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-rw-r--r--lib/Transforms/InstCombine/InstCombine.h4
-rw-r--r--lib/Transforms/InstCombine/InstructionCombining.cpp353
-rw-r--r--test/Transforms/InstCombine/cast.ll197
3 files changed, 502 insertions, 52 deletions
diff --git a/lib/Transforms/InstCombine/InstCombine.h b/lib/Transforms/InstCombine/InstCombine.h
index 41017c5287..7467eca7ab 100644
--- a/lib/Transforms/InstCombine/InstCombine.h
+++ b/lib/Transforms/InstCombine/InstCombine.h
@@ -367,6 +367,10 @@ private:
Value *EvaluateInDifferentType(Value *V, Type *Ty, bool isSigned);
+
+ /// Descale - Return a value X such that Val = X * Scale, or null if none. If
+ /// the multiplication is known not to overflow then NoSignedWrap is set.
+ Value *Descale(Value *Val, APInt Scale, bool &NoSignedWrap);
};
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index 5356fdcba7..390b63c196 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -805,6 +805,244 @@ static bool shouldMergeGEPs(GEPOperator &GEP, GEPOperator &Src) {
return true;
}
+/// Descale - Return a value X such that Val = X * Scale, or null if none. If
+/// the multiplication is known not to overflow then NoSignedWrap is set.
+Value *InstCombiner::Descale(Value *Val, APInt Scale, bool &NoSignedWrap) {
+ assert(isa<IntegerType>(Val->getType()) && "Can only descale integers!");
+ assert(cast<IntegerType>(Val->getType())->getBitWidth() ==
+ Scale.getBitWidth() && "Scale not compatible with value!");
+
+ // If Val is zero or Scale is one then Val = Val * Scale.
+ if (match(Val, m_Zero()) || Scale == 1) {
+ NoSignedWrap = true;
+ return Val;
+ }
+
+ // If Scale is zero then it does not divide Val.
+ if (Scale.isMinValue())
+ return 0;
+
+ // Look through chains of multiplications, searching for a constant that is
+ // divisible by Scale. For example, descaling X*(Y*(Z*4)) by a factor of 4
+ // will find the constant factor 4 and produce X*(Y*Z). Descaling X*(Y*8) by
+ // a factor of 4 will produce X*(Y*2). The principle of operation is to bore
+ // down from Val:
+ //
+ // Val = M1 * X || Analysis starts here and works down
+ // M1 = M2 * Y || Doesn't descend into terms with more
+ // M2 = Z * 4 \/ than one use
+ //
+ // Then to modify a term at the bottom:
+ //
+ // Val = M1 * X
+ // M1 = Z * Y || Replaced M2 with Z
+ //
+ // Then to work back up correcting nsw flags.
+
+ // Op - the term we are currently analyzing. Starts at Val then drills down.
+ // Replaced with its descaled value before exiting from the drill down loop.
+ Value *Op = Val;
+
+ // Parent - initially null, but after drilling down notes where Op came from.
+ // In the example above, Parent is (Val, 0) when Op is M1, because M1 is the
+ // 0'th operand of Val.
+ std::pair<Instruction*, unsigned> Parent;
+
+ // RequireNoSignedWrap - Set if the transform requires a descaling at deeper
+ // levels that doesn't overflow.
+ bool RequireNoSignedWrap = false;
+
+ // logScale - log base 2 of the scale. Negative if not a power of 2.
+ int32_t logScale = Scale.exactLogBase2();
+
+ for (;; Op = Parent.first->getOperand(Parent.second)) { // Drill down
+
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(Op)) {
+ // If Op is a constant divisible by Scale then descale to the quotient.
+ APInt Quotient(Scale), Remainder(Scale); // Init ensures right bitwidth.
+ APInt::sdivrem(CI->getValue(), Scale, Quotient, Remainder);
+ if (!Remainder.isMinValue())
+ // Not divisible by Scale.
+ return 0;
+ // Replace with the quotient in the parent.
+ Op = ConstantInt::get(CI->getType(), Quotient);
+ NoSignedWrap = true;
+ break;
+ }
+
+ if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Op)) {
+
+ if (BO->getOpcode() == Instruction::Mul) {
+ // Multiplication.
+ NoSignedWrap = BO->hasNoSignedWrap();
+ if (RequireNoSignedWrap && !NoSignedWrap)
+ return 0;
+
+ // There are three cases for multiplication: multiplication by exactly
+ // the scale, multiplication by a constant different to the scale, and
+ // multiplication by something else.
+ Value *LHS = BO->getOperand(0);
+ Value *RHS = BO->getOperand(1);
+
+ if (ConstantInt *CI = dyn_cast<ConstantInt>(RHS)) {
+ // Multiplication by a constant.
+ if (CI->getValue() == Scale) {
+ // Multiplication by exactly the scale, replace the multiplication
+ // by its left-hand side in the parent.
+ Op = LHS;
+ break;
+ }
+
+ // Otherwise drill down into the constant.
+ if (!Op->hasOneUse())
+ return 0;
+
+ Parent = std::make_pair(BO, 1);
+ continue;
+ }
+
+ // Multiplication by something else. Drill down into the left-hand side
+ // since that's where the reassociate pass puts the good stuff.
+ if (!Op->hasOneUse())
+ return 0;
+
+ Parent = std::make_pair(BO, 0);
+ continue;
+ }
+
+ if (logScale > 0 && BO->getOpcode() == Instruction::Shl &&
+ isa<ConstantInt>(BO->getOperand(1))) {
+ // Multiplication by a power of 2.
+ NoSignedWrap = BO->hasNoSignedWrap();
+ if (RequireNoSignedWrap && !NoSignedWrap)
+ return 0;
+
+ Value *LHS = BO->getOperand(0);
+ int32_t Amt = cast<ConstantInt>(BO->getOperand(1))->
+ getLimitedValue(Scale.getBitWidth());
+ // Op = LHS << Amt.
+
+ if (Amt == logScale) {
+ // Multiplication by exactly the scale, replace the multiplication
+ // by its left-hand side in the parent.
+ Op = LHS;
+ break;
+ }
+ if (Amt < logScale || !Op->hasOneUse())
+ return 0;
+
+ // Multiplication by more than the scale. Reduce the multiplying amount
+ // by the scale in the parent.
+ Parent = std::make_pair(BO, 1);
+ Op = ConstantInt::get(BO->getType(), Amt - logScale);
+ break;
+ }
+ }
+
+ if (!Op->hasOneUse())
+ return 0;
+
+ if (CastInst *Cast = dyn_cast<CastInst>(Op)) {
+ if (Cast->getOpcode() == Instruction::SExt) {
+ // Op is sign-extended from a smaller type, descale in the smaller type.
+ unsigned SmallSize = Cast->getSrcTy()->getPrimitiveSizeInBits();
+ APInt SmallScale = Scale.trunc(SmallSize);
+ // Suppose Op = sext X, and we descale X as Y * SmallScale. We want to
+ // descale Op as (sext Y) * Scale. In order to have
+ // sext (Y * SmallScale) = (sext Y) * Scale
+ // some conditions need to hold however: SmallScale must sign-extend to
+ // Scale and the multiplication Y * SmallScale should not overflow.
+ if (SmallScale.sext(Scale.getBitWidth()) != Scale)
+ // SmallScale does not sign-extend to Scale.
+ return 0;
+ assert(SmallScale.exactLogBase2() == logScale);
+ // Require that Y * SmallScale must not overflow.
+ RequireNoSignedWrap = true;
+
+ // Drill down through the cast.
+ Parent = std::make_pair(Cast, 0);
+ Scale = SmallScale;
+ continue;
+ }
+
+ if (Cast->getOperand(0)) {
+ // Op is truncated from a larger type, descale in the larger type.
+ // Suppose Op = trunc X, and we descale X as Y * sext Scale. Then
+ // trunc (Y * sext Scale) = (trunc Y) * Scale
+ // always holds. However (trunc Y) * Scale may overflow even if
+ // trunc (Y * sext Scale) does not, so nsw flags need to be cleared
+ // from this point up in the expression (see later).
+ if (RequireNoSignedWrap)
+ return 0;
+
+ // Drill down through the cast.
+ unsigned LargeSize = Cast->getSrcTy()->getPrimitiveSizeInBits();
+ Parent = std::make_pair(Cast, 0);
+ Scale = Scale.sext(LargeSize);
+ if (logScale + 1 == (int32_t)Cast->getType()->getPrimitiveSizeInBits())
+ logScale = -1;
+ assert(Scale.exactLogBase2() == logScale);
+ continue;
+ }
+ }
+
+ // Unsupported expression, bail out.
+ return 0;
+ }
+
+ // We know that we can successfully descale, so from here on we can safely
+ // modify the IR. Op holds the descaled version of the deepest term in the
+ // expression. NoSignedWrap is 'true' if multiplying Op by Scale is known
+ // not to overflow.
+
+ if (!Parent.first)
+ // The expression only had one term.
+ return Op;
+
+ // Rewrite the parent using the descaled version of its operand.
+ assert(Parent.first->hasOneUse() && "Drilled down when more than one use!");
+ assert(Op != Parent.first->getOperand(Parent.second) &&
+ "Descaling was a no-op?");
+ Parent.first->setOperand(Parent.second, Op);
+ Worklist.Add(Parent.first);
+
+ // Now work back up the expression correcting nsw flags. The logic is based
+ // on the following observation: if X * Y is known not to overflow as a signed
+ // multiplication, and Y is replaced by a value Z with smaller absolute value,
+ // then X * Z will not overflow as a signed multiplication either. As we work
+ // our way up, having NoSignedWrap 'true' means that the descaled value at the
+ // current level has strictly smaller absolute value than the original.
+ Instruction *Ancestor = Parent.first;
+ do {
+ if (BinaryOperator *BO = dyn_cast<BinaryOperator>(Ancestor)) {
+ // If the multiplication wasn't nsw then we can't say anything about the
+ // value of the descaled multiplication, and we have to clear nsw flags
+ // from this point on up.
+ bool OpNoSignedWrap = BO->hasNoSignedWrap();
+ NoSignedWrap &= OpNoSignedWrap;
+ if (NoSignedWrap != OpNoSignedWrap) {
+ BO->setHasNoSignedWrap(NoSignedWrap);
+ Worklist.Add(Ancestor);
+ }
+ } else if (Ancestor->getOpcode() == Instruction::Trunc) {
+ // The fact that the descaled input to the trunc has smaller absolute
+ // value than the original input doesn't tell us anything useful about
+ // the absolute values of the truncations.
+ NoSignedWrap = false;
+ }
+ assert((Ancestor->getOpcode() != Instruction::SExt || NoSignedWrap) &&
+ "Failed to keep proper track of nsw flags while drilling down?");
+
+ if (Ancestor == Val)
+ // Got to the top, all done!
+ return Val;
+
+ // Move up one level in the expression.
+ assert(Ancestor->hasOneUse() && "Drilled down when more than one use!");
+ Ancestor = Ancestor->use_back();
+ } while (1);
+}
+
Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
SmallVector<Value*, 8> Ops(GEP.op_begin(), GEP.op_end());
@@ -855,7 +1093,7 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
if (!shouldMergeGEPs(*cast<GEPOperator>(&GEP), *Src))
return 0;
- // Note that if our source is a gep chain itself that we wait for that
+ // Note that if our source is a gep chain itself then we wait for that
// chain to be resolved before we perform this transformation. This
// avoids us creating a TON of code in some cases.
if (GEPOperator *SrcGEP =
@@ -987,63 +1225,74 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
}
// Transform things like:
+ // %V = mul i64 %N, 4
+ // %t = getelementptr i8* bitcast (i32* %arr to i8*), i32 %V
+ // into: %t1 = getelementptr i32* %arr, i32 %N; bitcast
+ if (TD && ResElTy->isSized() && SrcElTy->isSized()) {
+ // Check that changing the type amounts to dividing the index by a scale
+ // factor.
+ uint64_t ResSize = TD->getTypeAllocSize(ResElTy);
+ uint64_t SrcSize = TD->getTypeAllocSize(SrcElTy);
+ if (ResSize && SrcSize % ResSize == 0) {
+ Value *Idx = GEP.getOperand(1);
+ unsigned BitWidth = Idx->getType()->getPrimitiveSizeInBits();
+ uint64_t Scale = SrcSize / ResSize;
+
+ // Earlier transforms ensure that the index has type IntPtrType, which
+ // considerably simplifies the logic by eliminating implicit casts.
+ assert(Idx->getType() == TD->getIntPtrType(GEP.getContext()) &&
+ "Index not cast to pointer width?");
+
+ bool NSW;
+ if (Value *NewIdx = Descale(Idx, APInt(BitWidth, Scale), NSW)) {
+ // Successfully decomposed Idx as NewIdx * Scale, form a new GEP.
+ // If the multiplication NewIdx * Scale may overflow then the new
+ // GEP may not be "inbounds".
+ Value *NewGEP = GEP.isInBounds() && NSW ?
+ Builder->CreateInBoundsGEP(StrippedPtr, NewIdx, GEP.getName()) :
+ Builder->CreateGEP(StrippedPtr, NewIdx, GEP.getName());
+ // The NewGEP must be pointer typed, so must the old one -> BitCast
+ return new BitCastInst(NewGEP, GEP.getType());
+ }
+ }
+ }
+
+ // Similarly, transform things like:
// getelementptr i8* bitcast ([100 x double]* X to i8*), i32 %tmp
// (where tmp = 8*tmp2) into:
// getelementptr [100 x double]* %arr, i32 0, i32 %tmp2; bitcast
-
- if (TD && SrcElTy->isArrayTy() && ResElTy->isIntegerTy(8)) {
+ if (TD && ResElTy->isSized() && SrcElTy->isSized() &&
+ SrcElTy->isArrayTy()) {
+ // Check that changing to the array element type amounts to dividing the
+ // index by a scale factor.
+ uint64_t ResSize = TD->getTypeAllocSize(ResElTy);
uint64_t ArrayEltSize =
- TD->getTypeAllocSize(cast<ArrayType>(SrcElTy)->getElementType());
-
- // Check to see if "tmp" is a scale by a multiple of ArrayEltSize. We
- // allow either a mul, shift, or constant here.
- Value *NewIdx = 0;
- ConstantInt *Scale = 0;
- if (ArrayEltSize == 1) {
- NewIdx = GEP.getOperand(1);
- Scale = ConstantInt::get(cast<IntegerType>(NewIdx->getType()), 1);
- } else if (ConstantInt *CI = dyn_cast<ConstantInt>(GEP.getOperand(1))) {
- NewIdx = ConstantInt::get(CI->getType(), 1);
- Scale = CI;
- } else if (Instruction *Inst =dyn_cast<Instruction>(GEP.getOperand(1))){
- if (Inst->getOpcode() == Instruction::Shl &&
- isa<ConstantInt>(Inst->getOperand(1))) {
- ConstantInt *ShAmt = cast<ConstantInt>(Inst->getOperand(1));
- uint32_t ShAmtVal = ShAmt->getLimitedValue(64);
- Scale = ConstantInt::get(cast<IntegerType>(Inst->getType()),
- 1ULL << ShAmtVal);
- NewIdx = Inst->getOperand(0);
- } else if (Inst->getOpcode() == Instruction::Mul &&
- isa<ConstantInt>(Inst->getOperand(1))) {
- Scale = cast<ConstantInt>(Inst->getOperand(1));
- NewIdx = Inst->getOperand(0);
+ TD->getTypeAllocSize(cast<ArrayType>(SrcElTy)->getElementType());
+ if (ResSize && ArrayEltSize % ResSize == 0) {
+ Value *Idx = GEP.getOperand(1);
+ unsigned BitWidth = Idx->getType()->getPrimitiveSizeInBits();
+ uint64_t Scale = ArrayEltSize / ResSize;
+
+ // Earlier transforms ensure that the index has type IntPtrType, which
+ // considerably simplifies the logic by eliminating implicit casts.
+ assert(Idx->getType() == TD->getIntPtrType(GEP.getContext()) &&
+ "Index not cast to pointer width?");
+
+ bool NSW;
+ if (Value *NewIdx = Descale(Idx, APInt(BitWidth, Scale), NSW)) {
+ // Successfully decomposed Idx as NewIdx * Scale, form a new GEP.
+ // If the multiplication NewIdx * Scale may overflow then the new
+ // GEP may not be "inbounds".
+ Value *Off[2];
+ Off[0] = Constant::getNullValue(Type::getInt32Ty(GEP.getContext()));
+ Off[1] = NewIdx;
+ Value *NewGEP = GEP.isInBounds() && NSW ?
+ Builder->CreateInBoundsGEP(StrippedPtr, Off, GEP.getName()) :
+ Builder->CreateGEP(StrippedPtr, Off, GEP.getName());
+ // The NewGEP must be pointer typed, so must the old one -> BitCast
+ return new BitCastInst(NewGEP, GEP.getType());
}
}
-
- // If the index will be to exactly the right offset with the scale taken
- // out, perform the transformation. Note, we don't know whether Scale is
- // signed or not. We'll use unsigned version of division/modulo
- // operation after making sure Scale doesn't have the sign bit set.
- if (ArrayEltSize && Scale && Scale->getSExtValue() >= 0LL &&
- Scale->getZExtValue() % ArrayEltSize == 0) {
- Scale = ConstantInt::get(Scale->getType(),
- Scale->getZExtValue() / ArrayEltSize);
- if (Scale->getZExtValue() != 1) {
- Constant *C = ConstantExpr::getIntegerCast(Scale, NewIdx->getType(),
- false /*ZExt*/);
- NewIdx = Builder->CreateMul(NewIdx, C, "idxscale");
- }
-
- // Insert the new GEP instruction.
- Value *Idx[2];
- Idx[0] = Constant::getNullValue(Type::getInt32Ty(GEP.getContext()));
- Idx[1] = NewIdx;
- Value *NewGEP = GEP.isInBounds() ?
- Builder->CreateInBoundsGEP(StrippedPtr, Idx, GEP.getName()):
- Builder->CreateGEP(StrippedPtr, Idx, GEP.getName());
- // The NewGEP must be pointer typed, so must the old one -> BitCast
- return new BitCastInst(NewGEP, GEP.getType());
- }
}
}
}
diff --git a/test/Transforms/InstCombine/cast.ll b/test/Transforms/InstCombine/cast.ll
index 56e5ca3ff7..899ffddd5b 100644
--- a/test/Transforms/InstCombine/cast.ll
+++ b/test/Transforms/InstCombine/cast.ll
@@ -694,3 +694,200 @@ define i1 @test67(i1 %a, i32 %b) {
; CHECK: @test67
; CHECK: ret i1 false
}
+
+%s = type { i32, i32, i32 }
+
+define %s @test68(%s *%p, i64 %i) {
+; CHECK: @test68
+ %o = mul i64 %i, 12
+ %q = bitcast %s* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %o
+; CHECK-NEXT: getelementptr %s*
+ %r = bitcast i8* %pp to %s*
+ %l = load %s* %r
+; CHECK-NEXT: load %s*
+ ret %s %l
+; CHECK-NEXT: ret %s
+}
+
+define double @test69(double *%p, i64 %i) {
+; CHECK: @test69
+ %o = shl nsw i64 %i, 3
+ %q = bitcast double* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %o
+; CHECK-NEXT: getelementptr inbounds double*
+ %r = bitcast i8* %pp to double*
+ %l = load double* %r
+; CHECK-NEXT: load double*
+ ret double %l
+; CHECK-NEXT: ret double
+}
+
+define %s @test70(%s *%p, i64 %i) {
+; CHECK: @test70
+ %o = mul nsw i64 %i, 36
+; CHECK-NEXT: mul nsw i64 %i, 3
+ %q = bitcast %s* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %o
+; CHECK-NEXT: getelementptr inbounds %s*
+ %r = bitcast i8* %pp to %s*
+ %l = load %s* %r
+; CHECK-NEXT: load %s*
+ ret %s %l
+; CHECK-NEXT: ret %s
+}
+
+define double @test71(double *%p, i64 %i) {
+; CHECK: @test71
+ %o = shl i64 %i, 5
+; CHECK-NEXT: shl i64 %i, 2
+ %q = bitcast double* %p to i8*
+ %pp = getelementptr i8* %q, i64 %o
+; CHECK-NEXT: getelementptr double*
+ %r = bitcast i8* %pp to double*
+ %l = load double* %r
+; CHECK-NEXT: load double*
+ ret double %l
+; CHECK-NEXT: ret double
+}
+
+define double @test72(double *%p, i32 %i) {
+; CHECK: @test72
+ %so = mul nsw i32 %i, 8
+ %o = sext i32 %so to i64
+; CHECK-NEXT: sext i32 %i to i64
+ %q = bitcast double* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %o
+; CHECK-NEXT: getelementptr inbounds double*
+ %r = bitcast i8* %pp to double*
+ %l = load double* %r
+; CHECK-NEXT: load double*
+ ret double %l
+; CHECK-NEXT: ret double
+}
+
+define double @test73(double *%p, i128 %i) {
+; CHECK: @test73
+ %lo = mul nsw i128 %i, 8
+ %o = trunc i128 %lo to i64
+; CHECK-NEXT: trunc i128 %i to i64
+ %q = bitcast double* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %o
+; CHECK-NEXT: getelementptr double*
+ %r = bitcast i8* %pp to double*
+ %l = load double* %r
+; CHECK-NEXT: load double*
+ ret double %l
+; CHECK-NEXT: ret double
+}
+
+define double @test74(double *%p, i64 %i) {
+; CHECK: @test74
+ %q = bitcast double* %p to i64*
+ %pp = getelementptr inbounds i64* %q, i64 %i
+; CHECK-NEXT: getelementptr inbounds double*
+ %r = bitcast i64* %pp to double*
+ %l = load double* %r
+; CHECK-NEXT: load double*
+ ret double %l
+; CHECK-NEXT: ret double
+}
+
+define i32* @test75(i32* %p, i32 %x) {
+; CHECK: @test75
+ %y = shl i32 %x, 3
+; CHECK-NEXT: shl i32 %x, 3
+ %z = sext i32 %y to i64
+; CHECK-NEXT: sext i32 %y to i64
+ %q = bitcast i32* %p to i8*
+ %r = getelementptr i8* %q, i64 %z
+ %s = bitcast i8* %r to i32*
+ ret i32* %s
+}
+
+define %s @test76(%s *%p, i64 %i, i64 %j) {
+; CHECK: @test76
+ %o = mul i64 %i, 12
+ %o2 = mul nsw i64 %o, %j
+; CHECK-NEXT: %o2 = mul i64 %i, %j
+ %q = bitcast %s* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %o2
+; CHECK-NEXT: getelementptr %s* %p, i64 %o2
+ %r = bitcast i8* %pp to %s*
+ %l = load %s* %r
+; CHECK-NEXT: load %s*
+ ret %s %l
+; CHECK-NEXT: ret %s
+}
+
+define %s @test77(%s *%p, i64 %i, i64 %j) {
+; CHECK: @test77
+ %o = mul nsw i64 %i, 36
+ %o2 = mul nsw i64 %o, %j
+; CHECK-NEXT: %o = mul nsw i64 %i, 3
+; CHECK-NEXT: %o2 = mul nsw i64 %o, %j
+ %q = bitcast %s* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %o2
+; CHECK-NEXT: getelementptr inbounds %s* %p, i64 %o2
+ %r = bitcast i8* %pp to %s*
+ %l = load %s* %r
+; CHECK-NEXT: load %s*
+ ret %s %l
+; CHECK-NEXT: ret %s
+}
+
+define %s @test78(%s *%p, i64 %i, i64 %j, i32 %k, i32 %l, i128 %m, i128 %n) {
+; CHECK: @test78
+ %a = mul nsw i32 %k, 36
+; CHECK-NEXT: mul nsw i32 %k, 3
+ %b = mul nsw i32 %a, %l
+; CHECK-NEXT: mul nsw i32 %a, %l
+ %c = sext i32 %b to i128
+; CHECK-NEXT: sext i32 %b to i128
+ %d = mul nsw i128 %c, %m
+; CHECK-NEXT: mul nsw i128 %c, %m
+ %e = mul i128 %d, %n
+; CHECK-NEXT: mul i128 %d, %n
+ %f = trunc i128 %e to i64
+; CHECK-NEXT: trunc i128 %e to i64
+ %g = mul nsw i64 %f, %i
+; CHECK-NEXT: mul i64 %f, %i
+ %h = mul nsw i64 %g, %j
+; CHECK-NEXT: mul i64 %g, %j
+ %q = bitcast %s* %p to i8*
+ %pp = getelementptr inbounds i8* %q, i64 %h
+; CHECK-NEXT: getelementptr %s* %p, i64 %h
+ %r = bitcast i8* %pp to %s*
+ %load = load %s* %r
+; CHECK-NEXT: load %s*
+ ret %s %load
+; CHECK-NEXT: ret %s
+}
+
+define %s @test79(%s *%p, i64 %i, i32 %j) {
+; CHECK: @test79
+ %a = mul nsw i64 %i, 36
+; CHECK: mul nsw i64 %i, 36
+ %b = trunc i64 %a to i32
+ %c = mul i32 %b, %j
+ %q = bitcast %s* %p to i8*
+; CHECK: bitcast
+ %pp = getelementptr inbounds i8* %q, i32 %c
+ %r = bitcast i8* %pp to %s*
+ %l = load %s* %r
+ ret %s %l
+}
+
+define double @test80([100 x double]* %p, i32 %i) {
+; CHECK: @test80
+ %tmp = mul nsw i32 %i, 8
+; CHECK-NEXT: sext i32 %i to i64
+ %q = bitcast [100 x double]* %p to i8*
+ %pp = getelementptr i8* %q, i32 %tmp
+; CHECK-NEXT: getelementptr [100 x double]*
+ %r = bitcast i8* %pp to double*
+ %l = load double* %r
+; CHECK-NEXT: load double*
+ ret double %l
+; CHECK-NEXT: ret double
+}