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Rollback of rL355585.
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Introduces memory leak in FunctionTest.GetPointerAlignment that breaks sanitizer buildbots:

```
=================================================================
==2453==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 128 byte(s) in 1 object(s) allocated from:
    #0 0x610428 in operator new(unsigned long) /b/sanitizer-x86_64-linux-bootstrap/build/llvm/projects/compiler-rt/lib/asan/asan_new_delete.cc:105
    #1 0x16936bc in llvm::User::operator new(unsigned long) /b/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/IR/User.cpp:151:19
    #2 0x7c3fe9 in Create /b/sanitizer-x86_64-linux-bootstrap/build/llvm/include/llvm/IR/Function.h:144:12
    #3 0x7c3fe9 in (anonymous namespace)::FunctionTest_GetPointerAlignment_Test::TestBody() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/unittests/IR/FunctionTest.cpp:136
    #4 0x1a836a0 in HandleExceptionsInMethodIfSupported<testing::Test, void> /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc
    #5 0x1a836a0 in testing::Test::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:2474
    #6 0x1a85c55 in testing::TestInfo::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:2656:11
    #7 0x1a870d0 in testing::TestCase::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:2774:28
    #8 0x1aa5b84 in testing::internal::UnitTestImpl::RunAllTests() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:4649:43
    #9 0x1aa4d30 in HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool> /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc
    #10 0x1aa4d30 in testing::UnitTest::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:4257
    #11 0x1a6b656 in RUN_ALL_TESTS /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/include/gtest/gtest.h:2233:46
    #12 0x1a6b656 in main /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/UnitTestMain/TestMain.cpp:50
    #13 0x7f5af37a22e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)

Indirect leak of 40 byte(s) in 1 object(s) allocated from:
    #0 0x610428 in operator new(unsigned long) /b/sanitizer-x86_64-linux-bootstrap/build/llvm/projects/compiler-rt/lib/asan/asan_new_delete.cc:105
    #1 0x151be6b in make_unique<llvm::ValueSymbolTable> /b/sanitizer-x86_64-linux-bootstrap/build/llvm/include/llvm/ADT/STLExtras.h:1349:29
    #2 0x151be6b in llvm::Function::Function(llvm::FunctionType*, llvm::GlobalValue::LinkageTypes, unsigned int, llvm::Twine const&, llvm::Module*) /b/sanitizer-x86_64-linux-bootstrap/build/llvm/lib/IR/Function.cpp:241
    #3 0x7c4006 in Create /b/sanitizer-x86_64-linux-bootstrap/build/llvm/include/llvm/IR/Function.h:144:16
    #4 0x7c4006 in (anonymous namespace)::FunctionTest_GetPointerAlignment_Test::TestBody() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/unittests/IR/FunctionTest.cpp:136
    #5 0x1a836a0 in HandleExceptionsInMethodIfSupported<testing::Test, void> /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc
    #6 0x1a836a0 in testing::Test::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:2474
    #7 0x1a85c55 in testing::TestInfo::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:2656:11
    #8 0x1a870d0 in testing::TestCase::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:2774:28
    #9 0x1aa5b84 in testing::internal::UnitTestImpl::RunAllTests() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:4649:43
    #10 0x1aa4d30 in HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool> /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc
    #11 0x1aa4d30 in testing::UnitTest::Run() /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/src/gtest.cc:4257
    #12 0x1a6b656 in RUN_ALL_TESTS /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/googletest/include/gtest/gtest.h:2233:46
    #13 0x1a6b656 in main /b/sanitizer-x86_64-linux-bootstrap/build/llvm/utils/unittest/UnitTestMain/TestMain.cpp:50
    #14 0x7f5af37a22e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)

SUMMARY: AddressSanitizer: 168 byte(s) leaked in 2 allocation(s).
```

See http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-bootstrap/builds/11358/steps/check-llvm%20asan/logs/stdio for more information.

Also introduces use-of-uninitialized-value in ConstantsTest.FoldGlobalVariablePtr:
```
==7070==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x14e703c in User /b/sanitizer-x86_64-linux-fast/build/llvm/include/llvm/IR/User.h:79:5
    #1 0x14e703c in Constant /b/sanitizer-x86_64-linux-fast/build/llvm/include/llvm/IR/Constant.h:44
    #2 0x14e703c in llvm::GlobalValue::GlobalValue(llvm::Type*, llvm::Value::ValueTy, llvm::Use*, unsigned int, llvm::GlobalValue::LinkageTypes, llvm::Twine const&, unsigned int) /b/sanitizer-x86_64-linux-fast/build/llvm/include/llvm/IR/GlobalValue.h:78
    #3 0x14e5467 in GlobalObject /b/sanitizer-x86_64-linux-fast/build/llvm/include/llvm/IR/GlobalObject.h:34:9
    #4 0x14e5467 in llvm::GlobalVariable::GlobalVariable(llvm::Type*, bool, llvm::GlobalValue::LinkageTypes, llvm::Constant*, llvm::Twine const&, llvm::GlobalValue::ThreadLocalMode, unsigned int, bool) /b/sanitizer-x86_64-linux-fast/build/llvm/lib/IR/Globals.cpp:314
    #5 0x6938f1 in llvm::(anonymous namespace)::ConstantsTest_FoldGlobalVariablePtr_Test::TestBody() /b/sanitizer-x86_64-linux-fast/build/llvm/unittests/IR/ConstantsTest.cpp:565:18
    #6 0x1a240a1 in HandleExceptionsInMethodIfSupported<testing::Test, void> /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/src/gtest.cc
    #7 0x1a240a1 in testing::Test::Run() /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/src/gtest.cc:2474
    #8 0x1a26d26 in testing::TestInfo::Run() /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/src/gtest.cc:2656:11
    #9 0x1a2815f in testing::TestCase::Run() /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/src/gtest.cc:2774:28
    #10 0x1a43de8 in testing::internal::UnitTestImpl::RunAllTests() /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/src/gtest.cc:4649:43
    #11 0x1a42c47 in HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool> /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/src/gtest.cc
    #12 0x1a42c47 in testing::UnitTest::Run() /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/src/gtest.cc:4257
    #13 0x1a0dfba in RUN_ALL_TESTS /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/googletest/include/gtest/gtest.h:2233:46
    #14 0x1a0dfba in main /b/sanitizer-x86_64-linux-fast/build/llvm/utils/unittest/UnitTestMain/TestMain.cpp:50
    #15 0x7f2081c412e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
    #16 0x4dff49 in _start (/b/sanitizer-x86_64-linux-fast/build/llvm_build_msan/unittests/IR/IRTests+0x4dff49)

SUMMARY: MemorySanitizer: use-of-uninitialized-value /b/sanitizer-x86_64-linux-fast/build/llvm/include/llvm/IR/User.h:79:5 in User
```

See http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/30222/steps/check-llvm%20msan/logs/stdio for more information.

llvm-svn: 355616
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@hctim
hctim committed Mar 7, 2019
1 parent 2f94dce commit 92dd321
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Showing 13 changed files with 25 additions and 279 deletions.
23 changes: 11 additions & 12 deletions clang/lib/Basic/Targets/ARM.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -40,26 +40,25 @@ void ARMTargetInfo::setABIAAPCS() {
// so set preferred for small types to 32.
if (T.isOSBinFormatMachO()) {
resetDataLayout(BigEndian
? "E-m:o-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
: "e-m:o-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64");
? "E-m:o-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
: "e-m:o-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64");
} else if (T.isOSWindows()) {
assert(!BigEndian && "Windows on ARM does not support big endian");
resetDataLayout("e"
"-m:w"
"-p:32:32"
"-Fi8"
"-i64:64"
"-v128:64:128"
"-a:0:32"
"-n32"
"-S64");
} else if (T.isOSNaCl()) {
assert(!BigEndian && "NaCl on ARM does not support big endian");
resetDataLayout("e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S128");
resetDataLayout("e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S128");
} else {
resetDataLayout(BigEndian
? "E-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64");
? "E-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"
: "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64");
}

// FIXME: Enumerated types are variable width in straight AAPCS.
Expand Down Expand Up @@ -88,17 +87,17 @@ void ARMTargetInfo::setABIAPCS(bool IsAAPCS16) {

if (T.isOSBinFormatMachO() && IsAAPCS16) {
assert(!BigEndian && "AAPCS16 does not support big-endian");
resetDataLayout("e-m:o-p:32:32-Fi8-i64:64-a:0:32-n32-S128");
resetDataLayout("e-m:o-p:32:32-i64:64-a:0:32-n32-S128");
} else if (T.isOSBinFormatMachO())
resetDataLayout(
BigEndian
? "E-m:o-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
: "e-m:o-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32");
? "E-m:o-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
: "e-m:o-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32");
else
resetDataLayout(
BigEndian
? "E-m:e-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
: "e-m:e-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32");
? "E-m:e-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
: "e-m:e-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32");

// FIXME: Override "preferred align" for double and long long.
}
Expand Down Expand Up @@ -1056,7 +1055,7 @@ CygwinARMTargetInfo::CygwinARMTargetInfo(const llvm::Triple &Triple,
this->WCharType = TargetInfo::UnsignedShort;
TLSSupported = false;
DoubleAlign = LongLongAlign = 64;
resetDataLayout("e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64");
resetDataLayout("e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64");
}

void CygwinARMTargetInfo::getTargetDefines(const LangOptions &Opts,
Expand Down
2 changes: 1 addition & 1 deletion clang/test/CodeGen/armv7k-abi.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -4,7 +4,7 @@

// Make sure 64 and 128 bit types are naturally aligned by the v7k ABI:

// CHECK: target datalayout = "e-m:o-p:32:32-Fi8-i64:64-a:0:32-n32-S128"
// CHECK: target datalayout = "e-m:o-p:32:32-i64:64-a:0:32-n32-S128"

typedef struct {
float arr[4];
Expand Down
10 changes: 5 additions & 5 deletions clang/test/CodeGen/target-data.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -96,7 +96,7 @@

// RUN: %clang_cc1 -triple arm-nacl -o - -emit-llvm %s | \
// RUN: FileCheck %s -check-prefix=ARM-NACL
// ARM-NACL: target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S128"
// ARM-NACL: target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S128"

// RUN: %clang_cc1 -triple mipsel-nacl -o - -emit-llvm %s | \
// RUN: FileCheck %s -check-prefix=MIPS-NACL
Expand Down Expand Up @@ -165,19 +165,19 @@

// RUN: %clang_cc1 -triple thumb-unknown-gnueabi -o - -emit-llvm %s | \
// RUN: FileCheck %s -check-prefix=THUMB
// THUMB: target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
// THUMB: target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"

// RUN: %clang_cc1 -triple arm-unknown-gnueabi -o - -emit-llvm %s | \
// RUN: FileCheck %s -check-prefix=ARM
// ARM: target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
// ARM: target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64"

// RUN: %clang_cc1 -triple thumb-unknown -o - -emit-llvm -target-abi apcs-gnu \
// RUN: %s | FileCheck %s -check-prefix=THUMB-GNU
// THUMB-GNU: target datalayout = "e-m:e-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
// THUMB-GNU: target datalayout = "e-m:e-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"

// RUN: %clang_cc1 -triple arm-unknown -o - -emit-llvm -target-abi apcs-gnu \
// RUN: %s | FileCheck %s -check-prefix=ARM-GNU
// ARM-GNU: target datalayout = "e-m:e-p:32:32-Fi8-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"
// ARM-GNU: target datalayout = "e-m:e-p:32:32-f64:32:64-v64:32:64-v128:32:128-a:0:32-n32-S32"

// RUN: %clang_cc1 -triple arc-unknown-unknown -o - -emit-llvm %s | \
// RUN: FileCheck %s -check-prefix=ARC
Expand Down
8 changes: 0 additions & 8 deletions llvm/docs/LangRef.rst
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2004,14 +2004,6 @@ as follows:
targets.
``a:<abi>:<pref>``
This specifies the alignment for an object of aggregate type.
``F<type><abi>``
This specifies the alignment for function pointers.
The options for ``<type>`` are:

* ``i``: The alignment of function pointers is independent of the alignment
of functions, and is a multiple of ``<abi>``.
* ``n``: The alignment of function pointers is a multiple of the explicit
alignment specified on the function, and is a multiple of ``<abi>``.
``m:<mangling>``
If present, specifies that llvm names are mangled in the output. Symbols
prefixed with the mangling escape character ``\01`` are passed through
Expand Down
23 changes: 0 additions & 23 deletions llvm/include/llvm/IR/DataLayout.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -108,13 +108,6 @@ struct PointerAlignElem {
/// generating LLVM IR is required to generate the right target data for the
/// target being codegen'd to.
class DataLayout {
public:
enum class FunctionPtrAlignType {
/// The function pointer alignment is independent of the function alignment.
Independent,
/// The function pointer alignment is a multiple of the function alignment.
MultipleOfFunctionAlign,
};
private:
/// Defaults to false.
bool BigEndian;
Expand All @@ -123,9 +116,6 @@ class DataLayout {
unsigned StackNaturalAlign;
unsigned ProgramAddrSpace;

unsigned FunctionPtrAlign;
FunctionPtrAlignType TheFunctionPtrAlignType;

enum ManglingModeT {
MM_None,
MM_ELF,
Expand Down Expand Up @@ -209,8 +199,6 @@ class DataLayout {
BigEndian = DL.isBigEndian();
AllocaAddrSpace = DL.AllocaAddrSpace;
StackNaturalAlign = DL.StackNaturalAlign;
FunctionPtrAlign = DL.FunctionPtrAlign;
TheFunctionPtrAlignType = DL.TheFunctionPtrAlignType;
ProgramAddrSpace = DL.ProgramAddrSpace;
ManglingMode = DL.ManglingMode;
LegalIntWidths = DL.LegalIntWidths;
Expand Down Expand Up @@ -268,17 +256,6 @@ class DataLayout {
unsigned getStackAlignment() const { return StackNaturalAlign; }
unsigned getAllocaAddrSpace() const { return AllocaAddrSpace; }

/// Returns the alignment of function pointers, which may or may not be
/// related to the alignment of functions.
/// \see getFunctionPtrAlignType
unsigned getFunctionPtrAlign() const { return FunctionPtrAlign; }

/// Return the type of function pointer alignment.
/// \see getFunctionPtrAlign
FunctionPtrAlignType getFunctionPtrAlignType() const {
return TheFunctionPtrAlignType;
}

unsigned getProgramAddressSpace() const { return ProgramAddrSpace; }

bool hasMicrosoftFastStdCallMangling() const {
Expand Down
28 changes: 4 additions & 24 deletions llvm/lib/IR/ConstantFold.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -26,7 +26,6 @@
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Operator.h"
#include "llvm/IR/PatternMatch.h"
#include "llvm/Support/ErrorHandling.h"
Expand Down Expand Up @@ -1077,29 +1076,10 @@ Constant *llvm::ConstantFoldBinaryInstruction(unsigned Opcode, Constant *C1,
isa<GlobalValue>(CE1->getOperand(0))) {
GlobalValue *GV = cast<GlobalValue>(CE1->getOperand(0));

unsigned GVAlign;

if (Module *TheModule = GV->getParent()) {
GVAlign = GV->getPointerAlignment(TheModule->getDataLayout());

// If the function alignment is not specified then assume that it
// is 4.
// This is dangerous; on x86, the alignment of the pointer
// corresponds to the alignment of the function, but might be less
// than 4 if it isn't explicitly specified.
// However, a fix for this behaviour was reverted because it
// increased code size (see https://reviews.llvm.org/D55115)
// FIXME: This code should be deleted once existing targets have
// appropriate defaults
if (GVAlign == 0U && isa<Function>(GV))
GVAlign = 4U;
} else if (isa<Function>(GV)) {
// Without a datalayout we have to assume the worst case: that the
// function pointer isn't aligned at all.
GVAlign = 0U;
} else {
GVAlign = GV->getAlignment();
}
// Functions are at least 4-byte aligned.
unsigned GVAlign = GV->getAlignment();
if (isa<Function>(GV))
GVAlign = std::max(GVAlign, 4U);

if (GVAlign > 1) {
unsigned DstWidth = CI2->getType()->getBitWidth();
Expand Down
20 changes: 0 additions & 20 deletions llvm/lib/IR/DataLayout.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -184,8 +184,6 @@ void DataLayout::reset(StringRef Desc) {
AllocaAddrSpace = 0;
StackNaturalAlign = 0;
ProgramAddrSpace = 0;
FunctionPtrAlign = 0;
TheFunctionPtrAlignType = FunctionPtrAlignType::Independent;
ManglingMode = MM_None;
NonIntegralAddressSpaces.clear();

Expand Down Expand Up @@ -381,22 +379,6 @@ void DataLayout::parseSpecifier(StringRef Desc) {
StackNaturalAlign = inBytes(getInt(Tok));
break;
}
case 'F': {
switch (Tok.front()) {
case 'i':
TheFunctionPtrAlignType = FunctionPtrAlignType::Independent;
break;
case 'n':
TheFunctionPtrAlignType = FunctionPtrAlignType::MultipleOfFunctionAlign;
break;
default:
report_fatal_error("Unknown function pointer alignment type in "
"datalayout string");
}
Tok = Tok.substr(1);
FunctionPtrAlign = inBytes(getInt(Tok));
break;
}
case 'P': { // Function address space.
ProgramAddrSpace = getAddrSpace(Tok);
break;
Expand Down Expand Up @@ -450,8 +432,6 @@ bool DataLayout::operator==(const DataLayout &Other) const {
AllocaAddrSpace == Other.AllocaAddrSpace &&
StackNaturalAlign == Other.StackNaturalAlign &&
ProgramAddrSpace == Other.ProgramAddrSpace &&
FunctionPtrAlign == Other.FunctionPtrAlign &&
TheFunctionPtrAlignType == Other.TheFunctionPtrAlignType &&
ManglingMode == Other.ManglingMode &&
LegalIntWidths == Other.LegalIntWidths &&
Alignments == Other.Alignments && Pointers == Other.Pointers;
Expand Down
12 changes: 4 additions & 8 deletions llvm/lib/IR/Value.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -648,14 +648,10 @@ unsigned Value::getPointerAlignment(const DataLayout &DL) const {

unsigned Align = 0;
if (auto *GO = dyn_cast<GlobalObject>(this)) {
if (isa<Function>(GO)) {
switch (DL.getFunctionPtrAlignType()) {
case DataLayout::FunctionPtrAlignType::Independent:
return DL.getFunctionPtrAlign();
case DataLayout::FunctionPtrAlignType::MultipleOfFunctionAlign:
return std::max(DL.getFunctionPtrAlign(), GO->getAlignment());
}
}
// Don't make any assumptions about function pointer alignment. Some
// targets use the LSBs to store additional information.
if (isa<Function>(GO))
return 0;
Align = GO->getAlignment();
if (Align == 0) {
if (auto *GVar = dyn_cast<GlobalVariable>(GO)) {
Expand Down
4 changes: 0 additions & 4 deletions llvm/lib/Target/ARM/ARMTargetMachine.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -141,10 +141,6 @@ static std::string computeDataLayout(const Triple &TT, StringRef CPU,
// Pointers are 32 bits and aligned to 32 bits.
Ret += "-p:32:32";

// Function pointers are aligned to 8 bits (because the LSB stores the
// ARM/Thumb state).
Ret += "-Fi8";

// ABIs other than APCS have 64 bit integers with natural alignment.
if (ABI != ARMBaseTargetMachine::ARM_ABI_APCS)
Ret += "-i64:64";
Expand Down
1 change: 0 additions & 1 deletion llvm/unittests/IR/CMakeLists.txt
View file
Original file line number Diff line number Diff line change
Expand Up @@ -13,7 +13,6 @@ add_llvm_unittest(IRTests
CFGBuilder.cpp
ConstantRangeTest.cpp
ConstantsTest.cpp
DataLayoutTest.cpp
DebugInfoTest.cpp
DebugTypeODRUniquingTest.cpp
DominatorTreeTest.cpp
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101 changes: 0 additions & 101 deletions llvm/unittests/IR/ConstantsTest.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -475,106 +475,5 @@ TEST(ConstantsTest, BitcastToGEP) {
ASSERT_EQ(cast<ConstantExpr>(C)->getOpcode(), Instruction::BitCast);
}

bool foldFuncPtrAndConstToNull(LLVMContext &Context, Module *TheModule,
uint64_t AndValue, unsigned FunctionAlign = 0) {
Type *VoidType(Type::getVoidTy(Context));
FunctionType *FuncType(FunctionType::get(VoidType, false));
Function *Func(Function::Create(
FuncType, GlobalValue::ExternalLinkage, "", TheModule));

if (FunctionAlign) Func->setAlignment(FunctionAlign);

IntegerType *ConstantIntType(Type::getInt32Ty(Context));
ConstantInt *TheConstant(ConstantInt::get(ConstantIntType, AndValue));

Constant *TheConstantExpr(
ConstantExpr::getPtrToInt(Func, ConstantIntType));

return ConstantExpr::get(Instruction::And, TheConstantExpr,
TheConstant)->isNullValue();
}

TEST(ConstantsTest, FoldFunctionPtrAlignUnknownAnd2) {
LLVMContext Context;
Module TheModule("TestModule", Context);
// When the DataLayout doesn't specify a function pointer alignment we
// assume in this case that it is 4 byte aligned. This is a bug but we can't
// fix it directly because it causes a code size regression on X86.
// FIXME: This test should be changed once existing targets have
// appropriate defaults. See associated FIXME in ConstantFoldBinaryInstruction
ASSERT_TRUE(foldFuncPtrAndConstToNull(Context, &TheModule, 2));
}

TEST(ConstantsTest, DontFoldFunctionPtrAlignUnknownAnd4) {
LLVMContext Context;
Module TheModule("TestModule", Context);
ASSERT_FALSE(foldFuncPtrAndConstToNull(Context, &TheModule, 4));
}

TEST(ConstantsTest, FoldFunctionPtrAlign4) {
LLVMContext Context;
Module TheModule("TestModule", Context);
const char* AlignmentStrings[] = { "Fi32", "Fn32" };

for (unsigned AndValue = 1; AndValue <= 2; ++AndValue) {
for (const char *AlignmentString : AlignmentStrings) {
TheModule.setDataLayout(AlignmentString);
ASSERT_TRUE(foldFuncPtrAndConstToNull(Context, &TheModule, AndValue));
}
}
}

TEST(ConstantsTest, DontFoldFunctionPtrAlign1) {
LLVMContext Context;
Module TheModule("TestModule", Context);
const char* AlignmentStrings[] = { "Fi8", "Fn8" };

for (const char* AlignmentString : AlignmentStrings) {
TheModule.setDataLayout(AlignmentString);
ASSERT_FALSE(foldFuncPtrAndConstToNull(Context, &TheModule, 2));
}
}

TEST(ConstantsTest, FoldFunctionAlign4PtrAlignMultiple) {
LLVMContext Context;
Module TheModule("TestModule", Context);
TheModule.setDataLayout("Fn8");
ASSERT_TRUE(foldFuncPtrAndConstToNull(Context, &TheModule, 2, 4));
}

TEST(ConstantsTest, DontFoldFunctionAlign4PtrAlignIndependent) {
LLVMContext Context;
Module TheModule("TestModule", Context);
TheModule.setDataLayout("Fi8");
ASSERT_FALSE(foldFuncPtrAndConstToNull(Context, &TheModule, 2, 4));
}

TEST(ConstantsTest, DontFoldFunctionPtrIfNoModule) {
LLVMContext Context;
// Even though the function is explicitly 4 byte aligned, in the absence of a
// DataLayout we can't assume that the function pointer is aligned.
ASSERT_FALSE(foldFuncPtrAndConstToNull(Context, nullptr, 2, 4));
}

TEST(ConstantsTest, FoldGlobalVariablePtr) {
LLVMContext Context;


IntegerType *IntType(Type::getInt32Ty(Context));

std::unique_ptr<GlobalVariable> Global(
new GlobalVariable(IntType, true, GlobalValue::ExternalLinkage));

Global->setAlignment(4);

ConstantInt *TheConstant(ConstantInt::get(IntType, 2));

Constant *TheConstantExpr(
ConstantExpr::getPtrToInt(Global.get(), IntType));

ASSERT_TRUE(ConstantExpr::get( \
Instruction::And, TheConstantExpr, TheConstant)->isNullValue());
}

} // end anonymous namespace
} // end namespace llvm

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