Bug Summary

File:build/source/llvm/lib/Target/PowerPC/PPCMachineFunctionInfo.cpp
Warning:line 140, column 39
The result of the left shift is undefined due to shifting by '32', which is greater or equal to the width of type 'uint32_t'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name PPCMachineFunctionInfo.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/source/build-llvm/tools/clang/stage2-bins -resource-dir /usr/lib/llvm-17/lib/clang/17 -D _DEBUG -D _GLIBCXX_ASSERTIONS -D _GNU_SOURCE -D _LIBCPP_ENABLE_ASSERTIONS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I lib/Target/PowerPC -I /build/source/llvm/lib/Target/PowerPC -I include -I /build/source/llvm/include -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-17/lib/clang/17/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fmacro-prefix-map=/build/source/= -fcoverage-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fcoverage-prefix-map=/build/source/= -source-date-epoch 1683717183 -O2 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -Wno-misleading-indentation -std=c++17 -fdeprecated-macro -fdebug-compilation-dir=/build/source/build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/source/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/source/= -ferror-limit 19 -fvisibility=hidden -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2023-05-10-133810-16478-1 -x c++ /build/source/llvm/lib/Target/PowerPC/PPCMachineFunctionInfo.cpp
1//===-- PPCMachineFunctionInfo.cpp - Private data used for PowerPC --------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "PPCMachineFunctionInfo.h"
10#include "llvm/ADT/Twine.h"
11#include "llvm/BinaryFormat/XCOFF.h"
12#include "llvm/IR/DataLayout.h"
13#include "llvm/MC/MCContext.h"
14#include "llvm/Support/CommandLine.h"
15
16using namespace llvm;
17static cl::opt<bool> PPCDisableNonVolatileCR(
18 "ppc-disable-non-volatile-cr",
19 cl::desc("Disable the use of non-volatile CR register fields"),
20 cl::init(false), cl::Hidden);
21
22void PPCFunctionInfo::anchor() {}
23PPCFunctionInfo::PPCFunctionInfo(const Function &F,
24 const TargetSubtargetInfo *STI)
25 : DisableNonVolatileCR(PPCDisableNonVolatileCR) {}
26
27MachineFunctionInfo *
28PPCFunctionInfo::clone(BumpPtrAllocator &Allocator, MachineFunction &DestMF,
29 const DenseMap<MachineBasicBlock *, MachineBasicBlock *>
30 &Src2DstMBB) const {
31 return DestMF.cloneInfo<PPCFunctionInfo>(*this);
32}
33
34MCSymbol *PPCFunctionInfo::getPICOffsetSymbol(MachineFunction &MF) const {
35 const DataLayout &DL = MF.getDataLayout();
36 return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
37 Twine(MF.getFunctionNumber()) +
38 "$poff");
39}
40
41MCSymbol *PPCFunctionInfo::getGlobalEPSymbol(MachineFunction &MF) const {
42 const DataLayout &DL = MF.getDataLayout();
43 return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
44 "func_gep" +
45 Twine(MF.getFunctionNumber()));
46}
47
48MCSymbol *PPCFunctionInfo::getLocalEPSymbol(MachineFunction &MF) const {
49 const DataLayout &DL = MF.getDataLayout();
50 return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
51 "func_lep" +
52 Twine(MF.getFunctionNumber()));
53}
54
55MCSymbol *PPCFunctionInfo::getTOCOffsetSymbol(MachineFunction &MF) const {
56 const DataLayout &DL = MF.getDataLayout();
57 return MF.getContext().getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
58 "func_toc" +
59 Twine(MF.getFunctionNumber()));
60}
61
62bool PPCFunctionInfo::isLiveInSExt(Register VReg) const {
63 for (const std::pair<Register, ISD::ArgFlagsTy> &LiveIn : LiveInAttrs)
64 if (LiveIn.first == VReg)
65 return LiveIn.second.isSExt();
66 return false;
67}
68
69bool PPCFunctionInfo::isLiveInZExt(Register VReg) const {
70 for (const std::pair<Register, ISD::ArgFlagsTy> &LiveIn : LiveInAttrs)
71 if (LiveIn.first == VReg)
72 return LiveIn.second.isZExt();
73 return false;
74}
75
76void PPCFunctionInfo::appendParameterType(ParamType Type) {
77
78 ParamtersType.push_back(Type);
79 switch (Type) {
80 case FixedType:
81 ++FixedParmsNum;
82 return;
83 case ShortFloatingPoint:
84 case LongFloatingPoint:
85 ++FloatingParmsNum;
86 return;
87 case VectorChar:
88 case VectorShort:
89 case VectorInt:
90 case VectorFloat:
91 ++VectorParmsNum;
92 return;
93 }
94 llvm_unreachable("Error ParamType type.")::llvm::llvm_unreachable_internal("Error ParamType type.", "llvm/lib/Target/PowerPC/PPCMachineFunctionInfo.cpp"
, 94);
95}
96
97uint32_t PPCFunctionInfo::getVecExtParmsType() const {
98
99 uint32_t VectExtParamInfo = 0;
100 unsigned ShiftBits = 32 - XCOFF::TracebackTable::WidthOfParamType;
101 int Bits = 0;
102
103 if (!hasVectorParms())
1
Taking false branch
→
104 return 0;
105
106 for (const auto &Elt : ParamtersType) {
2
←
Assuming '__begin1' is equal to '__end1'
→
107 switch (Elt) {
108 case VectorChar:
109 VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
110 VectExtParamInfo |=
111 XCOFF::TracebackTable::ParmTypeIsVectorCharBit >> ShiftBits;
112 Bits += XCOFF::TracebackTable::WidthOfParamType;
113 break;
114 case VectorShort:
115 VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
116 VectExtParamInfo |=
117 XCOFF::TracebackTable::ParmTypeIsVectorShortBit >> ShiftBits;
118 Bits += XCOFF::TracebackTable::WidthOfParamType;
119 break;
120 case VectorInt:
121 VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
122 VectExtParamInfo |=
123 XCOFF::TracebackTable::ParmTypeIsVectorIntBit >> ShiftBits;
124 Bits += XCOFF::TracebackTable::WidthOfParamType;
125 break;
126 case VectorFloat:
127 VectExtParamInfo <<= XCOFF::TracebackTable::WidthOfParamType;
128 VectExtParamInfo |=
129 XCOFF::TracebackTable::ParmTypeIsVectorFloatBit >> ShiftBits;
130 Bits += XCOFF::TracebackTable::WidthOfParamType;
131 break;
132 default:
133 break;
134 }
135
136 // There are only 32bits in the VectExtParamInfo.
137 if (Bits >= 32)
138 break;
139 }
140 return Bits
2.1
'Bits' is < 32
 < 32 ? VectExtParamInfo << (32 - Bits) : VectExtParamInfo;
3
←
'?' condition is true
→
4
←
The result of the left shift is undefined due to shifting by '32', which is greater or equal to the width of type 'uint32_t'
141}
142
143uint32_t PPCFunctionInfo::getParmsType() const {
144 uint32_t ParamsTypeInfo = 0;
145 unsigned ShiftBits = 32 - XCOFF::TracebackTable::WidthOfParamType;
146
147 int Bits = 0;
148 for (const auto &Elt : ParamtersType) {
149
150 if (Bits > 31 || (Bits > 30 && (Elt != FixedType || hasVectorParms())))
151 break;
152
153 switch (Elt) {
154 case FixedType:
155 if (hasVectorParms()) {
156 //'00' ==> fixed parameter if HasVectorParms is true.
157 ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
158 ParamsTypeInfo |=
159 XCOFF::TracebackTable::ParmTypeIsFixedBits >> ShiftBits;
160 Bits += XCOFF::TracebackTable::WidthOfParamType;
161 } else {
162 //'0' ==> fixed parameter if HasVectorParms is false.
163 ParamsTypeInfo <<= 1;
164 ++Bits;
165 }
166 break;
167 case ShortFloatingPoint:
168 // '10'b => floating point short parameter.
169 ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
170 ParamsTypeInfo |=
171 XCOFF::TracebackTable::ParmTypeIsFloatingBits >> ShiftBits;
172 Bits += XCOFF::TracebackTable::WidthOfParamType;
173 break;
174 case LongFloatingPoint:
175 // '11'b => floating point long parameter.
176 ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
177 ParamsTypeInfo |=
178 XCOFF::TracebackTable::ParmTypeIsDoubleBits >> ShiftBits;
179 Bits += XCOFF::TracebackTable::WidthOfParamType;
180 break;
181 case VectorChar:
182 case VectorShort:
183 case VectorInt:
184 case VectorFloat:
185 // '01' ==> vector parameter
186 ParamsTypeInfo <<= XCOFF::TracebackTable::WidthOfParamType;
187 ParamsTypeInfo |=
188 XCOFF::TracebackTable::ParmTypeIsVectorBits >> ShiftBits;
189 Bits += XCOFF::TracebackTable::WidthOfParamType;
190 break;
191 }
192 }
193
194 return Bits < 32 ? ParamsTypeInfo << (32 - Bits) : ParamsTypeInfo;
195}