Bug Summary

File:llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp
Warning:line 676, column 17
Forming reference to null pointer

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name HexagonAsmBackend.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -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 -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/lib/Target/Hexagon/MCTargetDesc -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/lib/Target/Hexagon/MCTargetDesc -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/lib/Target/Hexagon/MCTargetDesc -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/lib/Target/Hexagon -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/lib/Target/Hexagon -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/include -I /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/include -D 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-14/lib/clang/14.0.0/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 -O2 -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 -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/build-llvm/lib/Target/Hexagon/MCTargetDesc -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e=. -ferror-limit 19 -fvisibility hidden -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -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-2021-09-04-040900-46481-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210903100615+fd66b44ec19e/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp
1//===-- HexagonAsmBackend.cpp - Hexagon Assembler Backend -----------------===//
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 "HexagonFixupKinds.h"
10#include "MCTargetDesc/HexagonBaseInfo.h"
11#include "MCTargetDesc/HexagonMCChecker.h"
12#include "MCTargetDesc/HexagonMCCodeEmitter.h"
13#include "MCTargetDesc/HexagonMCInstrInfo.h"
14#include "MCTargetDesc/HexagonMCShuffler.h"
15#include "MCTargetDesc/HexagonMCTargetDesc.h"
16#include "llvm/MC/MCAsmBackend.h"
17#include "llvm/MC/MCAsmLayout.h"
18#include "llvm/MC/MCAssembler.h"
19#include "llvm/MC/MCContext.h"
20#include "llvm/MC/MCELFObjectWriter.h"
21#include "llvm/MC/MCFixupKindInfo.h"
22#include "llvm/MC/MCInstrInfo.h"
23#include "llvm/MC/MCObjectWriter.h"
24#include "llvm/Support/Debug.h"
25#include "llvm/Support/EndianStream.h"
26#include "llvm/Support/TargetRegistry.h"
27
28#include <sstream>
29
30using namespace llvm;
31using namespace Hexagon;
32
33#define DEBUG_TYPE"hexagon-asm-backend" "hexagon-asm-backend"
34
35static cl::opt<bool> DisableFixup
36 ("mno-fixup", cl::desc("Disable fixing up resolved relocations for Hexagon"));
37
38namespace {
39
40class HexagonAsmBackend : public MCAsmBackend {
41 uint8_t OSABI;
42 StringRef CPU;
43 mutable uint64_t relaxedCnt;
44 std::unique_ptr <MCInstrInfo> MCII;
45 std::unique_ptr <MCInst *> RelaxTarget;
46 MCInst * Extender;
47 unsigned MaxPacketSize;
48
49 void ReplaceInstruction(MCCodeEmitter &E, MCRelaxableFragment &RF,
50 MCInst &HMB) const {
51 SmallVector<MCFixup, 4> Fixups;
52 SmallString<256> Code;
53 raw_svector_ostream VecOS(Code);
54 E.encodeInstruction(HMB, VecOS, Fixups, *RF.getSubtargetInfo());
55
56 // Update the fragment.
57 RF.setInst(HMB);
58 RF.getContents() = Code;
59 RF.getFixups() = Fixups;
60 }
61
62public:
63 HexagonAsmBackend(const Target &T, const Triple &TT, uint8_t OSABI,
64 StringRef CPU)
65 : MCAsmBackend(support::little), OSABI(OSABI), CPU(CPU), relaxedCnt(0),
66 MCII(T.createMCInstrInfo()), RelaxTarget(new MCInst *),
67 Extender(nullptr), MaxPacketSize(HexagonMCInstrInfo::packetSize(CPU))
68 {}
69
70 std::unique_ptr<MCObjectTargetWriter>
71 createObjectTargetWriter() const override {
72 return createHexagonELFObjectWriter(OSABI, CPU);
73 }
74
75 void setExtender(MCContext &Context) const {
76 if (Extender == nullptr)
77 const_cast<HexagonAsmBackend *>(this)->Extender = Context.createMCInst();
78 }
79
80 MCInst *takeExtender() const {
81 assert(Extender != nullptr)(static_cast<void> (0));
82 MCInst * Result = Extender;
83 const_cast<HexagonAsmBackend *>(this)->Extender = nullptr;
84 return Result;
85 }
86
87 unsigned getNumFixupKinds() const override {
88 return Hexagon::NumTargetFixupKinds;
89 }
90
91 const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override {
92 const static MCFixupKindInfo Infos[Hexagon::NumTargetFixupKinds] = {
93 // This table *must* be in same the order of fixup_* kinds in
94 // HexagonFixupKinds.h.
95 //
96 // namei offset bits flags
97 { "fixup_Hexagon_B22_PCREL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
98 { "fixup_Hexagon_B15_PCREL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
99 { "fixup_Hexagon_B7_PCREL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
100 { "fixup_Hexagon_LO16", 0, 32, 0 },
101 { "fixup_Hexagon_HI16", 0, 32, 0 },
102 { "fixup_Hexagon_32", 0, 32, 0 },
103 { "fixup_Hexagon_16", 0, 32, 0 },
104 { "fixup_Hexagon_8", 0, 32, 0 },
105 { "fixup_Hexagon_GPREL16_0", 0, 32, 0 },
106 { "fixup_Hexagon_GPREL16_1", 0, 32, 0 },
107 { "fixup_Hexagon_GPREL16_2", 0, 32, 0 },
108 { "fixup_Hexagon_GPREL16_3", 0, 32, 0 },
109 { "fixup_Hexagon_HL16", 0, 32, 0 },
110 { "fixup_Hexagon_B13_PCREL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
111 { "fixup_Hexagon_B9_PCREL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
112 { "fixup_Hexagon_B32_PCREL_X", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
113 { "fixup_Hexagon_32_6_X", 0, 32, 0 },
114 { "fixup_Hexagon_B22_PCREL_X", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
115 { "fixup_Hexagon_B15_PCREL_X", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
116 { "fixup_Hexagon_B13_PCREL_X", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
117 { "fixup_Hexagon_B9_PCREL_X", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
118 { "fixup_Hexagon_B7_PCREL_X", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
119 { "fixup_Hexagon_16_X", 0, 32, 0 },
120 { "fixup_Hexagon_12_X", 0, 32, 0 },
121 { "fixup_Hexagon_11_X", 0, 32, 0 },
122 { "fixup_Hexagon_10_X", 0, 32, 0 },
123 { "fixup_Hexagon_9_X", 0, 32, 0 },
124 { "fixup_Hexagon_8_X", 0, 32, 0 },
125 { "fixup_Hexagon_7_X", 0, 32, 0 },
126 { "fixup_Hexagon_6_X", 0, 32, 0 },
127 { "fixup_Hexagon_32_PCREL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
128 { "fixup_Hexagon_COPY", 0, 32, 0 },
129 { "fixup_Hexagon_GLOB_DAT", 0, 32, 0 },
130 { "fixup_Hexagon_JMP_SLOT", 0, 32, 0 },
131 { "fixup_Hexagon_RELATIVE", 0, 32, 0 },
132 { "fixup_Hexagon_PLT_B22_PCREL", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
133 { "fixup_Hexagon_GOTREL_LO16", 0, 32, 0 },
134 { "fixup_Hexagon_GOTREL_HI16", 0, 32, 0 },
135 { "fixup_Hexagon_GOTREL_32", 0, 32, 0 },
136 { "fixup_Hexagon_GOT_LO16", 0, 32, 0 },
137 { "fixup_Hexagon_GOT_HI16", 0, 32, 0 },
138 { "fixup_Hexagon_GOT_32", 0, 32, 0 },
139 { "fixup_Hexagon_GOT_16", 0, 32, 0 },
140 { "fixup_Hexagon_DTPMOD_32", 0, 32, 0 },
141 { "fixup_Hexagon_DTPREL_LO16", 0, 32, 0 },
142 { "fixup_Hexagon_DTPREL_HI16", 0, 32, 0 },
143 { "fixup_Hexagon_DTPREL_32", 0, 32, 0 },
144 { "fixup_Hexagon_DTPREL_16", 0, 32, 0 },
145 { "fixup_Hexagon_GD_PLT_B22_PCREL",0, 32, MCFixupKindInfo::FKF_IsPCRel },
146 { "fixup_Hexagon_LD_PLT_B22_PCREL",0, 32, MCFixupKindInfo::FKF_IsPCRel },
147 { "fixup_Hexagon_GD_GOT_LO16", 0, 32, 0 },
148 { "fixup_Hexagon_GD_GOT_HI16", 0, 32, 0 },
149 { "fixup_Hexagon_GD_GOT_32", 0, 32, 0 },
150 { "fixup_Hexagon_GD_GOT_16", 0, 32, 0 },
151 { "fixup_Hexagon_LD_GOT_LO16", 0, 32, 0 },
152 { "fixup_Hexagon_LD_GOT_HI16", 0, 32, 0 },
153 { "fixup_Hexagon_LD_GOT_32", 0, 32, 0 },
154 { "fixup_Hexagon_LD_GOT_16", 0, 32, 0 },
155 { "fixup_Hexagon_IE_LO16", 0, 32, 0 },
156 { "fixup_Hexagon_IE_HI16", 0, 32, 0 },
157 { "fixup_Hexagon_IE_32", 0, 32, 0 },
158 { "fixup_Hexagon_IE_16", 0, 32, 0 },
159 { "fixup_Hexagon_IE_GOT_LO16", 0, 32, 0 },
160 { "fixup_Hexagon_IE_GOT_HI16", 0, 32, 0 },
161 { "fixup_Hexagon_IE_GOT_32", 0, 32, 0 },
162 { "fixup_Hexagon_IE_GOT_16", 0, 32, 0 },
163 { "fixup_Hexagon_TPREL_LO16", 0, 32, 0 },
164 { "fixup_Hexagon_TPREL_HI16", 0, 32, 0 },
165 { "fixup_Hexagon_TPREL_32", 0, 32, 0 },
166 { "fixup_Hexagon_TPREL_16", 0, 32, 0 },
167 { "fixup_Hexagon_6_PCREL_X", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
168 { "fixup_Hexagon_GOTREL_32_6_X", 0, 32, 0 },
169 { "fixup_Hexagon_GOTREL_16_X", 0, 32, 0 },
170 { "fixup_Hexagon_GOTREL_11_X", 0, 32, 0 },
171 { "fixup_Hexagon_GOT_32_6_X", 0, 32, 0 },
172 { "fixup_Hexagon_GOT_16_X", 0, 32, 0 },
173 { "fixup_Hexagon_GOT_11_X", 0, 32, 0 },
174 { "fixup_Hexagon_DTPREL_32_6_X", 0, 32, 0 },
175 { "fixup_Hexagon_DTPREL_16_X", 0, 32, 0 },
176 { "fixup_Hexagon_DTPREL_11_X", 0, 32, 0 },
177 { "fixup_Hexagon_GD_GOT_32_6_X", 0, 32, 0 },
178 { "fixup_Hexagon_GD_GOT_16_X", 0, 32, 0 },
179 { "fixup_Hexagon_GD_GOT_11_X", 0, 32, 0 },
180 { "fixup_Hexagon_LD_GOT_32_6_X", 0, 32, 0 },
181 { "fixup_Hexagon_LD_GOT_16_X", 0, 32, 0 },
182 { "fixup_Hexagon_LD_GOT_11_X", 0, 32, 0 },
183 { "fixup_Hexagon_IE_32_6_X", 0, 32, 0 },
184 { "fixup_Hexagon_IE_16_X", 0, 32, 0 },
185 { "fixup_Hexagon_IE_GOT_32_6_X", 0, 32, 0 },
186 { "fixup_Hexagon_IE_GOT_16_X", 0, 32, 0 },
187 { "fixup_Hexagon_IE_GOT_11_X", 0, 32, 0 },
188 { "fixup_Hexagon_TPREL_32_6_X", 0, 32, 0 },
189 { "fixup_Hexagon_TPREL_16_X", 0, 32, 0 },
190 { "fixup_Hexagon_TPREL_11_X", 0, 32, 0 },
191 { "fixup_Hexagon_GD_PLT_B22_PCREL_X",0, 32, MCFixupKindInfo::FKF_IsPCRel },
192 { "fixup_Hexagon_GD_PLT_B32_PCREL_X",0, 32, MCFixupKindInfo::FKF_IsPCRel },
193 { "fixup_Hexagon_LD_PLT_B22_PCREL_X",0, 32, MCFixupKindInfo::FKF_IsPCRel },
194 { "fixup_Hexagon_LD_PLT_B32_PCREL_X",0, 32, MCFixupKindInfo::FKF_IsPCRel }
195 };
196
197 if (Kind < FirstTargetFixupKind)
198 return MCAsmBackend::getFixupKindInfo(Kind);
199
200 assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&(static_cast<void> (0))
201 "Invalid kind!")(static_cast<void> (0));
202 return Infos[Kind - FirstTargetFixupKind];
203 }
204
205 bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
206 const MCValue &Target) override {
207 switch(Fixup.getTargetKind()) {
208 default:
209 llvm_unreachable("Unknown Fixup Kind!")__builtin_unreachable();
210
211 case fixup_Hexagon_LO16:
212 case fixup_Hexagon_HI16:
213 case fixup_Hexagon_16:
214 case fixup_Hexagon_8:
215 case fixup_Hexagon_GPREL16_0:
216 case fixup_Hexagon_GPREL16_1:
217 case fixup_Hexagon_GPREL16_2:
218 case fixup_Hexagon_GPREL16_3:
219 case fixup_Hexagon_HL16:
220 case fixup_Hexagon_32_6_X:
221 case fixup_Hexagon_16_X:
222 case fixup_Hexagon_12_X:
223 case fixup_Hexagon_11_X:
224 case fixup_Hexagon_10_X:
225 case fixup_Hexagon_9_X:
226 case fixup_Hexagon_8_X:
227 case fixup_Hexagon_7_X:
228 case fixup_Hexagon_6_X:
229 case fixup_Hexagon_COPY:
230 case fixup_Hexagon_GLOB_DAT:
231 case fixup_Hexagon_JMP_SLOT:
232 case fixup_Hexagon_RELATIVE:
233 case fixup_Hexagon_PLT_B22_PCREL:
234 case fixup_Hexagon_GOTREL_LO16:
235 case fixup_Hexagon_GOTREL_HI16:
236 case fixup_Hexagon_GOTREL_32:
237 case fixup_Hexagon_GOT_LO16:
238 case fixup_Hexagon_GOT_HI16:
239 case fixup_Hexagon_GOT_32:
240 case fixup_Hexagon_GOT_16:
241 case fixup_Hexagon_DTPMOD_32:
242 case fixup_Hexagon_DTPREL_LO16:
243 case fixup_Hexagon_DTPREL_HI16:
244 case fixup_Hexagon_DTPREL_32:
245 case fixup_Hexagon_DTPREL_16:
246 case fixup_Hexagon_GD_PLT_B22_PCREL:
247 case fixup_Hexagon_LD_PLT_B22_PCREL:
248 case fixup_Hexagon_GD_GOT_LO16:
249 case fixup_Hexagon_GD_GOT_HI16:
250 case fixup_Hexagon_GD_GOT_32:
251 case fixup_Hexagon_GD_GOT_16:
252 case fixup_Hexagon_LD_GOT_LO16:
253 case fixup_Hexagon_LD_GOT_HI16:
254 case fixup_Hexagon_LD_GOT_32:
255 case fixup_Hexagon_LD_GOT_16:
256 case fixup_Hexagon_IE_LO16:
257 case fixup_Hexagon_IE_HI16:
258 case fixup_Hexagon_IE_32:
259 case fixup_Hexagon_IE_16:
260 case fixup_Hexagon_IE_GOT_LO16:
261 case fixup_Hexagon_IE_GOT_HI16:
262 case fixup_Hexagon_IE_GOT_32:
263 case fixup_Hexagon_IE_GOT_16:
264 case fixup_Hexagon_TPREL_LO16:
265 case fixup_Hexagon_TPREL_HI16:
266 case fixup_Hexagon_TPREL_32:
267 case fixup_Hexagon_TPREL_16:
268 case fixup_Hexagon_GOTREL_32_6_X:
269 case fixup_Hexagon_GOTREL_16_X:
270 case fixup_Hexagon_GOTREL_11_X:
271 case fixup_Hexagon_GOT_32_6_X:
272 case fixup_Hexagon_GOT_16_X:
273 case fixup_Hexagon_GOT_11_X:
274 case fixup_Hexagon_DTPREL_32_6_X:
275 case fixup_Hexagon_DTPREL_16_X:
276 case fixup_Hexagon_DTPREL_11_X:
277 case fixup_Hexagon_GD_GOT_32_6_X:
278 case fixup_Hexagon_GD_GOT_16_X:
279 case fixup_Hexagon_GD_GOT_11_X:
280 case fixup_Hexagon_LD_GOT_32_6_X:
281 case fixup_Hexagon_LD_GOT_16_X:
282 case fixup_Hexagon_LD_GOT_11_X:
283 case fixup_Hexagon_IE_32_6_X:
284 case fixup_Hexagon_IE_16_X:
285 case fixup_Hexagon_IE_GOT_32_6_X:
286 case fixup_Hexagon_IE_GOT_16_X:
287 case fixup_Hexagon_IE_GOT_11_X:
288 case fixup_Hexagon_TPREL_32_6_X:
289 case fixup_Hexagon_TPREL_16_X:
290 case fixup_Hexagon_TPREL_11_X:
291 case fixup_Hexagon_32_PCREL:
292 case fixup_Hexagon_6_PCREL_X:
293 case fixup_Hexagon_23_REG:
294 case fixup_Hexagon_27_REG:
295 case fixup_Hexagon_GD_PLT_B22_PCREL_X:
296 case fixup_Hexagon_GD_PLT_B32_PCREL_X:
297 case fixup_Hexagon_LD_PLT_B22_PCREL_X:
298 case fixup_Hexagon_LD_PLT_B32_PCREL_X:
299 // These relocations should always have a relocation recorded
300 return true;
301
302 case fixup_Hexagon_B22_PCREL:
303 //IsResolved = false;
304 break;
305
306 case fixup_Hexagon_B13_PCREL:
307 case fixup_Hexagon_B13_PCREL_X:
308 case fixup_Hexagon_B32_PCREL_X:
309 case fixup_Hexagon_B22_PCREL_X:
310 case fixup_Hexagon_B15_PCREL:
311 case fixup_Hexagon_B15_PCREL_X:
312 case fixup_Hexagon_B9_PCREL:
313 case fixup_Hexagon_B9_PCREL_X:
314 case fixup_Hexagon_B7_PCREL:
315 case fixup_Hexagon_B7_PCREL_X:
316 if (DisableFixup)
317 return true;
318 break;
319
320 case FK_Data_1:
321 case FK_Data_2:
322 case FK_Data_4:
323 case FK_PCRel_4:
324 case fixup_Hexagon_32:
325 // Leave these relocations alone as they are used for EH.
326 return false;
327 }
328 return false;
329 }
330
331 /// getFixupKindNumBytes - The number of bytes the fixup may change.
332 static unsigned getFixupKindNumBytes(unsigned Kind) {
333 switch (Kind) {
334 default:
335 return 0;
336
337 case FK_Data_1:
338 return 1;
339 case FK_Data_2:
340 return 2;
341 case FK_Data_4: // this later gets mapped to R_HEX_32
342 case FK_PCRel_4: // this later gets mapped to R_HEX_32_PCREL
343 case fixup_Hexagon_32:
344 case fixup_Hexagon_B32_PCREL_X:
345 case fixup_Hexagon_B22_PCREL:
346 case fixup_Hexagon_B22_PCREL_X:
347 case fixup_Hexagon_B15_PCREL:
348 case fixup_Hexagon_B15_PCREL_X:
349 case fixup_Hexagon_B13_PCREL:
350 case fixup_Hexagon_B13_PCREL_X:
351 case fixup_Hexagon_B9_PCREL:
352 case fixup_Hexagon_B9_PCREL_X:
353 case fixup_Hexagon_B7_PCREL:
354 case fixup_Hexagon_B7_PCREL_X:
355 case fixup_Hexagon_GD_PLT_B32_PCREL_X:
356 case fixup_Hexagon_LD_PLT_B32_PCREL_X:
357 return 4;
358 }
359 }
360
361 // Make up for left shift when encoding the operand.
362 static uint64_t adjustFixupValue(MCFixupKind Kind, uint64_t Value) {
363 switch((unsigned)Kind) {
364 default:
365 break;
366
367 case fixup_Hexagon_B7_PCREL:
368 case fixup_Hexagon_B9_PCREL:
369 case fixup_Hexagon_B13_PCREL:
370 case fixup_Hexagon_B15_PCREL:
371 case fixup_Hexagon_B22_PCREL:
372 Value >>= 2;
373 break;
374
375 case fixup_Hexagon_B7_PCREL_X:
376 case fixup_Hexagon_B9_PCREL_X:
377 case fixup_Hexagon_B13_PCREL_X:
378 case fixup_Hexagon_B15_PCREL_X:
379 case fixup_Hexagon_B22_PCREL_X:
380 Value &= 0x3f;
381 break;
382
383 case fixup_Hexagon_B32_PCREL_X:
384 case fixup_Hexagon_GD_PLT_B32_PCREL_X:
385 case fixup_Hexagon_LD_PLT_B32_PCREL_X:
386 Value >>= 6;
387 break;
388 }
389 return (Value);
390 }
391
392 void HandleFixupError(const int bits, const int align_bits,
393 const int64_t FixupValue, const char *fixupStr) const {
394 // Error: value 1124 out of range: -1024-1023 when resolving
395 // symbol in file xprtsock.S
396 const APInt IntMin = APInt::getSignedMinValue(bits+align_bits);
397 const APInt IntMax = APInt::getSignedMaxValue(bits+align_bits);
398 std::stringstream errStr;
399 errStr << "\nError: value " <<
400 FixupValue <<
401 " out of range: " <<
402 IntMin.getSExtValue() <<
403 "-" <<
404 IntMax.getSExtValue() <<
405 " when resolving " <<
406 fixupStr <<
407 " fixup\n";
408 llvm_unreachable(errStr.str().c_str())__builtin_unreachable();
409 }
410
411 /// ApplyFixup - Apply the \arg Value for given \arg Fixup into the provided
412 /// data fragment, at the offset specified by the fixup and following the
413 /// fixup kind as appropriate.
414 void applyFixup(const MCAssembler &Asm, const MCFixup &Fixup,
415 const MCValue &Target, MutableArrayRef<char> Data,
416 uint64_t FixupValue, bool IsResolved,
417 const MCSubtargetInfo *STI) const override {
418
419 // When FixupValue is 0 the relocation is external and there
420 // is nothing for us to do.
421 if (!FixupValue) return;
422
423 MCFixupKind Kind = Fixup.getKind();
424 uint64_t Value;
425 uint32_t InstMask;
426 uint32_t Reloc;
427
428 // LLVM gives us an encoded value, we have to convert it back
429 // to a real offset before we can use it.
430 uint32_t Offset = Fixup.getOffset();
431 unsigned NumBytes = getFixupKindNumBytes(Kind);
432 assert(Offset + NumBytes <= Data.size() && "Invalid fixup offset!")(static_cast<void> (0));
433 char *InstAddr = Data.data() + Offset;
434
435 Value = adjustFixupValue(Kind, FixupValue);
436 if(!Value)
437 return;
438 int sValue = (int)Value;
439
440 switch((unsigned)Kind) {
441 default:
442 return;
443
444 case fixup_Hexagon_B7_PCREL:
445 if (!(isIntN(7, sValue)))
446 HandleFixupError(7, 2, (int64_t)FixupValue, "B7_PCREL");
447 LLVM_FALLTHROUGH[[gnu::fallthrough]];
448 case fixup_Hexagon_B7_PCREL_X:
449 InstMask = 0x00001f18; // Word32_B7
450 Reloc = (((Value >> 2) & 0x1f) << 8) | // Value 6-2 = Target 12-8
451 ((Value & 0x3) << 3); // Value 1-0 = Target 4-3
452 break;
453
454 case fixup_Hexagon_B9_PCREL:
455 if (!(isIntN(9, sValue)))
456 HandleFixupError(9, 2, (int64_t)FixupValue, "B9_PCREL");
457 LLVM_FALLTHROUGH[[gnu::fallthrough]];
458 case fixup_Hexagon_B9_PCREL_X:
459 InstMask = 0x003000fe; // Word32_B9
460 Reloc = (((Value >> 7) & 0x3) << 20) | // Value 8-7 = Target 21-20
461 ((Value & 0x7f) << 1); // Value 6-0 = Target 7-1
462 break;
463
464 // Since the existing branches that use this relocation cannot be
465 // extended, they should only be fixed up if the target is within range.
466 case fixup_Hexagon_B13_PCREL:
467 if (!(isIntN(13, sValue)))
468 HandleFixupError(13, 2, (int64_t)FixupValue, "B13_PCREL");
469 LLVM_FALLTHROUGH[[gnu::fallthrough]];
470 case fixup_Hexagon_B13_PCREL_X:
471 InstMask = 0x00202ffe; // Word32_B13
472 Reloc = (((Value >> 12) & 0x1) << 21) | // Value 12 = Target 21
473 (((Value >> 11) & 0x1) << 13) | // Value 11 = Target 13
474 ((Value & 0x7ff) << 1); // Value 10-0 = Target 11-1
475 break;
476
477 case fixup_Hexagon_B15_PCREL:
478 if (!(isIntN(15, sValue)))
479 HandleFixupError(15, 2, (int64_t)FixupValue, "B15_PCREL");
480 LLVM_FALLTHROUGH[[gnu::fallthrough]];
481 case fixup_Hexagon_B15_PCREL_X:
482 InstMask = 0x00df20fe; // Word32_B15
483 Reloc = (((Value >> 13) & 0x3) << 22) | // Value 14-13 = Target 23-22
484 (((Value >> 8) & 0x1f) << 16) | // Value 12-8 = Target 20-16
485 (((Value >> 7) & 0x1) << 13) | // Value 7 = Target 13
486 ((Value & 0x7f) << 1); // Value 6-0 = Target 7-1
487 break;
488
489 case fixup_Hexagon_B22_PCREL:
490 if (!(isIntN(22, sValue)))
491 HandleFixupError(22, 2, (int64_t)FixupValue, "B22_PCREL");
492 LLVM_FALLTHROUGH[[gnu::fallthrough]];
493 case fixup_Hexagon_B22_PCREL_X:
494 InstMask = 0x01ff3ffe; // Word32_B22
495 Reloc = (((Value >> 13) & 0x1ff) << 16) | // Value 21-13 = Target 24-16
496 ((Value & 0x1fff) << 1); // Value 12-0 = Target 13-1
497 break;
498
499 case fixup_Hexagon_B32_PCREL_X:
500 InstMask = 0x0fff3fff; // Word32_X26
501 Reloc = (((Value >> 14) & 0xfff) << 16) | // Value 25-14 = Target 27-16
502 (Value & 0x3fff); // Value 13-0 = Target 13-0
503 break;
504
505 case FK_Data_1:
506 case FK_Data_2:
507 case FK_Data_4:
508 case fixup_Hexagon_32:
509 InstMask = 0xffffffff; // Word32
510 Reloc = Value;
511 break;
512 }
513
514 LLVM_DEBUG(dbgs() << "Name=" << getFixupKindInfo(Kind).Name << "("do { } while (false)
515 << (unsigned)Kind << ")\n")do { } while (false);
516 LLVM_DEBUG(do { } while (false)
517 uint32_t OldData = 0; for (unsigned i = 0; i < NumBytes; i++) OldData |=do { } while (false)
518 (InstAddr[i] << (i * 8)) & (0xff << (i * 8));do { } while (false)
519 dbgs() << "\tBValue=0x"; dbgs().write_hex(Value) << ": AValue=0x";do { } while (false)
520 dbgs().write_hex(FixupValue)do { } while (false)
521 << ": Offset=" << Offset << ": Size=" << Data.size() << ": OInst=0x";do { } while (false)
522 dbgs().write_hex(OldData) << ": Reloc=0x"; dbgs().write_hex(Reloc);)do { } while (false);
523
524 // For each byte of the fragment that the fixup touches, mask in the
525 // bits from the fixup value. The Value has been "split up" into the
526 // appropriate bitfields above.
527 for (unsigned i = 0; i < NumBytes; i++){
528 InstAddr[i] &= uint8_t(~InstMask >> (i * 8)) & 0xff; // Clear reloc bits
529 InstAddr[i] |= uint8_t(Reloc >> (i * 8)) & 0xff; // Apply new reloc
530 }
531
532 LLVM_DEBUG(uint32_t NewData = 0;do { } while (false)
533 for (unsigned i = 0; i < NumBytes; i++) NewData |=do { } while (false)
534 (InstAddr[i] << (i * 8)) & (0xff << (i * 8));do { } while (false)
535 dbgs() << ": NInst=0x"; dbgs().write_hex(NewData) << "\n";)do { } while (false);
536 }
537
538 bool isInstRelaxable(MCInst const &HMI) const {
539 const MCInstrDesc &MCID = HexagonMCInstrInfo::getDesc(*MCII, HMI);
540 bool Relaxable = false;
541 // Branches and loop-setup insns are handled as necessary by relaxation.
542 if (llvm::HexagonMCInstrInfo::getType(*MCII, HMI) == HexagonII::TypeJ ||
543 (llvm::HexagonMCInstrInfo::getType(*MCII, HMI) == HexagonII::TypeCJ &&
544 MCID.isBranch()) ||
545 (llvm::HexagonMCInstrInfo::getType(*MCII, HMI) == HexagonII::TypeNCJ &&
546 MCID.isBranch()) ||
547 (llvm::HexagonMCInstrInfo::getType(*MCII, HMI) == HexagonII::TypeCR &&
548 HMI.getOpcode() != Hexagon::C4_addipc))
549 if (HexagonMCInstrInfo::isExtendable(*MCII, HMI)) {
550 Relaxable = true;
551 MCOperand const &Operand =
552 HMI.getOperand(HexagonMCInstrInfo::getExtendableOp(*MCII, HMI));
553 if (HexagonMCInstrInfo::mustNotExtend(*Operand.getExpr()))
554 Relaxable = false;
555 }
556
557 return Relaxable;
558 }
559
560 /// MayNeedRelaxation - Check whether the given instruction may need
561 /// relaxation.
562 ///
563 /// \param Inst - The instruction to test.
564 bool mayNeedRelaxation(MCInst const &Inst,
565 const MCSubtargetInfo &STI) const override {
566 return true;
567 }
568
569 /// fixupNeedsRelaxation - Target specific predicate for whether a given
570 /// fixup requires the associated instruction to be relaxed.
571 bool fixupNeedsRelaxationAdvanced(const MCFixup &Fixup, bool Resolved,
572 uint64_t Value,
573 const MCRelaxableFragment *DF,
574 const MCAsmLayout &Layout,
575 const bool WasForced) const override {
576 MCInst const &MCB = DF->getInst();
577 assert(HexagonMCInstrInfo::isBundle(MCB))(static_cast<void> (0));
578
579 *RelaxTarget = nullptr;
580 MCInst &MCI = const_cast<MCInst &>(HexagonMCInstrInfo::instruction(
581 MCB, Fixup.getOffset() / HEXAGON_INSTR_SIZE4));
582 bool Relaxable = isInstRelaxable(MCI);
583 if (Relaxable == false)
584 return false;
585 // If we cannot resolve the fixup value, it requires relaxation.
586 if (!Resolved) {
587 switch (Fixup.getTargetKind()) {
588 case fixup_Hexagon_B22_PCREL:
589 // GetFixupCount assumes B22 won't relax
590 LLVM_FALLTHROUGH[[gnu::fallthrough]];
591 default:
592 return false;
593 break;
594 case fixup_Hexagon_B13_PCREL:
595 case fixup_Hexagon_B15_PCREL:
596 case fixup_Hexagon_B9_PCREL:
597 case fixup_Hexagon_B7_PCREL: {
598 if (HexagonMCInstrInfo::bundleSize(MCB) < HEXAGON_PACKET_SIZE4) {
599 ++relaxedCnt;
600 *RelaxTarget = &MCI;
601 setExtender(Layout.getAssembler().getContext());
602 return true;
603 } else {
604 return false;
605 }
606 break;
607 }
608 }
609 }
610
611 MCFixupKind Kind = Fixup.getKind();
612 int64_t sValue = Value;
613 int64_t maxValue;
614
615 switch ((unsigned)Kind) {
616 case fixup_Hexagon_B7_PCREL:
617 maxValue = 1 << 8;
618 break;
619 case fixup_Hexagon_B9_PCREL:
620 maxValue = 1 << 10;
621 break;
622 case fixup_Hexagon_B15_PCREL:
623 maxValue = 1 << 16;
624 break;
625 case fixup_Hexagon_B22_PCREL:
626 maxValue = 1 << 23;
627 break;
628 default:
629 maxValue = INT64_MAX(9223372036854775807L);
630 break;
631 }
632
633 bool isFarAway = -maxValue > sValue || sValue > maxValue - 1;
634
635 if (isFarAway) {
636 if (HexagonMCInstrInfo::bundleSize(MCB) < HEXAGON_PACKET_SIZE4) {
637 ++relaxedCnt;
638 *RelaxTarget = &MCI;
639 setExtender(Layout.getAssembler().getContext());
640 return true;
641 }
642 }
643
644 return false;
645 }
646
647 /// Simple predicate for targets where !Resolved implies requiring relaxation
648 bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
649 const MCRelaxableFragment *DF,
650 const MCAsmLayout &Layout) const override {
651 llvm_unreachable("Handled by fixupNeedsRelaxationAdvanced")__builtin_unreachable();
652 }
653
654 void relaxInstruction(MCInst &Inst,
655 const MCSubtargetInfo &STI) const override {
656 assert(HexagonMCInstrInfo::isBundle(Inst) &&(static_cast<void> (0))
657 "Hexagon relaxInstruction only works on bundles")(static_cast<void> (0));
658
659 MCInst Res;
660 Res.setOpcode(Hexagon::BUNDLE);
661 Res.addOperand(MCOperand::createImm(Inst.getOperand(0).getImm()));
662 // Copy the results into the bundle.
663 bool Update = false;
664 for (auto &I : HexagonMCInstrInfo::bundleInstructions(Inst)) {
1
Assuming '__begin2' is not equal to '__end2'
→
665 MCInst &CrntHMI = const_cast<MCInst &>(*I.getInst());
4
←
'CrntHMI' initialized here
→
666
667 // if immediate extender needed, add it in
668 if (*RelaxTarget == &CrntHMI) {
2
←
Assuming the condition is true
→
3
←
Taking true branch
→
5
←
Assuming pointer value is null
→
6
←
Taking true branch
→
669 Update = true;
670 assert((HexagonMCInstrInfo::bundleSize(Res) < HEXAGON_PACKET_SIZE) &&(static_cast<void> (0))
671 "No room to insert extender for relaxation")(static_cast<void> (0));
672
673 MCInst *HMIx = takeExtender();
674 *HMIx = HexagonMCInstrInfo::deriveExtender(
675 *MCII, CrntHMI,
676 HexagonMCInstrInfo::getExtendableOperand(*MCII, CrntHMI));
7
←
Forming reference to null pointer
677 Res.addOperand(MCOperand::createInst(HMIx));
678 *RelaxTarget = nullptr;
679 }
680 // now copy over the original instruction(the one we may have extended)
681 Res.addOperand(MCOperand::createInst(I.getInst()));
682 }
683
684 Inst = std::move(Res);
685 (void)Update;
686 assert(Update && "Didn't find relaxation target")(static_cast<void> (0));
687 }
688
689 bool writeNopData(raw_ostream &OS, uint64_t Count) const override {
690 static const uint32_t Nopcode = 0x7f000000, // Hard-coded NOP.
691 ParseIn = 0x00004000, // In packet parse-bits.
692 ParseEnd = 0x0000c000; // End of packet parse-bits.
693
694 while (Count % HEXAGON_INSTR_SIZE4) {
695 LLVM_DEBUG(dbgs() << "Alignment not a multiple of the instruction size:"do { } while (false)
696 << Count % HEXAGON_INSTR_SIZE << "/"do { } while (false)
697 << HEXAGON_INSTR_SIZE << "\n")do { } while (false);
698 --Count;
699 OS << '\0';
700 }
701
702 while (Count) {
703 Count -= HEXAGON_INSTR_SIZE4;
704 // Close the packet whenever a multiple of the maximum packet size remains
705 uint32_t ParseBits = (Count % (MaxPacketSize * HEXAGON_INSTR_SIZE4)) ?
706 ParseIn : ParseEnd;
707 support::endian::write<uint32_t>(OS, Nopcode | ParseBits, Endian);
708 }
709 return true;
710 }
711
712 void finishLayout(MCAssembler const &Asm,
713 MCAsmLayout &Layout) const override {
714 for (auto I : Layout.getSectionOrder()) {
715 auto &Fragments = I->getFragmentList();
716 for (auto &J : Fragments) {
717 switch (J.getKind()) {
718 default:
719 break;
720 case MCFragment::FT_Align: {
721 auto Size = Asm.computeFragmentSize(Layout, J);
722 for (auto K = J.getIterator();
723 K != Fragments.begin() && Size >= HEXAGON_PACKET_SIZE4;) {
724 --K;
725 switch (K->getKind()) {
726 default:
727 break;
728 case MCFragment::FT_Align: {
729 // Don't pad before other alignments
730 Size = 0;
731 break;
732 }
733 case MCFragment::FT_Relaxable: {
734 MCContext &Context = Asm.getContext();
735 auto &RF = cast<MCRelaxableFragment>(*K);
736 auto &Inst = const_cast<MCInst &>(RF.getInst());
737 while (Size > 0 &&
738 HexagonMCInstrInfo::bundleSize(Inst) < MaxPacketSize) {
739 MCInst *Nop = Context.createMCInst();
740 Nop->setOpcode(Hexagon::A2_nop);
741 Inst.addOperand(MCOperand::createInst(Nop));
742 Size -= 4;
743 if (!HexagonMCChecker(
744 Context, *MCII, *RF.getSubtargetInfo(), Inst,
745 *Context.getRegisterInfo(), false)
746 .check()) {
747 Inst.erase(Inst.end() - 1);
748 Size = 0;
749 }
750 }
751 bool Error = HexagonMCShuffle(Context, true, *MCII,
752 *RF.getSubtargetInfo(), Inst);
753 //assert(!Error);
754 (void)Error;
755 ReplaceInstruction(Asm.getEmitter(), RF, Inst);
756 Layout.invalidateFragmentsFrom(&RF);
757 Size = 0; // Only look back one instruction
758 break;
759 }
760 }
761 }
762 }
763 }
764 }
765 }
766 }
767}; // class HexagonAsmBackend
768
769} // namespace
770
771// MCAsmBackend
772MCAsmBackend *llvm::createHexagonAsmBackend(Target const &T,
773 const MCSubtargetInfo &STI,
774 MCRegisterInfo const & /*MRI*/,
775 const MCTargetOptions &Options) {
776 const Triple &TT = STI.getTargetTriple();
777 uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(TT.getOS());
778
779 StringRef CPUString = Hexagon_MC::selectHexagonCPU(STI.getCPU());
780 return new HexagonAsmBackend(T, TT, OSABI, CPUString);
781}