[llvm] [ObjectSizeOffsetVisitor] Add a max recursion depth (PR #67479)
Arthur Eubanks via llvm-commits
llvm-commits at lists.llvm.org
Tue Sep 26 14:08:25 PDT 2023
https://github.com/aeubanks updated https://github.com/llvm/llvm-project/pull/67479
>From 6e42937cc41cf1d2d5ff3d215253dbf4f6b08fc2 Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeubanks at google.com>
Date: Tue, 26 Sep 2023 12:50:08 -0700
Subject: [PATCH 1/4] [ObjectSizeOffsetVisitor] Add a max recursion depth
We're running into stack overflows for huge functions with lots of phis. Even without the stack overflows, this is recursing >7000 in some auto-generated code.
This fixes the stack overflow and brings down the compile time to something reasonable.
---
llvm/include/llvm/Analysis/MemoryBuiltins.h | 1 +
llvm/lib/Analysis/MemoryBuiltins.cpp | 25 ++++++--
...bject-size-offset-visitor-max-recursion.ll | 63 +++++++++++++++++++
3 files changed, 83 insertions(+), 6 deletions(-)
create mode 100644 llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
diff --git a/llvm/include/llvm/Analysis/MemoryBuiltins.h b/llvm/include/llvm/Analysis/MemoryBuiltins.h
index 1d9831889f573ab..49e5b69898427d1 100644
--- a/llvm/include/llvm/Analysis/MemoryBuiltins.h
+++ b/llvm/include/llvm/Analysis/MemoryBuiltins.h
@@ -199,6 +199,7 @@ class ObjectSizeOffsetVisitor
unsigned IntTyBits;
APInt Zero;
SmallDenseMap<Instruction *, SizeOffsetType, 8> SeenInsts;
+ unsigned RecurseDepth = 0;
APInt align(APInt Size, MaybeAlign Align);
diff --git a/llvm/lib/Analysis/MemoryBuiltins.cpp b/llvm/lib/Analysis/MemoryBuiltins.cpp
index 9eab801c3ccbb97..d727e8214dc7938 100644
--- a/llvm/lib/Analysis/MemoryBuiltins.cpp
+++ b/llvm/lib/Analysis/MemoryBuiltins.cpp
@@ -35,6 +35,7 @@
#include "llvm/IR/Type.h"
#include "llvm/IR/Value.h"
#include "llvm/Support/Casting.h"
+#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/raw_ostream.h"
@@ -50,6 +51,12 @@ using namespace llvm;
#define DEBUG_TYPE "memory-builtins"
+static cl::opt<unsigned> ObjectSizeOffsetVisitorMaxRecurseDepth(
+ "object-size-offset-visitor-max-recurse-depth",
+ cl::desc(
+ "Maximum number of PHIs for ObjectSizeOffsetVisitor to look through"),
+ cl::init(100));
+
enum AllocType : uint8_t {
OpNewLike = 1<<0, // allocates; never returns null
MallocLike = 1<<1, // allocates; may return null
@@ -994,14 +1001,20 @@ SizeOffsetType ObjectSizeOffsetVisitor::combineSizeOffset(SizeOffsetType LHS,
}
SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode &PN) {
- if (PN.getNumIncomingValues() == 0)
+ if (PN.getNumIncomingValues() == 0 ||
+ RecurseDepth >= ObjectSizeOffsetVisitorMaxRecurseDepth)
return unknown();
+
+ ++RecurseDepth;
auto IncomingValues = PN.incoming_values();
- return std::accumulate(IncomingValues.begin() + 1, IncomingValues.end(),
- compute(*IncomingValues.begin()),
- [this](SizeOffsetType LHS, Value *VRHS) {
- return combineSizeOffset(LHS, compute(VRHS));
- });
+ SizeOffsetType Ret =
+ std::accumulate(IncomingValues.begin() + 1, IncomingValues.end(),
+ compute(*IncomingValues.begin()),
+ [this](SizeOffsetType LHS, Value *VRHS) {
+ return combineSizeOffset(LHS, compute(VRHS));
+ });
+ --RecurseDepth;
+ return Ret;
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {
diff --git a/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll b/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
new file mode 100644
index 000000000000000..ee6db23f13581d4
--- /dev/null
+++ b/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
@@ -0,0 +1,63 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt -passes=dse -S -object-size-offset-visitor-max-recurse-depth=1 < %s | FileCheck %s --check-prefix=NO
+; RUN: opt -passes=dse -S -object-size-offset-visitor-max-recurse-depth=2 < %s | FileCheck %s --check-prefix=YES
+
+declare void @use(ptr)
+
+define void @f(i32 %i, i1 %c) {
+; NO-LABEL: define void @f(
+; NO-SAME: i32 [[I:%.*]], i1 [[C:%.*]]) {
+; NO-NEXT: b0:
+; NO-NEXT: [[A1:%.*]] = alloca i32, align 4
+; NO-NEXT: [[A2:%.*]] = alloca i32, align 4
+; NO-NEXT: br i1 [[C]], label [[B1:%.*]], label [[B2:%.*]]
+; NO: b1:
+; NO-NEXT: [[A3:%.*]] = phi ptr [ [[A1]], [[B0:%.*]] ]
+; NO-NEXT: br label [[B3:%.*]]
+; NO: b2:
+; NO-NEXT: [[A4:%.*]] = phi ptr [ [[A2]], [[B0]] ]
+; NO-NEXT: br label [[B3]]
+; NO: b3:
+; NO-NEXT: [[A5:%.*]] = phi ptr [ [[A3]], [[B1]] ], [ [[A4]], [[B2]] ]
+; NO-NEXT: [[G:%.*]] = getelementptr i8, ptr [[A5]], i32 [[I]]
+; NO-NEXT: store i8 1, ptr [[G]], align 1
+; NO-NEXT: store i32 0, ptr [[A5]], align 4
+; NO-NEXT: call void @use(ptr [[A5]])
+; NO-NEXT: ret void
+;
+; YES-LABEL: define void @f(
+; YES-SAME: i32 [[I:%.*]], i1 [[C:%.*]]) {
+; YES-NEXT: b0:
+; YES-NEXT: [[A1:%.*]] = alloca i32, align 4
+; YES-NEXT: [[A2:%.*]] = alloca i32, align 4
+; YES-NEXT: br i1 [[C]], label [[B1:%.*]], label [[B2:%.*]]
+; YES: b1:
+; YES-NEXT: [[A3:%.*]] = phi ptr [ [[A1]], [[B0:%.*]] ]
+; YES-NEXT: br label [[B3:%.*]]
+; YES: b2:
+; YES-NEXT: [[A4:%.*]] = phi ptr [ [[A2]], [[B0]] ]
+; YES-NEXT: br label [[B3]]
+; YES: b3:
+; YES-NEXT: [[A5:%.*]] = phi ptr [ [[A3]], [[B1]] ], [ [[A4]], [[B2]] ]
+; YES-NEXT: store i32 0, ptr [[A5]], align 4
+; YES-NEXT: call void @use(ptr [[A5]])
+; YES-NEXT: ret void
+;
+b0:
+ %a1 = alloca i32
+ %a2 = alloca i32
+ br i1 %c, label %b1, label %b2
+b1:
+ %a3 = phi ptr [ %a1, %b0 ]
+ br label %b3
+b2:
+ %a4 = phi ptr [ %a2, %b0 ]
+ br label %b3
+b3:
+ %a5 = phi ptr [ %a3, %b1 ], [ %a4, %b2 ]
+ %g = getelementptr i8, ptr %a5, i32 %i
+ store i8 1, ptr %g
+ store i32 0, ptr %a5
+ call void @use(ptr %a5)
+ ret void
+}
>From 46f553acab2be69f2f991e07cc06a466d3eff5cd Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeubanks at google.com>
Date: Tue, 26 Sep 2023 13:16:48 -0700
Subject: [PATCH 2/4] also check selects, lower max depth to 20
---
llvm/lib/Analysis/MemoryBuiltins.cpp | 11 ++++--
...bject-size-offset-visitor-max-recursion.ll | 37 +++++++++++++++++++
2 files changed, 45 insertions(+), 3 deletions(-)
diff --git a/llvm/lib/Analysis/MemoryBuiltins.cpp b/llvm/lib/Analysis/MemoryBuiltins.cpp
index d727e8214dc7938..f1f3d3f643fa97c 100644
--- a/llvm/lib/Analysis/MemoryBuiltins.cpp
+++ b/llvm/lib/Analysis/MemoryBuiltins.cpp
@@ -55,7 +55,7 @@ static cl::opt<unsigned> ObjectSizeOffsetVisitorMaxRecurseDepth(
"object-size-offset-visitor-max-recurse-depth",
cl::desc(
"Maximum number of PHIs for ObjectSizeOffsetVisitor to look through"),
- cl::init(100));
+ cl::init(20));
enum AllocType : uint8_t {
OpNewLike = 1<<0, // allocates; never returns null
@@ -1018,8 +1018,13 @@ SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode &PN) {
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {
- return combineSizeOffset(compute(I.getTrueValue()),
- compute(I.getFalseValue()));
+ if (RecurseDepth >= ObjectSizeOffsetVisitorMaxRecurseDepth)
+ return unknown();
+ ++RecurseDepth;
+ SizeOffsetType Ret =
+ combineSizeOffset(compute(I.getTrueValue()), compute(I.getFalseValue()));
+ --RecurseDepth;
+ return Ret;
}
SizeOffsetType ObjectSizeOffsetVisitor::visitUndefValue(UndefValue&) {
diff --git a/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll b/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
index ee6db23f13581d4..2339b3803dbbddd 100644
--- a/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
+++ b/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
@@ -61,3 +61,40 @@ b3:
call void @use(ptr %a5)
ret void
}
+
+define void @g(i32 %i, i1 %c1, i1 %c2) {
+; NO-LABEL: define void @g(
+; NO-SAME: i32 [[I:%.*]], i1 [[C1:%.*]], i1 [[C2:%.*]]) {
+; NO-NEXT: [[A1:%.*]] = alloca i32, align 4
+; NO-NEXT: [[A2:%.*]] = alloca i32, align 4
+; NO-NEXT: [[A3:%.*]] = alloca i32, align 4
+; NO-NEXT: [[A4:%.*]] = select i1 [[C1]], ptr [[A1]], ptr [[A2]]
+; NO-NEXT: [[A5:%.*]] = select i1 [[C2]], ptr [[A4]], ptr [[A3]]
+; NO-NEXT: [[G:%.*]] = getelementptr i8, ptr [[A5]], i32 [[I]]
+; NO-NEXT: store i8 1, ptr [[G]], align 1
+; NO-NEXT: store i32 0, ptr [[A5]], align 4
+; NO-NEXT: call void @use(ptr [[A5]])
+; NO-NEXT: ret void
+;
+; YES-LABEL: define void @g(
+; YES-SAME: i32 [[I:%.*]], i1 [[C1:%.*]], i1 [[C2:%.*]]) {
+; YES-NEXT: [[A1:%.*]] = alloca i32, align 4
+; YES-NEXT: [[A2:%.*]] = alloca i32, align 4
+; YES-NEXT: [[A3:%.*]] = alloca i32, align 4
+; YES-NEXT: [[A4:%.*]] = select i1 [[C1]], ptr [[A1]], ptr [[A2]]
+; YES-NEXT: [[A5:%.*]] = select i1 [[C2]], ptr [[A4]], ptr [[A3]]
+; YES-NEXT: store i32 0, ptr [[A5]], align 4
+; YES-NEXT: call void @use(ptr [[A5]])
+; YES-NEXT: ret void
+;
+ %a1 = alloca i32
+ %a2 = alloca i32
+ %a3 = alloca i32
+ %a4 = select i1 %c1, ptr %a1, ptr %a2
+ %a5 = select i1 %c2, ptr %a4, ptr %a3
+ %g = getelementptr i8, ptr %a5, i32 %i
+ store i8 1, ptr %g
+ store i32 0, ptr %a5
+ call void @use(ptr %a5)
+ ret void
+}
>From 8aa386652c0c925c6b3b9d9d17f618eeec749158 Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeubanks at google.com>
Date: Tue, 26 Sep 2023 13:20:08 -0700
Subject: [PATCH 3/4] fix cl::opt description
---
llvm/lib/Analysis/MemoryBuiltins.cpp | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/llvm/lib/Analysis/MemoryBuiltins.cpp b/llvm/lib/Analysis/MemoryBuiltins.cpp
index f1f3d3f643fa97c..51aeb7f0e7fba48 100644
--- a/llvm/lib/Analysis/MemoryBuiltins.cpp
+++ b/llvm/lib/Analysis/MemoryBuiltins.cpp
@@ -53,8 +53,8 @@ using namespace llvm;
static cl::opt<unsigned> ObjectSizeOffsetVisitorMaxRecurseDepth(
"object-size-offset-visitor-max-recurse-depth",
- cl::desc(
- "Maximum number of PHIs for ObjectSizeOffsetVisitor to look through"),
+ cl::desc("Maximum number of PHIs/selects for ObjectSizeOffsetVisitor to "
+ "look through"),
cl::init(20));
enum AllocType : uint8_t {
>From 8ffeef0f454dae3d4875879cbc1525078c7f4ab3 Mon Sep 17 00:00:00 2001
From: Arthur Eubanks <aeubanks at google.com>
Date: Tue, 26 Sep 2023 14:07:12 -0700
Subject: [PATCH 4/4] track all visited instructions
needed to create a new helper function since we need to track InstructionsVisited per call to compute()
---
llvm/include/llvm/Analysis/MemoryBuiltins.h | 3 +-
llvm/lib/Analysis/MemoryBuiltins.cpp | 56 +++++-----
...bject-size-offset-visitor-max-recursion.ll | 100 ------------------
...e-offset-visitor-max-visit-instructions.ll | 51 +++++++++
4 files changed, 80 insertions(+), 130 deletions(-)
delete mode 100644 llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
create mode 100644 llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-visit-instructions.ll
diff --git a/llvm/include/llvm/Analysis/MemoryBuiltins.h b/llvm/include/llvm/Analysis/MemoryBuiltins.h
index 49e5b69898427d1..827b5081b2ce755 100644
--- a/llvm/include/llvm/Analysis/MemoryBuiltins.h
+++ b/llvm/include/llvm/Analysis/MemoryBuiltins.h
@@ -199,7 +199,7 @@ class ObjectSizeOffsetVisitor
unsigned IntTyBits;
APInt Zero;
SmallDenseMap<Instruction *, SizeOffsetType, 8> SeenInsts;
- unsigned RecurseDepth = 0;
+ unsigned InstructionsVisited;
APInt align(APInt Size, MaybeAlign Align);
@@ -249,6 +249,7 @@ class ObjectSizeOffsetVisitor
unsigned &ScannedInstCount);
SizeOffsetType combineSizeOffset(SizeOffsetType LHS, SizeOffsetType RHS);
SizeOffsetType computeImpl(Value *V);
+ SizeOffsetType computeValue(Value *V);
bool CheckedZextOrTrunc(APInt &I);
};
diff --git a/llvm/lib/Analysis/MemoryBuiltins.cpp b/llvm/lib/Analysis/MemoryBuiltins.cpp
index 51aeb7f0e7fba48..6ee1984f908b8a1 100644
--- a/llvm/lib/Analysis/MemoryBuiltins.cpp
+++ b/llvm/lib/Analysis/MemoryBuiltins.cpp
@@ -51,11 +51,11 @@ using namespace llvm;
#define DEBUG_TYPE "memory-builtins"
-static cl::opt<unsigned> ObjectSizeOffsetVisitorMaxRecurseDepth(
- "object-size-offset-visitor-max-recurse-depth",
- cl::desc("Maximum number of PHIs/selects for ObjectSizeOffsetVisitor to "
- "look through"),
- cl::init(20));
+static cl::opt<unsigned> ObjectSizeOffsetVisitorMaxVisitInstructions(
+ "object-size-offset-visitor-max-visit-instructions",
+ cl::desc("Maximum number of instructions for ObjectSizeOffsetVisitor to "
+ "look at"),
+ cl::init(100));
enum AllocType : uint8_t {
OpNewLike = 1<<0, // allocates; never returns null
@@ -701,6 +701,11 @@ ObjectSizeOffsetVisitor::ObjectSizeOffsetVisitor(const DataLayout &DL,
}
SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) {
+ InstructionsVisited = 0;
+ return computeImpl(V);
+}
+
+SizeOffsetType ObjectSizeOffsetVisitor::computeImpl(Value *V) {
unsigned InitialIntTyBits = DL.getIndexTypeSizeInBits(V->getType());
// Stripping pointer casts can strip address space casts which can change the
@@ -717,14 +722,15 @@ SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) {
IntTyBits = DL.getIndexTypeSizeInBits(V->getType());
Zero = APInt::getZero(IntTyBits);
+ SizeOffsetType SOT = computeValue(V);
+
bool IndexTypeSizeChanged = InitialIntTyBits != IntTyBits;
if (!IndexTypeSizeChanged && Offset.isZero())
- return computeImpl(V);
+ return SOT;
// We stripped an address space cast that changed the index type size or we
// accumulated some constant offset (or both). Readjust the bit width to match
// the argument index type size and apply the offset, as required.
- SizeOffsetType SOT = computeImpl(V);
if (IndexTypeSizeChanged) {
if (knownSize(SOT) && !::CheckedZextOrTrunc(SOT.first, InitialIntTyBits))
SOT.first = APInt();
@@ -736,13 +742,16 @@ SizeOffsetType ObjectSizeOffsetVisitor::compute(Value *V) {
SOT.second.getBitWidth() > 1 ? SOT.second + Offset : SOT.second};
}
-SizeOffsetType ObjectSizeOffsetVisitor::computeImpl(Value *V) {
+SizeOffsetType ObjectSizeOffsetVisitor::computeValue(Value *V) {
if (Instruction *I = dyn_cast<Instruction>(V)) {
// If we have already seen this instruction, bail out. Cycles can happen in
// unreachable code after constant propagation.
auto P = SeenInsts.try_emplace(I, unknown());
if (!P.second)
return P.first->second;
+ ++InstructionsVisited;
+ if (InstructionsVisited > ObjectSizeOffsetVisitorMaxVisitInstructions)
+ return unknown();
SizeOffsetType Res = visit(*I);
// Cache the result for later visits. If we happened to visit this during
// the above recursion, we would consider it unknown until now.
@@ -837,7 +846,7 @@ ObjectSizeOffsetVisitor::visitExtractValueInst(ExtractValueInst&) {
SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalAlias(GlobalAlias &GA) {
if (GA.isInterposable())
return unknown();
- return compute(GA.getAliasee());
+ return computeImpl(GA.getAliasee());
}
SizeOffsetType ObjectSizeOffsetVisitor::visitGlobalVariable(GlobalVariable &GV){
@@ -892,7 +901,7 @@ SizeOffsetType ObjectSizeOffsetVisitor::findLoadSizeOffset(
continue;
case AliasResult::MustAlias:
if (SI->getValueOperand()->getType()->isPointerTy())
- return Known(compute(SI->getValueOperand()));
+ return Known(computeImpl(SI->getValueOperand()));
else
return Unknown(); // No handling of non-pointer values by `compute`.
default:
@@ -1001,30 +1010,19 @@ SizeOffsetType ObjectSizeOffsetVisitor::combineSizeOffset(SizeOffsetType LHS,
}
SizeOffsetType ObjectSizeOffsetVisitor::visitPHINode(PHINode &PN) {
- if (PN.getNumIncomingValues() == 0 ||
- RecurseDepth >= ObjectSizeOffsetVisitorMaxRecurseDepth)
+ if (PN.getNumIncomingValues() == 0)
return unknown();
-
- ++RecurseDepth;
auto IncomingValues = PN.incoming_values();
- SizeOffsetType Ret =
- std::accumulate(IncomingValues.begin() + 1, IncomingValues.end(),
- compute(*IncomingValues.begin()),
- [this](SizeOffsetType LHS, Value *VRHS) {
- return combineSizeOffset(LHS, compute(VRHS));
- });
- --RecurseDepth;
- return Ret;
+ return std::accumulate(IncomingValues.begin() + 1, IncomingValues.end(),
+ computeImpl(*IncomingValues.begin()),
+ [this](SizeOffsetType LHS, Value *VRHS) {
+ return combineSizeOffset(LHS, computeImpl(VRHS));
+ });
}
SizeOffsetType ObjectSizeOffsetVisitor::visitSelectInst(SelectInst &I) {
- if (RecurseDepth >= ObjectSizeOffsetVisitorMaxRecurseDepth)
- return unknown();
- ++RecurseDepth;
- SizeOffsetType Ret =
- combineSizeOffset(compute(I.getTrueValue()), compute(I.getFalseValue()));
- --RecurseDepth;
- return Ret;
+ return combineSizeOffset(computeImpl(I.getTrueValue()),
+ computeImpl(I.getFalseValue()));
}
SizeOffsetType ObjectSizeOffsetVisitor::visitUndefValue(UndefValue&) {
diff --git a/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll b/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
deleted file mode 100644
index 2339b3803dbbddd..000000000000000
--- a/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-recursion.ll
+++ /dev/null
@@ -1,100 +0,0 @@
-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
-; RUN: opt -passes=dse -S -object-size-offset-visitor-max-recurse-depth=1 < %s | FileCheck %s --check-prefix=NO
-; RUN: opt -passes=dse -S -object-size-offset-visitor-max-recurse-depth=2 < %s | FileCheck %s --check-prefix=YES
-
-declare void @use(ptr)
-
-define void @f(i32 %i, i1 %c) {
-; NO-LABEL: define void @f(
-; NO-SAME: i32 [[I:%.*]], i1 [[C:%.*]]) {
-; NO-NEXT: b0:
-; NO-NEXT: [[A1:%.*]] = alloca i32, align 4
-; NO-NEXT: [[A2:%.*]] = alloca i32, align 4
-; NO-NEXT: br i1 [[C]], label [[B1:%.*]], label [[B2:%.*]]
-; NO: b1:
-; NO-NEXT: [[A3:%.*]] = phi ptr [ [[A1]], [[B0:%.*]] ]
-; NO-NEXT: br label [[B3:%.*]]
-; NO: b2:
-; NO-NEXT: [[A4:%.*]] = phi ptr [ [[A2]], [[B0]] ]
-; NO-NEXT: br label [[B3]]
-; NO: b3:
-; NO-NEXT: [[A5:%.*]] = phi ptr [ [[A3]], [[B1]] ], [ [[A4]], [[B2]] ]
-; NO-NEXT: [[G:%.*]] = getelementptr i8, ptr [[A5]], i32 [[I]]
-; NO-NEXT: store i8 1, ptr [[G]], align 1
-; NO-NEXT: store i32 0, ptr [[A5]], align 4
-; NO-NEXT: call void @use(ptr [[A5]])
-; NO-NEXT: ret void
-;
-; YES-LABEL: define void @f(
-; YES-SAME: i32 [[I:%.*]], i1 [[C:%.*]]) {
-; YES-NEXT: b0:
-; YES-NEXT: [[A1:%.*]] = alloca i32, align 4
-; YES-NEXT: [[A2:%.*]] = alloca i32, align 4
-; YES-NEXT: br i1 [[C]], label [[B1:%.*]], label [[B2:%.*]]
-; YES: b1:
-; YES-NEXT: [[A3:%.*]] = phi ptr [ [[A1]], [[B0:%.*]] ]
-; YES-NEXT: br label [[B3:%.*]]
-; YES: b2:
-; YES-NEXT: [[A4:%.*]] = phi ptr [ [[A2]], [[B0]] ]
-; YES-NEXT: br label [[B3]]
-; YES: b3:
-; YES-NEXT: [[A5:%.*]] = phi ptr [ [[A3]], [[B1]] ], [ [[A4]], [[B2]] ]
-; YES-NEXT: store i32 0, ptr [[A5]], align 4
-; YES-NEXT: call void @use(ptr [[A5]])
-; YES-NEXT: ret void
-;
-b0:
- %a1 = alloca i32
- %a2 = alloca i32
- br i1 %c, label %b1, label %b2
-b1:
- %a3 = phi ptr [ %a1, %b0 ]
- br label %b3
-b2:
- %a4 = phi ptr [ %a2, %b0 ]
- br label %b3
-b3:
- %a5 = phi ptr [ %a3, %b1 ], [ %a4, %b2 ]
- %g = getelementptr i8, ptr %a5, i32 %i
- store i8 1, ptr %g
- store i32 0, ptr %a5
- call void @use(ptr %a5)
- ret void
-}
-
-define void @g(i32 %i, i1 %c1, i1 %c2) {
-; NO-LABEL: define void @g(
-; NO-SAME: i32 [[I:%.*]], i1 [[C1:%.*]], i1 [[C2:%.*]]) {
-; NO-NEXT: [[A1:%.*]] = alloca i32, align 4
-; NO-NEXT: [[A2:%.*]] = alloca i32, align 4
-; NO-NEXT: [[A3:%.*]] = alloca i32, align 4
-; NO-NEXT: [[A4:%.*]] = select i1 [[C1]], ptr [[A1]], ptr [[A2]]
-; NO-NEXT: [[A5:%.*]] = select i1 [[C2]], ptr [[A4]], ptr [[A3]]
-; NO-NEXT: [[G:%.*]] = getelementptr i8, ptr [[A5]], i32 [[I]]
-; NO-NEXT: store i8 1, ptr [[G]], align 1
-; NO-NEXT: store i32 0, ptr [[A5]], align 4
-; NO-NEXT: call void @use(ptr [[A5]])
-; NO-NEXT: ret void
-;
-; YES-LABEL: define void @g(
-; YES-SAME: i32 [[I:%.*]], i1 [[C1:%.*]], i1 [[C2:%.*]]) {
-; YES-NEXT: [[A1:%.*]] = alloca i32, align 4
-; YES-NEXT: [[A2:%.*]] = alloca i32, align 4
-; YES-NEXT: [[A3:%.*]] = alloca i32, align 4
-; YES-NEXT: [[A4:%.*]] = select i1 [[C1]], ptr [[A1]], ptr [[A2]]
-; YES-NEXT: [[A5:%.*]] = select i1 [[C2]], ptr [[A4]], ptr [[A3]]
-; YES-NEXT: store i32 0, ptr [[A5]], align 4
-; YES-NEXT: call void @use(ptr [[A5]])
-; YES-NEXT: ret void
-;
- %a1 = alloca i32
- %a2 = alloca i32
- %a3 = alloca i32
- %a4 = select i1 %c1, ptr %a1, ptr %a2
- %a5 = select i1 %c2, ptr %a4, ptr %a3
- %g = getelementptr i8, ptr %a5, i32 %i
- store i8 1, ptr %g
- store i32 0, ptr %a5
- call void @use(ptr %a5)
- ret void
-}
diff --git a/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-visit-instructions.ll b/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-visit-instructions.ll
new file mode 100644
index 000000000000000..b94ff6289588284
--- /dev/null
+++ b/llvm/test/Transforms/DeadStoreElimination/object-size-offset-visitor-max-visit-instructions.ll
@@ -0,0 +1,51 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 3
+; RUN: opt -passes=dse -S -object-size-offset-visitor-max-visit-instructions=2 < %s | FileCheck %s --check-prefix=NO
+; RUN: opt -passes=dse -S -object-size-offset-visitor-max-visit-instructions=3 < %s | FileCheck %s --check-prefix=YES
+
+declare void @use(ptr)
+
+define void @f(i32 %i, i1 %c) {
+; NO-LABEL: define void @f(
+; NO-SAME: i32 [[I:%.*]], i1 [[C:%.*]]) {
+; NO-NEXT: b0:
+; NO-NEXT: [[A1:%.*]] = alloca i32, align 4
+; NO-NEXT: [[A2:%.*]] = alloca i32, align 4
+; NO-NEXT: br i1 [[C]], label [[B1:%.*]], label [[B2:%.*]]
+; NO: b1:
+; NO-NEXT: br label [[B2]]
+; NO: b2:
+; NO-NEXT: [[A5:%.*]] = phi ptr [ [[A1]], [[B0:%.*]] ], [ [[A2]], [[B1]] ]
+; NO-NEXT: [[G:%.*]] = getelementptr i8, ptr [[A5]], i32 [[I]]
+; NO-NEXT: store i8 1, ptr [[G]], align 1
+; NO-NEXT: store i32 0, ptr [[A5]], align 4
+; NO-NEXT: call void @use(ptr [[A5]])
+; NO-NEXT: ret void
+;
+; YES-LABEL: define void @f(
+; YES-SAME: i32 [[I:%.*]], i1 [[C:%.*]]) {
+; YES-NEXT: b0:
+; YES-NEXT: [[A1:%.*]] = alloca i32, align 4
+; YES-NEXT: [[A2:%.*]] = alloca i32, align 4
+; YES-NEXT: br i1 [[C]], label [[B1:%.*]], label [[B2:%.*]]
+; YES: b1:
+; YES-NEXT: br label [[B2]]
+; YES: b2:
+; YES-NEXT: [[A5:%.*]] = phi ptr [ [[A1]], [[B0:%.*]] ], [ [[A2]], [[B1]] ]
+; YES-NEXT: store i32 0, ptr [[A5]], align 4
+; YES-NEXT: call void @use(ptr [[A5]])
+; YES-NEXT: ret void
+;
+b0:
+ %a1 = alloca i32
+ %a2 = alloca i32
+ br i1 %c, label %b1, label %b2
+b1:
+ br label %b2
+b2:
+ %a5 = phi ptr [ %a1, %b0 ], [ %a2, %b1 ]
+ %g = getelementptr i8, ptr %a5, i32 %i
+ store i8 1, ptr %g
+ store i32 0, ptr %a5
+ call void @use(ptr %a5)
+ ret void
+}
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