[llvm] r304517 - [Profile] Enhance expect lowering to handle correlated branches

Xinliang David Li via llvm-commits llvm-commits at lists.llvm.org
Wed Jun 7 10:29:06 PDT 2017


Fix is on the way.

David

On Wed, Jun 7, 2017 at 10:12 AM, Greg Bedwell <gregbedwell at gmail.com> wrote:

> Hi,
>
> We spotted a new assertion failure starting with this commit (sorry it
> took a few days to spot and report).  I've put details in:
> https://bugs.llvm.org/show_bug.cgi?id=33346
>
> -Greg
>
>
> On 2 June 2017 at 03:09, Xinliang David Li via llvm-commits <
> llvm-commits at lists.llvm.org> wrote:
>
>> Author: davidxl
>> Date: Thu Jun  1 21:09:31 2017
>> New Revision: 304517
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=304517&view=rev
>> Log:
>> [Profile] Enhance expect lowering to handle correlated branches
>>
>> builtin_expect applied on && or || expressions were not
>> handled properly before. With this patch, the problem is fixed.
>>
>> Differential Revision: http://reviews.llvm.org/D33164
>>
>> Added:
>>     llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_merge.ll
>>     llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_or.ll
>>     llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_tern.ll
>> Modified:
>>     llvm/trunk/lib/Transforms/Scalar/LowerExpectIntrinsic.cpp
>>
>> Modified: llvm/trunk/lib/Transforms/Scalar/LowerExpectIntrinsic.cpp
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transform
>> s/Scalar/LowerExpectIntrinsic.cpp?rev=304517&r1=304516&r2=
>> 304517&view=diff
>> ============================================================
>> ==================
>> --- llvm/trunk/lib/Transforms/Scalar/LowerExpectIntrinsic.cpp (original)
>> +++ llvm/trunk/lib/Transforms/Scalar/LowerExpectIntrinsic.cpp Thu Jun  1
>> 21:09:31 2017
>> @@ -14,6 +14,7 @@
>>  #include "llvm/Transforms/Scalar/LowerExpectIntrinsic.h"
>>  #include "llvm/ADT/SmallVector.h"
>>  #include "llvm/ADT/Statistic.h"
>> +#include "llvm/ADT/iterator_range.h"
>>  #include "llvm/IR/BasicBlock.h"
>>  #include "llvm/IR/Constants.h"
>>  #include "llvm/IR/Function.h"
>> @@ -83,6 +84,149 @@ static bool handleSwitchExpect(SwitchIns
>>    return true;
>>  }
>>
>> +/// Handler for PHINodes that define the value argument to an
>> +/// @llvm.expect call.
>> +///
>> +/// If the operand of the phi has a constant value and it 'contradicts'
>> +/// with the expected value of phi def, then the corresponding incoming
>> +/// edge of the phi is unlikely to be taken. Using that information,
>> +/// the branch probability info for the originating branch can be
>> inferred.
>> +static void handlePhiDef(CallInst *Expect) {
>> +  Value &Arg = *Expect->getArgOperand(0);
>> +  ConstantInt *ExpectedValue = cast<ConstantInt>(Expect->getA
>> rgOperand(1));
>> +  const APInt &ExpectedPhiValue = ExpectedValue->getValue();
>> +
>> +  // Walk up in backward a list of instructions that
>> +  // have 'copy' semantics by 'stripping' the copies
>> +  // until a PHI node or an instruction of unknown kind
>> +  // is reached. Negation via xor is also handled.
>> +  //
>> +  //       C = PHI(...);
>> +  //       B = C;
>> +  //       A = B;
>> +  //       D = __builtin_expect(A, 0);
>> +  //
>> +  Value *V = &Arg;
>> +  SmallVector<Instruction *, 4> Operations;
>> +  while (!isa<PHINode>(V)) {
>> +    if (ZExtInst *ZExt = dyn_cast<ZExtInst>(V)) {
>> +      V = ZExt->getOperand(0);
>> +      Operations.push_back(ZExt);
>> +      continue;
>> +    }
>> +
>> +    if (SExtInst *SExt = dyn_cast<SExtInst>(V)) {
>> +      V = SExt->getOperand(0);
>> +      Operations.push_back(SExt);
>> +      continue;
>> +    }
>> +
>> +    BinaryOperator *BinOp = dyn_cast<BinaryOperator>(V);
>> +    if (!BinOp || BinOp->getOpcode() != Instruction::Xor)
>> +      return;
>> +
>> +    ConstantInt *CInt = dyn_cast<ConstantInt>(BinOp->getOperand(1));
>> +    if (!CInt)
>> +      return;
>> +
>> +    V = BinOp->getOperand(0);
>> +    Operations.push_back(BinOp);
>> +  }
>> +
>> +  // Executes the recorded operations on input 'Value'.
>> +  auto ApplyOperations = [&](const APInt &Value) {
>> +    APInt Result = Value;
>> +    for (auto Op : llvm::reverse(Operations)) {
>> +      switch (Op->getOpcode()) {
>> +      case Instruction::Xor:
>> +        Result ^= cast<ConstantInt>(Op->getOperand(1))->getValue();
>> +        break;
>> +      case Instruction::ZExt:
>> +        Result = Result.zext(Op->getType()->getIntegerBitWidth());
>> +        break;
>> +      case Instruction::SExt:
>> +        Result = Result.sext(Op->getType()->getIntegerBitWidth());
>> +        break;
>> +      default:
>> +        llvm_unreachable("Unexpected operation");
>> +      }
>> +    }
>> +    return Result;
>> +  };
>> +
>> +  auto *PhiDef = dyn_cast<PHINode>(V);
>> +
>> +  // Get the first dominating conditional branch of the operand
>> +  // i's incoming block.
>> +  auto GetDomConditional = [&](unsigned i) -> BranchInst * {
>> +    BasicBlock *BB = PhiDef->getIncomingBlock(i);
>> +    BranchInst *BI = dyn_cast<BranchInst>(BB->getTerminator());
>> +    if (BI && BI->isConditional())
>> +      return BI;
>> +    BB = BB->getSinglePredecessor();
>> +    if (!BB)
>> +      return nullptr;
>> +    BI = dyn_cast<BranchInst>(BB->getTerminator());
>> +    if (!BI || BI->isUnconditional())
>> +      return nullptr;
>> +    return BI;
>> +  };
>> +
>> +  // Now walk through all Phi operands to find phi oprerands with values
>> +  // conflicting with the expected phi output value. Any such operand
>> +  // indicates the incoming edge to that operand is unlikely.
>> +  for (unsigned i = 0, e = PhiDef->getNumIncomingValues(); i != e; ++i)
>> {
>> +
>> +    Value *PhiOpnd = PhiDef->getIncomingValue(i);
>> +    ConstantInt *CI = dyn_cast<ConstantInt>(PhiOpnd);
>> +    if (!CI)
>> +      continue;
>> +
>> +    // Not an interesting case when IsUnlikely is false -- we can not
>> infer
>> +    // anything useful when the operand value matches the expected phi
>> +    // output.
>> +    if (ExpectedPhiValue == ApplyOperations(CI->getValue()))
>> +      continue;
>> +
>> +    BranchInst *BI = GetDomConditional(i);
>> +    if (!BI)
>> +      continue;
>> +
>> +    MDBuilder MDB(PhiDef->getContext());
>> +
>> +    // There are two situations in which an operand of the PhiDef comes
>> +    // from a given successor of a branch instruction BI.
>> +    // 1) When the incoming block of the operand is the successor block;
>> +    // 2) When the incoming block is BI's enclosing block and the
>> +    // successor is the PhiDef's enclosing block.
>> +    //
>> +    // Returns true if the operand which comes from OpndIncomingBB
>> +    // comes from outgoing edge of BI that leads to Succ block.
>> +    auto *OpndIncomingBB = PhiDef->getIncomingBlock(i);
>> +    auto IsOpndComingFromSuccessor = [&](BasicBlock *Succ) {
>> +      if (OpndIncomingBB == Succ)
>> +        // If this successor is the incoming block for this
>> +        // Phi operand, then this successor does lead to the Phi.
>> +        return true;
>> +      if (OpndIncomingBB == BI->getParent() && Succ ==
>> PhiDef->getParent())
>> +        // Otherwise, if the edge is directly from the branch
>> +        // to the Phi, this successor is the one feeding this
>> +        // Phi operand.
>> +        return true;
>> +      return false;
>> +    };
>> +
>> +    if (IsOpndComingFromSuccessor(BI->getSuccessor(1)))
>> +      BI->setMetadata(
>> +          LLVMContext::MD_prof,
>> +          MDB.createBranchWeights(LikelyBranchWeight,
>> UnlikelyBranchWeight));
>> +    else if (IsOpndComingFromSuccessor(BI->getSuccessor(0)))
>> +      BI->setMetadata(
>> +          LLVMContext::MD_prof,
>> +          MDB.createBranchWeights(UnlikelyBranchWeight,
>> LikelyBranchWeight));
>> +  }
>> +}
>> +
>>  // Handle both BranchInst and SelectInst.
>>  template <class BrSelInst> static bool handleBrSelExpect(BrSelInst &BSI)
>> {
>>
>> @@ -187,6 +331,10 @@ static bool lowerExpectIntrinsic(Functio
>>
>>        Function *Fn = CI->getCalledFunction();
>>        if (Fn && Fn->getIntrinsicID() == Intrinsic::expect) {
>> +        // Before erasing the llvm.expect, walk backward to find
>> +        // phi that define llvm.expect's first arg, and
>> +        // infer branch probability:
>> +        handlePhiDef(CI);
>>          Value *Exp = CI->getArgOperand(0);
>>          CI->replaceAllUsesWith(Exp);
>>          CI->eraseFromParent();
>>
>> Added: llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_merge.ll
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transfor
>> ms/LowerExpectIntrinsic/phi_merge.ll?rev=304517&view=auto
>> ============================================================
>> ==================
>> --- llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_merge.ll (added)
>> +++ llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_merge.ll Thu
>> Jun  1 21:09:31 2017
>> @@ -0,0 +1,356 @@
>> +; RUN: opt -lower-expect  -S -o - < %s | FileCheck %s
>> +; RUN: opt -S -passes='function(lower-expect)' < %s | FileCheck %s
>> +
>> +; The C case
>> +; if (__builtin_expect((x > goo() && y > hoo() && z > too()), 1))
>> +; For the above case, all 3 branches should be annotated.
>> +;
>> +; if (__builtin_expect((x > goo() && y > hoo() && z > too()), 0))
>> +; For the above case, we don't have enough information, so
>> +; only the last branch is annotated.
>> +
>> +define void @foo(i32 %arg, i32 %arg1, i32 %arg2, i32 %arg3) {
>> +; CHECK-LABEL: void @foo
>> +bb:
>> +  %tmp8 = call i32  @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK: !prof [[WEIGHT:![0-9]+]]
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32  @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13, {{.*}}!prof [[WEIGHT]]
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i32  @too()
>> +  %tmp17 = icmp sgt i32 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i1 [ false, %bb10 ], [ false, %bb ], [ %tmp17, %bb14 ]
>> +  %tmp20 = xor i1 %tmp19, true
>> +  %tmp21 = xor i1 %tmp20, true
>> +  %tmp22 = zext i1 %tmp21 to i32
>> +  %tmp23 = sext i32 %tmp22 to i64
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 1)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32  @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32  @hoo()
>> +  br label %bb30
>> +
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +define void @foo2(i32 %arg, i32 %arg1, i32 %arg2, i32 %arg3) {
>> +; CHECK-LABEL: void @foo2
>> +bb:
>> +  %tmp8 = call i32  @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK:  br i1 %tmp9
>> +; CHECK-NOT: !prof
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32  @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13
>> +; CHECK-NOT: !prof
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i32 @too()
>> +  %tmp17 = icmp sgt i32 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i1 [ false, %bb10 ], [ false, %bb ], [ %tmp17, %bb14 ]
>> +  %tmp20 = xor i1 %tmp19, true
>> +  %tmp21 = xor i1 %tmp20, true
>> +  %tmp22 = zext i1 %tmp21 to i32
>> +  %tmp23 = sext i32 %tmp22 to i64
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 0)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT2:![0-9]+]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32 @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32 @hoo()
>> +  br label %bb30
>> +
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +define void @foo_i32(i32 %arg, i32 %arg1, i32 %arg2, i32 %arg3) {
>> +; CHECK-LABEL: void @foo_i32
>> +bb:
>> +  %tmp8 = call i32  @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK: !prof [[WEIGHT]]
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32 @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13, {{.*}}!prof [[WEIGHT]]
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i32 @too()
>> +  %tmp17 = icmp sgt i32 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i32 [ 5, %bb10 ], [ 5, %bb ], [ %tmp16, %bb14 ]
>> +  %tmp23 = sext i32 %tmp19 to i64
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 4)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32 @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32 @hoo()
>> +  br label %bb30
>> +
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +
>> +define void @foo_i32_not_unlikely(i32 %arg, i32 %arg1, i32 %arg2, i32
>> %arg3)  {
>> +; CHECK-LABEL: void @foo_i32_not_unlikely
>> +bb:
>> +  %tmp8 = call i32 @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK: br i1 %tmp9
>> +; CHECK-NOT: !prof
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32 @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13
>> +; CHECK-NOT: !prof
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i32  @too()
>> +  %tmp17 = icmp sgt i32 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i32 [ 4, %bb10 ], [ 4, %bb ], [ %tmp16, %bb14 ]
>> +  %tmp23 = sext i32 %tmp19 to i64
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 4)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32  @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32 @hoo()
>> +  br label %bb30
>> +
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +define void @foo_i32_xor(i32 %arg, i32 %arg1, i32 %arg2, i32 %arg3)  {
>> +; CHECK-LABEL: void @foo_i32_xor
>> +bb:
>> +  %tmp8 = call i32  @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK: br i1 %tmp9,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32  @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i32  @too()
>> +  %tmp17 = icmp sgt i32 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i32 [ 6, %bb10 ], [ 6, %bb ], [ %tmp16, %bb14 ]
>> +  %tmp20 = xor i32 %tmp19, 3
>> +  %tmp23 = sext i32 %tmp20 to i64
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 4)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32 @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32 @hoo()
>> +  br label %bb30
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +define void @foo_i8_sext(i32 %arg, i32 %arg1, i8 %arg2, i32 %arg3)  {
>> +; CHECK-LABEL: void @foo_i8_sext
>> +bb:
>> +  %tmp8 = call i32  @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK: br i1 %tmp9,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32  @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i8  @too8()
>> +  %tmp17 = icmp sgt i8 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i8 [ 255, %bb10 ], [ 255, %bb ], [ %tmp16, %bb14 ]
>> +  %tmp23 = sext i8 %tmp19 to i64
>> +; after sign extension, the operand value becomes -1 which does not
>> match 255
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 255)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32 @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32 @hoo()
>> +  br label %bb30
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +define void @foo_i8_sext_not_unlikely(i32 %arg, i32 %arg1, i8 %arg2, i32
>> %arg3)  {
>> +; CHECK-LABEL: void @foo_i8_sext_not_unlikely
>> +bb:
>> +  %tmp8 = call i32  @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK: br i1 %tmp9
>> +; CHECK-NOT: !prof
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32  @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13
>> +; CHECK-NOT: !prof
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i8  @too8()
>> +  %tmp17 = icmp sgt i8 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i8 [ 255, %bb10 ], [ 255, %bb ], [ %tmp16, %bb14 ]
>> +  %tmp23 = sext i8 %tmp19 to i64
>> +; after sign extension, the operand value becomes -1 which matches -1
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 -1)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32 @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32 @hoo()
>> +  br label %bb30
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +
>> +define void @foo_i32_xor_not_unlikely(i32 %arg, i32 %arg1, i32 %arg2,
>> i32 %arg3)  {
>> +; CHECK-LABEL: void @foo_i32_xor_not_unlikely
>> +bb:
>> +  %tmp8 = call i32 @goo()
>> +  %tmp9 = icmp sgt i32 %tmp8, %arg
>> +  br i1 %tmp9, label %bb10, label %bb18
>> +; CHECK: br i1 %tmp9
>> +; CHECK-NOT: !prof
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32  @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br i1 %tmp13, label %bb14, label %bb18
>> +; CHECK: br i1 %tmp13
>> +; CHECK-NOT: !prof
>> +
>> +bb14:                                             ; preds = %bb10
>> +  %tmp16 = call i32 @too()
>> +  %tmp17 = icmp sgt i32 %arg2, %tmp16
>> +  br label %bb18
>> +
>> +bb18:                                             ; preds = %bb14,
>> %bb10, %bb
>> +  %tmp19 = phi i32 [ 6, %bb10 ], [ 6, %bb ], [ %tmp16, %bb14 ]
>> +  %tmp20 = xor i32 %tmp19, 2
>> +  %tmp23 = sext i32 %tmp20 to i64
>> +  %tmp24 = call i64 @llvm.expect.i64(i64 %tmp23, i64 4)
>> +  %tmp25 = icmp ne i64 %tmp24, 0
>> +  br i1 %tmp25, label %bb26, label %bb28
>> +; CHECK: br i1 %tmp25,{{.*}}!prof [[WEIGHT]]
>> +
>> +bb26:                                             ; preds = %bb18
>> +  %tmp27 = call i32 @goo()
>> +  br label %bb30
>> +
>> +bb28:                                             ; preds = %bb18
>> +  %tmp29 = call i32  @hoo()
>> +  br label %bb30
>> +
>> +bb30:                                             ; preds = %bb28, %bb26
>> +  ret void
>> +}
>> +
>> +declare i32 @goo()
>> +
>> +declare i32 @hoo()
>> +
>> +declare i32 @too()
>> +
>> +declare i8 @too8()
>> +
>> +; Function Attrs: nounwind readnone
>> +declare i64 @llvm.expect.i64(i64, i64)
>> +
>> +!llvm.ident = !{!0}
>> +
>> +!0 = !{!"clang version 5.0.0 (trunk 302965)"}
>> +; CHECK: [[WEIGHT]] = !{!"branch_weights", i32 2000, i32 1}
>> +; CHECK: [[WEIGHT2]] = !{!"branch_weights", i32 1, i32 2000}
>>
>> Added: llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_or.ll
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transfor
>> ms/LowerExpectIntrinsic/phi_or.ll?rev=304517&view=auto
>> ============================================================
>> ==================
>> --- llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_or.ll (added)
>> +++ llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_or.ll Thu Jun  1
>> 21:09:31 2017
>> @@ -0,0 +1,103 @@
>> +; RUN: opt -lower-expect  -S -o - < %s | FileCheck %s
>> +; RUN: opt -S -passes='function(lower-expect)' < %s | FileCheck %s
>> +;
>> +; if (__builtin_expect((x > goo() || y > hoo()), 1)) {
>> +;  ..
>> +; }
>> +; For the above case, only the second branch should be
>> +; annotated.
>> +; if (__builtin_expect((x > goo() || y > hoo()), 0)) {
>> +;  ..
>> +; }
>> +; For the above case, two branches should be annotated.
>> +; Function Attrs: noinline nounwind uwtable
>> +define void @foo(i32 %arg, i32 %arg1, i32 %arg2, i32 %arg3)  {
>> +; CHECK-LABEL: void @foo
>> +bb:
>> +  %tmp8 = call i32 @goo()
>> +  %tmp9 = icmp slt i32 %arg, %tmp8
>> +  br i1 %tmp9, label %bb14, label %bb10
>> +; CHECK: br i1 %tmp9
>> +; CHECK-NOT: br i1 %tmp9{{.*}}!prof
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp12 = call i32  @hoo()
>> +  %tmp13 = icmp sgt i32 %arg1, %tmp12
>> +  br label %bb14
>> +
>> +bb14:                                             ; preds = %bb10, %bb
>> +  %tmp15 = phi i1 [ true, %bb ], [ %tmp13, %bb10 ]
>> +  %tmp16 = zext i1 %tmp15 to i32
>> +  %tmp17 = sext i32 %tmp16 to i64
>> +  %expect = call i64 @llvm.expect.i64(i64 %tmp17, i64 1)
>> +  %tmp18 = icmp ne i64 %expect, 0
>> +  br i1 %tmp18, label %bb19, label %bb21
>> +; CHECK: br i1 %tmp18{{.*}}!prof [[WEIGHT:![0-9]+]]
>> +
>> +bb19:                                             ; preds = %bb14
>> +  %tmp20 = call i32 @goo()
>> +  br label %bb23
>> +
>> +bb21:                                             ; preds = %bb14
>> +  %tmp22 = call i32  @hoo()
>> +  br label %bb23
>> +
>> +bb23:                                             ; preds = %bb21, %bb19
>> +  ret void
>> +}
>> +
>> +define void @foo2(i32 %arg, i32 %arg1, i32 %arg2, i32 %arg3)  {
>> +; CHECK-LABEL: void @foo2
>> +bb:
>> +  %tmp = alloca i32, align 4
>> +  %tmp4 = alloca i32, align 4
>> +  %tmp5 = alloca i32, align 4
>> +  %tmp6 = alloca i32, align 4
>> +  store i32 %arg, i32* %tmp, align 4
>> +  store i32 %arg1, i32* %tmp4, align 4
>> +  store i32 %arg2, i32* %tmp5, align 4
>> +  store i32 %arg3, i32* %tmp6, align 4
>> +  %tmp7 = load i32, i32* %tmp, align 4
>> +  %tmp8 = call i32  @goo()
>> +  %tmp9 = icmp slt i32 %tmp7, %tmp8
>> +  br i1 %tmp9, label %bb14, label %bb10
>> +; CHECK: br i1 %tmp9{{.*}}!prof [[WEIGHT2:![0-9]+]]
>> +
>> +bb10:                                             ; preds = %bb
>> +  %tmp11 = load i32, i32* %tmp5, align 4
>> +  %tmp12 = call i32 @hoo()
>> +  %tmp13 = icmp sgt i32 %tmp11, %tmp12
>> +  br label %bb14
>> +
>> +bb14:                                             ; preds = %bb10, %bb
>> +  %tmp15 = phi i1 [ true, %bb ], [ %tmp13, %bb10 ]
>> +  %tmp16 = zext i1 %tmp15 to i32
>> +  %tmp17 = sext i32 %tmp16 to i64
>> +  %expect = call i64 @llvm.expect.i64(i64 %tmp17, i64 0)
>> +  %tmp18 = icmp ne i64 %expect, 0
>> +  br i1 %tmp18, label %bb19, label %bb21
>> +; CHECK: br i1 %tmp18{{.*}}!prof [[WEIGHT2]]
>> +
>> +bb19:                                             ; preds = %bb14
>> +  %tmp20 = call i32 @goo()
>> +  br label %bb23
>> +
>> +bb21:                                             ; preds = %bb14
>> +  %tmp22 = call i32 @hoo()
>> +  br label %bb23
>> +
>> +bb23:                                             ; preds = %bb21, %bb19
>> +  ret void
>> +}
>> +
>> +declare i32 @goo()
>> +declare i32 @hoo()
>> +declare i64 @llvm.expect.i64(i64, i64)
>> +
>> +
>> +!llvm.ident = !{!0}
>> +
>> +
>> +!0 = !{!"clang version 5.0.0 (trunk 302965)"}
>> +; CHECK: [[WEIGHT]] = !{!"branch_weights", i32 2000, i32 1}
>> +; CHECK: [[WEIGHT2]] = !{!"branch_weights", i32 1, i32 2000}
>>
>> Added: llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_tern.ll
>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transfor
>> ms/LowerExpectIntrinsic/phi_tern.ll?rev=304517&view=auto
>> ============================================================
>> ==================
>> --- llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_tern.ll (added)
>> +++ llvm/trunk/test/Transforms/LowerExpectIntrinsic/phi_tern.ll Thu Jun
>> 1 21:09:31 2017
>> @@ -0,0 +1,56 @@
>> +; RUN: opt -lower-expect  -S -o - < %s | FileCheck %s
>> +; RUN: opt -S -passes='function(lower-expect)' < %s | FileCheck %s
>> +
>> +; return __builtin_expect((a > b ? 1, goo(), 0);
>> +;
>> +; Function Attrs: noinline nounwind uwtable
>> +define i32 @foo(i32 %arg, i32 %arg1)  {
>> +; CHECK-LABEL: i32 @foo
>> +bb:
>> +  %tmp5 = icmp sgt i32 %arg, %arg1
>> +  br i1 %tmp5, label %bb9, label %bb7
>> +; CHECK: br i1 %tmp5{{.*}}!prof [[WEIGHT:![0-9]+]]
>> +
>> +bb7:                                              ; preds = %bb
>> +  %tmp8 = call i32 @goo()
>> +  br label %bb9
>> +
>> +bb9:                                              ; preds = %bb7, %bb9
>> +  %tmp10 = phi i32 [ 1, %bb ], [ %tmp8, %bb7 ]
>> +  %tmp11 = sext i32 %tmp10 to i64
>> +  %expect = call i64 @llvm.expect.i64(i64 %tmp11, i64 0)
>> +  %tmp12 = trunc i64 %expect to i32
>> +  ret i32 %tmp12
>> +}
>> +
>> +define i32 @foo2(i32 %arg, i32 %arg1)  {
>> +bb:
>> +  %tmp5 = icmp sgt i32 %arg, %arg1
>> +  br i1 %tmp5, label %bb6, label %bb7
>> +; CHECK: br i1 %tmp5{{.*}}!prof [[WEIGHT:![0-9]+]]
>> +
>> +bb6:                                              ; preds = %bb
>> +  br label %bb9
>> +
>> +bb7:                                              ; preds = %bb
>> +  %tmp8 = call i32 @goo()
>> +  br label %bb9
>> +
>> +bb9:                                              ; preds = %bb7, %bb6
>> +  %tmp10 = phi i32 [ 1, %bb6 ], [ %tmp8, %bb7 ]
>> +  %tmp11 = sext i32 %tmp10 to i64
>> +  %expect = call i64 @llvm.expect.i64(i64 %tmp11, i64 0)
>> +  %tmp12 = trunc i64 %expect to i32
>> +  ret i32 %tmp12
>> +}
>> +
>> +declare i32 @goo()
>> +declare i64 @llvm.expect.i64(i64, i64)
>> +
>> +
>> +
>> +!llvm.ident = !{!0}
>> +
>> +!0 = !{!"clang version 5.0.0 (trunk 302965)"}
>> +
>> +; CHECK: [[WEIGHT]] = !{!"branch_weights", i32 1, i32 2000}
>>
>>
>> _______________________________________________
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>> llvm-commits at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
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