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

Greg Bedwell via llvm-commits llvm-commits at lists.llvm.org
Wed Jun 7 10:12:33 PDT 2017


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/Transforms/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->
> getArgOperand(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/Transforms/
> 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/Transforms/
> 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/Transforms/
> 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
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