From ae32815f9281a5a8d48014e180901fcdb658285a Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Sun, 7 Aug 2016 07:58:00 +0000
Subject: [rust-lang/llvm#47 1/4] [InstCombine] Infer inbounds on geps of
allocas
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277950 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Transforms/InstCombine/InstructionCombining.cpp | 19 +++++++++++++++++++
test/Transforms/InstCombine/getelementptr.ll | 6 +++---
2 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/lib/Transforms/InstCombine/InstructionCombining.cpp b/lib/Transforms/InstCombine/InstructionCombining.cpp
index 377ccb9c37f7..31b5ad6ae8af 100644
--- a/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -1898,6 +1898,25 @@ Instruction *InstCombiner::visitGetElementPtrInst(GetElementPtrInst &GEP) {
}
}
+ if (!GEP.isInBounds()) {
+ unsigned PtrWidth =
+ DL.getPointerSizeInBits(PtrOp->getType()->getPointerAddressSpace());
+ APInt BasePtrOffset(PtrWidth, 0);
+ Value *UnderlyingPtrOp =
+ PtrOp->stripAndAccumulateInBoundsConstantOffsets(DL,
+ BasePtrOffset);
+ if (auto *AI = dyn_cast<AllocaInst>(UnderlyingPtrOp)) {
+ if (GEP.accumulateConstantOffset(DL, BasePtrOffset) &&
+ BasePtrOffset.isNonNegative()) {
+ APInt AllocSize(PtrWidth, DL.getTypeAllocSize(AI->getAllocatedType()));
+ if (BasePtrOffset.ule(AllocSize)) {
+ return GetElementPtrInst::CreateInBounds(
+ PtrOp, makeArrayRef(Ops).slice(1), GEP.getName());
+ }
+ }
+ }
+ }
+
return nullptr;
}
diff --git a/test/Transforms/InstCombine/getelementptr.ll b/test/Transforms/InstCombine/getelementptr.ll
index 7446734e210c..14abd84fd18e 100644
--- a/test/Transforms/InstCombine/getelementptr.ll
+++ b/test/Transforms/InstCombine/getelementptr.ll
@@ -366,7 +366,7 @@ define i32 @test21() {
%rval = load i32, i32* %pbobel
ret i32 %rval
; CHECK-LABEL: @test21(
-; CHECK: getelementptr %intstruct, %intstruct* %pbob1, i64 0, i32 0
+; CHECK: getelementptr inbounds %intstruct, %intstruct* %pbob1, i64 0, i32 0
}
@@ -540,8 +540,8 @@ define i8* @test32(i8* %v) {
%G = load i8*, i8** %F
ret i8* %G
; CHECK-LABEL: @test32(
-; CHECK: %D = getelementptr [4 x i8*], [4 x i8*]* %A, i64 0, i64 1
-; CHECK: %F = getelementptr [4 x i8*], [4 x i8*]* %A, i64 0, i64 2
+; CHECK: %D = getelementptr inbounds [4 x i8*], [4 x i8*]* %A, i64 0, i64 1
+; CHECK: %F = getelementptr inbounds [4 x i8*], [4 x i8*]* %A, i64 0, i64 2
}
; PR3290
--
2.7.4
From d31c987130ff1bf9cea9a287195ecceda91c37d1 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Sun, 7 Aug 2016 07:58:10 +0000
Subject: [rust-lang/llvm#47 2/4] [InstSimplify] Try hard to simplify pointer
comparisons
Simplify ptrtoint comparisons involving operands with different source
types.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277951 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Analysis/InstructionSimplify.cpp | 10 ++++++++++
test/Transforms/InstSimplify/compare.ll | 13 +++++++++++++
2 files changed, 23 insertions(+)
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 7c6edbfca270..8b70d89d62cb 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -3092,6 +3092,16 @@ static Value *SimplifyICmpInst(unsigned Predicate, Value *LHS, Value *RHS,
if (LHS->getType()->isPointerTy())
if (auto *C = computePointerICmp(Q.DL, Q.TLI, Q.DT, Pred, Q.CxtI, LHS, RHS))
return C;
+ if (auto *CLHS = dyn_cast<PtrToIntOperator>(LHS))
+ if (auto *CRHS = dyn_cast<PtrToIntOperator>(RHS))
+ if (Q.DL.getTypeSizeInBits(CLHS->getPointerOperandType()) ==
+ Q.DL.getTypeSizeInBits(CLHS->getType()) &&
+ Q.DL.getTypeSizeInBits(CRHS->getPointerOperandType()) ==
+ Q.DL.getTypeSizeInBits(CRHS->getType()))
+ if (auto *C = computePointerICmp(Q.DL, Q.TLI, Q.DT, Pred, Q.CxtI,
+ CLHS->getPointerOperand(),
+ CRHS->getPointerOperand()))
+ return C;
if (GetElementPtrInst *GLHS = dyn_cast<GetElementPtrInst>(LHS)) {
if (GEPOperator *GRHS = dyn_cast<GEPOperator>(RHS)) {
diff --git a/test/Transforms/InstSimplify/compare.ll b/test/Transforms/InstSimplify/compare.ll
index 9d6fd74ae56f..3e7316ec6b48 100644
--- a/test/Transforms/InstSimplify/compare.ll
+++ b/test/Transforms/InstSimplify/compare.ll
@@ -205,6 +205,19 @@ define i1 @gep16(i8* %ptr, i32 %a) {
; CHECK-NEXT: ret i1 false
}
+define i1 @gep17() {
+; CHECK-LABEL: @gep17(
+ %alloca = alloca i32, align 4
+ %bc = bitcast i32* %alloca to [4 x i8]*
+ %gep1 = getelementptr inbounds i32, i32* %alloca, i32 1
+ %pti1 = ptrtoint i32* %gep1 to i32
+ %gep2 = getelementptr inbounds [4 x i8], [4 x i8]* %bc, i32 0, i32 1
+ %pti2 = ptrtoint i8* %gep2 to i32
+ %cmp = icmp ugt i32 %pti1, %pti2
+ ret i1 %cmp
+; CHECK-NEXT: ret i1 true
+}
+
define i1 @zext(i32 %x) {
; CHECK-LABEL: @zext(
%e1 = zext i32 %x to i64
--
2.7.4
From bd3e05cb1f5293635edff14fcf23cfc73985c977 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Sun, 7 Aug 2016 07:58:12 +0000
Subject: [rust-lang/llvm#47 3/4] [InstSimplify] Fold gep (gep V, C), (sub 0,
V) to C
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@277952 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Analysis/InstructionSimplify.cpp | 20 ++++++++++++++++++++
test/Transforms/InstSimplify/compare.ll | 13 +++++++++++++
2 files changed, 33 insertions(+)
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 8b70d89d62cb..9d2a47957125 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -3597,6 +3597,26 @@ static Value *SimplifyGEPInst(Type *SrcTy, ArrayRef<Value *> Ops,
}
}
+ // gep (gep V, C), (sub 0, V) -> C
+ if (Q.DL.getTypeAllocSize(LastType) == 1 &&
+ all_of(Ops.slice(1).drop_back(1),
+ [](Value *Idx) { return match(Idx, m_Zero()); })) {
+ unsigned PtrWidth =
+ Q.DL.getPointerSizeInBits(Ops[0]->getType()->getPointerAddressSpace());
+ if (Q.DL.getTypeSizeInBits(Ops.back()->getType()) == PtrWidth) {
+ APInt BasePtrOffset(PtrWidth, 0);
+ Value *StrippedBasePtr =
+ Ops[0]->stripAndAccumulateInBoundsConstantOffsets(Q.DL,
+ BasePtrOffset);
+
+ if (match(Ops.back(),
+ m_Sub(m_Zero(), m_PtrToInt(m_Specific(StrippedBasePtr))))) {
+ auto *CI = ConstantInt::get(GEPTy->getContext(), BasePtrOffset);
+ return ConstantExpr::getIntToPtr(CI, GEPTy);
+ }
+ }
+ }
+
// Check to see if this is constant foldable.
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
if (!isa<Constant>(Ops[i]))
diff --git a/test/Transforms/InstSimplify/compare.ll b/test/Transforms/InstSimplify/compare.ll
index 3e7316ec6b48..addb63c57222 100644
--- a/test/Transforms/InstSimplify/compare.ll
+++ b/test/Transforms/InstSimplify/compare.ll
@@ -218,6 +218,19 @@ define i1 @gep17() {
; CHECK-NEXT: ret i1 true
}
+define i32 @gep18() {
+; CHECK-LABEL: @gep18(
+ %alloca = alloca i32, align 4 ; alloca + 0
+ %gep = getelementptr inbounds i32, i32* %alloca, i32 1 ; alloca + 4
+ %bc = bitcast i32* %gep to [4 x i8]* ; alloca + 4
+ %pti = ptrtoint i32* %alloca to i32 ; alloca
+ %sub = sub i32 0, %pti ; -alloca
+ %add = getelementptr [4 x i8], [4 x i8]* %bc, i32 0, i32 %sub ; alloca + 4 - alloca == 4
+ %add_to_int = ptrtoint i8* %add to i32 ; 4
+ ret i32 %add_to_int ; 4
+; CHECK-NEXT: ret i32 4
+}
+
define i1 @zext(i32 %x) {
; CHECK-LABEL: @zext(
%e1 = zext i32 %x to i64
--
2.7.4
From c3eb3c7608f439231d0c1340af6b720f113b4bf4 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Tue, 16 Aug 2016 06:13:46 +0000
Subject: [rust-lang/llvm#47 4/4] [InstSimplify] Fold gep (gep V, C), (xor V,
-1) to C-1
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278779 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/Analysis/InstructionSimplify.cpp | 8 +++++++-
test/Transforms/InstSimplify/compare.ll | 13 -------------
2 files changed, 7 insertions(+), 14 deletions(-)
diff --git a/lib/Analysis/InstructionSimplify.cpp b/lib/Analysis/InstructionSimplify.cpp
index 9d2a47957125..f7a435d1ad46 100644
--- a/lib/Analysis/InstructionSimplify.cpp
+++ b/lib/Analysis/InstructionSimplify.cpp
@@ -3597,7 +3597,6 @@ static Value *SimplifyGEPInst(Type *SrcTy, ArrayRef<Value *> Ops,
}
}
- // gep (gep V, C), (sub 0, V) -> C
if (Q.DL.getTypeAllocSize(LastType) == 1 &&
all_of(Ops.slice(1).drop_back(1),
[](Value *Idx) { return match(Idx, m_Zero()); })) {
@@ -3609,11 +3608,18 @@ static Value *SimplifyGEPInst(Type *SrcTy, ArrayRef<Value *> Ops,
Ops[0]->stripAndAccumulateInBoundsConstantOffsets(Q.DL,
BasePtrOffset);
+ // gep (gep V, C), (sub 0, V) -> C
if (match(Ops.back(),
m_Sub(m_Zero(), m_PtrToInt(m_Specific(StrippedBasePtr))))) {
auto *CI = ConstantInt::get(GEPTy->getContext(), BasePtrOffset);
return ConstantExpr::getIntToPtr(CI, GEPTy);
}
+ // gep (gep V, C), (xor V, -1) -> C-1
+ if (match(Ops.back(),
+ m_Xor(m_PtrToInt(m_Specific(StrippedBasePtr)), m_AllOnes()))) {
+ auto *CI = ConstantInt::get(GEPTy->getContext(), BasePtrOffset - 1);
+ return ConstantExpr::getIntToPtr(CI, GEPTy);
+ }
}
}
diff --git a/test/Transforms/InstSimplify/compare.ll b/test/Transforms/InstSimplify/compare.ll
index addb63c57222..3e7316ec6b48 100644
--- a/test/Transforms/InstSimplify/compare.ll
+++ b/test/Transforms/InstSimplify/compare.ll
@@ -218,19 +218,6 @@ define i1 @gep17() {
; CHECK-NEXT: ret i1 true
}
-define i32 @gep18() {
-; CHECK-LABEL: @gep18(
- %alloca = alloca i32, align 4 ; alloca + 0
- %gep = getelementptr inbounds i32, i32* %alloca, i32 1 ; alloca + 4
- %bc = bitcast i32* %gep to [4 x i8]* ; alloca + 4
- %pti = ptrtoint i32* %alloca to i32 ; alloca
- %sub = sub i32 0, %pti ; -alloca
- %add = getelementptr [4 x i8], [4 x i8]* %bc, i32 0, i32 %sub ; alloca + 4 - alloca == 4
- %add_to_int = ptrtoint i8* %add to i32 ; 4
- ret i32 %add_to_int ; 4
-; CHECK-NEXT: ret i32 4
-}
-
define i1 @zext(i32 %x) {
; CHECK-LABEL: @zext(
%e1 = zext i32 %x to i64
--
2.7.4