i1 %result
+}
+
+; CHECK-LABEL: bad_use_closure
+define zeroext i1 @bad_use_closure(i1 %operand) {
+entry:
+ br i1 %operand, label %foo, label %cleanup
+
+foo:
+ %bar = phi i1 [ false, %entry ]
+ %0 = icmp eq i1 %bar, %operand
+ br label %cleanup
+
+cleanup:
+; CHECK: [[REG:%.+]] = phi i1 [ true
+; CHECK: ret i1 [[REG]]
+ %result = phi i1 [ true, %entry ], [ %bar, %foo]
+ ret i1 %result
+}
+
+; CHECK-LABEL: arg_test
+define zeroext i1 @arg_test(i1 %operand) {
+entry:
+ br i1 %operand, label %foo, label %cleanup
+
+foo:
+ %bar = phi i1 [ false, %entry ]
+ br label %cleanup
+
+; CHECK-LABEL: cleanup
+cleanup:
+; CHECK: [[REG:%.+]] = trunc i32 {{%.+}} to i1
+; CHECK: ret i1 [[REG]]
+ %result = phi i1 [ %bar, %foo], [ %operand, %entry ]
+ ret i1 %result
+}
+
+declare zeroext i1 @return_i1()
+
+; CHECK-LABEL: call_test
+define zeroext i1 @call_test() {
+; CHECK: [[REG:%.+]] = call i1
+ %result = call i1 @return_i1()
+; CHECK: ret i1 [[REG]]
+ ret i1 %result
+} \ No newline at end of file
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