LLVM 19.0.0git
SparcAsmBackend.cpp
Go to the documentation of this file.
1//===-- SparcAsmBackend.cpp - Sparc 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
14#include "llvm/MC/MCExpr.h"
18#include "llvm/MC/MCValue.h"
21
22using namespace llvm;
23
24static unsigned adjustFixupValue(unsigned Kind, uint64_t Value) {
25 switch (Kind) {
26 default:
27 llvm_unreachable("Unknown fixup kind!");
28 case FK_Data_1:
29 case FK_Data_2:
30 case FK_Data_4:
31 case FK_Data_8:
32 return Value;
33
36 return (Value >> 2) & 0x3fffffff;
37
39 return (Value >> 2) & 0x3fffff;
40
42 return (Value >> 2) & 0x7ffff;
43
45 // A.3 Branch on Integer Register with Prediction (BPr)
46 // Inst{21-20} = d16hi;
47 // Inst{13-0} = d16lo;
48 unsigned d16hi = (Value >> 16) & 0x3;
49 unsigned d16lo = (Value >> 2) & 0x3fff;
50 return (d16hi << 20) | d16lo;
51 }
52
54 return (~Value >> 10) & 0x3fffff;
55
63 return (Value >> 10) & 0x3fffff;
64
67 return Value & 0x1fff;
68
70 return (Value & 0x3ff) | 0x1c00;
71
78 return Value & 0x3ff;
79
81 return (Value >> 22) & 0x3fffff;
82
84 return (Value >> 12) & 0x3ff;
85
87 return Value & 0xfff;
88
90 return (Value >> 42) & 0x3fffff;
91
93 return (Value >> 32) & 0x3ff;
94
99 assert(Value == 0 && "Sparc TLS relocs expect zero Value");
100 return 0;
101
113 return 0;
114 }
115}
116
117/// getFixupKindNumBytes - The number of bytes the fixup may change.
118static unsigned getFixupKindNumBytes(unsigned Kind) {
119 switch (Kind) {
120 default:
121 return 4;
122 case FK_Data_1:
123 return 1;
124 case FK_Data_2:
125 return 2;
126 case FK_Data_8:
127 return 8;
128 }
129}
130
131namespace {
132 class SparcAsmBackend : public MCAsmBackend {
133 protected:
134 const Target &TheTarget;
135 bool Is64Bit;
136
137 public:
138 SparcAsmBackend(const Target &T)
139 : MCAsmBackend(StringRef(T.getName()) == "sparcel"
141 : llvm::endianness::big),
142 TheTarget(T), Is64Bit(StringRef(TheTarget.getName()) == "sparcv9") {}
143
144 unsigned getNumFixupKinds() const override {
146 }
147
148 std::optional<MCFixupKind> getFixupKind(StringRef Name) const override {
149 unsigned Type;
151#define ELF_RELOC(X, Y) .Case(#X, Y)
152#include "llvm/BinaryFormat/ELFRelocs/Sparc.def"
153#undef ELF_RELOC
154 .Case("BFD_RELOC_NONE", ELF::R_SPARC_NONE)
155 .Case("BFD_RELOC_8", ELF::R_SPARC_8)
156 .Case("BFD_RELOC_16", ELF::R_SPARC_16)
157 .Case("BFD_RELOC_32", ELF::R_SPARC_32)
158 .Case("BFD_RELOC_64", ELF::R_SPARC_64)
159 .Default(-1u);
160 if (Type == -1u)
161 return std::nullopt;
162 return static_cast<MCFixupKind>(FirstLiteralRelocationKind + Type);
163 }
164
165 const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override {
166 const static MCFixupKindInfo InfosBE[Sparc::NumTargetFixupKinds] = {
167 // name offset bits flags
168 { "fixup_sparc_call30", 2, 30, MCFixupKindInfo::FKF_IsPCRel },
169 { "fixup_sparc_br22", 10, 22, MCFixupKindInfo::FKF_IsPCRel },
170 { "fixup_sparc_br19", 13, 19, MCFixupKindInfo::FKF_IsPCRel },
171 { "fixup_sparc_br16", 0, 32, MCFixupKindInfo::FKF_IsPCRel },
172 { "fixup_sparc_13", 19, 13, 0 },
173 { "fixup_sparc_hi22", 10, 22, 0 },
174 { "fixup_sparc_lo10", 22, 10, 0 },
175 { "fixup_sparc_h44", 10, 22, 0 },
176 { "fixup_sparc_m44", 22, 10, 0 },
177 { "fixup_sparc_l44", 20, 12, 0 },
178 { "fixup_sparc_hh", 10, 22, 0 },
179 { "fixup_sparc_hm", 22, 10, 0 },
180 { "fixup_sparc_lm", 10, 22, 0 },
181 { "fixup_sparc_pc22", 10, 22, MCFixupKindInfo::FKF_IsPCRel },
182 { "fixup_sparc_pc10", 22, 10, MCFixupKindInfo::FKF_IsPCRel },
183 { "fixup_sparc_got22", 10, 22, 0 },
184 { "fixup_sparc_got10", 22, 10, 0 },
185 { "fixup_sparc_got13", 19, 13, 0 },
186 { "fixup_sparc_wplt30", 2, 30, MCFixupKindInfo::FKF_IsPCRel },
187 { "fixup_sparc_tls_gd_hi22", 10, 22, 0 },
188 { "fixup_sparc_tls_gd_lo10", 22, 10, 0 },
189 { "fixup_sparc_tls_gd_add", 0, 0, 0 },
190 { "fixup_sparc_tls_gd_call", 0, 0, 0 },
191 { "fixup_sparc_tls_ldm_hi22", 10, 22, 0 },
192 { "fixup_sparc_tls_ldm_lo10", 22, 10, 0 },
193 { "fixup_sparc_tls_ldm_add", 0, 0, 0 },
194 { "fixup_sparc_tls_ldm_call", 0, 0, 0 },
195 { "fixup_sparc_tls_ldo_hix22", 10, 22, 0 },
196 { "fixup_sparc_tls_ldo_lox10", 22, 10, 0 },
197 { "fixup_sparc_tls_ldo_add", 0, 0, 0 },
198 { "fixup_sparc_tls_ie_hi22", 10, 22, 0 },
199 { "fixup_sparc_tls_ie_lo10", 22, 10, 0 },
200 { "fixup_sparc_tls_ie_ld", 0, 0, 0 },
201 { "fixup_sparc_tls_ie_ldx", 0, 0, 0 },
202 { "fixup_sparc_tls_ie_add", 0, 0, 0 },
203 { "fixup_sparc_tls_le_hix22", 0, 0, 0 },
204 { "fixup_sparc_tls_le_lox10", 0, 0, 0 },
205 { "fixup_sparc_hix22", 10, 22, 0 },
206 { "fixup_sparc_lox10", 19, 13, 0 },
207 { "fixup_sparc_gotdata_hix22", 0, 0, 0 },
208 { "fixup_sparc_gotdata_lox10", 0, 0, 0 },
209 { "fixup_sparc_gotdata_op", 0, 0, 0 },
210 };
211
212 const static MCFixupKindInfo InfosLE[Sparc::NumTargetFixupKinds] = {
213 // name offset bits flags
214 { "fixup_sparc_call30", 0, 30, MCFixupKindInfo::FKF_IsPCRel },
215 { "fixup_sparc_br22", 0, 22, MCFixupKindInfo::FKF_IsPCRel },
216 { "fixup_sparc_br19", 0, 19, MCFixupKindInfo::FKF_IsPCRel },
217 { "fixup_sparc_br16", 32, 0, MCFixupKindInfo::FKF_IsPCRel },
218 { "fixup_sparc_13", 0, 13, 0 },
219 { "fixup_sparc_hi22", 0, 22, 0 },
220 { "fixup_sparc_lo10", 0, 10, 0 },
221 { "fixup_sparc_h44", 0, 22, 0 },
222 { "fixup_sparc_m44", 0, 10, 0 },
223 { "fixup_sparc_l44", 0, 12, 0 },
224 { "fixup_sparc_hh", 0, 22, 0 },
225 { "fixup_sparc_hm", 0, 10, 0 },
226 { "fixup_sparc_lm", 0, 22, 0 },
227 { "fixup_sparc_pc22", 0, 22, MCFixupKindInfo::FKF_IsPCRel },
228 { "fixup_sparc_pc10", 0, 10, MCFixupKindInfo::FKF_IsPCRel },
229 { "fixup_sparc_got22", 0, 22, 0 },
230 { "fixup_sparc_got10", 0, 10, 0 },
231 { "fixup_sparc_got13", 0, 13, 0 },
232 { "fixup_sparc_wplt30", 0, 30, MCFixupKindInfo::FKF_IsPCRel },
233 { "fixup_sparc_tls_gd_hi22", 0, 22, 0 },
234 { "fixup_sparc_tls_gd_lo10", 0, 10, 0 },
235 { "fixup_sparc_tls_gd_add", 0, 0, 0 },
236 { "fixup_sparc_tls_gd_call", 0, 0, 0 },
237 { "fixup_sparc_tls_ldm_hi22", 0, 22, 0 },
238 { "fixup_sparc_tls_ldm_lo10", 0, 10, 0 },
239 { "fixup_sparc_tls_ldm_add", 0, 0, 0 },
240 { "fixup_sparc_tls_ldm_call", 0, 0, 0 },
241 { "fixup_sparc_tls_ldo_hix22", 0, 22, 0 },
242 { "fixup_sparc_tls_ldo_lox10", 0, 10, 0 },
243 { "fixup_sparc_tls_ldo_add", 0, 0, 0 },
244 { "fixup_sparc_tls_ie_hi22", 0, 22, 0 },
245 { "fixup_sparc_tls_ie_lo10", 0, 10, 0 },
246 { "fixup_sparc_tls_ie_ld", 0, 0, 0 },
247 { "fixup_sparc_tls_ie_ldx", 0, 0, 0 },
248 { "fixup_sparc_tls_ie_add", 0, 0, 0 },
249 { "fixup_sparc_tls_le_hix22", 0, 0, 0 },
250 { "fixup_sparc_tls_le_lox10", 0, 0, 0 },
251 { "fixup_sparc_hix22", 0, 22, 0 },
252 { "fixup_sparc_lox10", 0, 13, 0 },
253 { "fixup_sparc_gotdata_hix22", 0, 0, 0 },
254 { "fixup_sparc_gotdata_lox10", 0, 0, 0 },
255 { "fixup_sparc_gotdata_op", 0, 0, 0 },
256 };
257
258 // Fixup kinds from .reloc directive are like R_SPARC_NONE. They do
259 // not require any extra processing.
260 if (Kind >= FirstLiteralRelocationKind)
262
263 if (Kind < FirstTargetFixupKind)
265
266 assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
267 "Invalid kind!");
268 if (Endian == llvm::endianness::little)
269 return InfosLE[Kind - FirstTargetFixupKind];
270
271 return InfosBE[Kind - FirstTargetFixupKind];
272 }
273
274 bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
275 const MCValue &Target,
276 const MCSubtargetInfo *STI) override {
277 if (Fixup.getKind() >= FirstLiteralRelocationKind)
278 return true;
279 switch ((Sparc::Fixups)Fixup.getKind()) {
280 default:
281 return false;
283 if (Target.getSymA()->getSymbol().isTemporary())
284 return false;
285 [[fallthrough]];
304 return true;
305 }
306 }
307
308 /// fixupNeedsRelaxation - Target specific predicate for whether a given
309 /// fixup requires the associated instruction to be relaxed.
312 const MCRelaxableFragment *DF,
313 const MCAsmLayout &Layout) const override {
314 // FIXME.
315 llvm_unreachable("fixupNeedsRelaxation() unimplemented");
316 return false;
317 }
318 void relaxInstruction(MCInst &Inst,
319 const MCSubtargetInfo &STI) const override {
320 // FIXME.
321 llvm_unreachable("relaxInstruction() unimplemented");
322 }
323
324 bool writeNopData(raw_ostream &OS, uint64_t Count,
325 const MCSubtargetInfo *STI) const override {
326
327 // If the count is not 4-byte aligned, we must be writing data into the
328 // text section (otherwise we have unaligned instructions, and thus have
329 // far bigger problems), so just write zeros instead.
330 OS.write_zeros(Count % 4);
331
332 uint64_t NumNops = Count / 4;
333 for (uint64_t i = 0; i != NumNops; ++i)
334 support::endian::write<uint32_t>(OS, 0x01000000, Endian);
335
336 return true;
337 }
338 };
339
340 class ELFSparcAsmBackend : public SparcAsmBackend {
341 Triple::OSType OSType;
342 public:
343 ELFSparcAsmBackend(const Target &T, Triple::OSType OSType) :
344 SparcAsmBackend(T), OSType(OSType) { }
345
346 void applyFixup(const MCAssembler &Asm, const MCFixup &Fixup,
348 uint64_t Value, bool IsResolved,
349 const MCSubtargetInfo *STI) const override {
350
351 if (Fixup.getKind() >= FirstLiteralRelocationKind)
352 return;
353 Value = adjustFixupValue(Fixup.getKind(), Value);
354 if (!Value) return; // Doesn't change encoding.
355
356 unsigned NumBytes = getFixupKindNumBytes(Fixup.getKind());
357 unsigned Offset = Fixup.getOffset();
358 // For each byte of the fragment that the fixup touches, mask in the bits
359 // from the fixup value. The Value has been "split up" into the
360 // appropriate bitfields above.
361 for (unsigned i = 0; i != NumBytes; ++i) {
362 unsigned Idx =
363 Endian == llvm::endianness::little ? i : (NumBytes - 1) - i;
364 Data[Offset + Idx] |= uint8_t((Value >> (i * 8)) & 0xff);
365 }
366 }
367
368 std::unique_ptr<MCObjectTargetWriter>
369 createObjectTargetWriter() const override {
370 uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(OSType);
371 return createSparcELFObjectWriter(Is64Bit, OSABI);
372 }
373 };
374
375} // end anonymous namespace
376
378 const MCSubtargetInfo &STI,
379 const MCRegisterInfo &MRI,
380 const MCTargetOptions &Options) {
381 return new ELFSparcAsmBackend(T, STI.getTargetTriple().getOS());
382}
unsigned const MachineRegisterInfo * MRI
Returns the sub type a function will return at a given Idx Should correspond to the result type of an ExtractValue instruction executed with just that one unsigned Idx
static RegisterPass< DebugifyFunctionPass > DF("debugify-function", "Attach debug info to a function")
std::string Name
static LVOptions Options
Definition: LVOptions.cpp:25
PowerPC TLS Dynamic Call Fixup
static StringRef getName(Value *V)
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
endianness Endian
raw_pwrite_stream & OS
static unsigned adjustFixupValue(unsigned Kind, uint64_t Value)
static unsigned getFixupKindNumBytes(unsigned Kind)
getFixupKindNumBytes - The number of bytes the fixup may change.
This file implements the StringSwitch template, which mimics a switch() statement whose cases are str...
Generic interface to target specific assembler backends.
Definition: MCAsmBackend.h:43
virtual bool writeNopData(raw_ostream &OS, uint64_t Count, const MCSubtargetInfo *STI) const =0
Write an (optimal) nop sequence of Count bytes to the given output.
virtual void relaxInstruction(MCInst &Inst, const MCSubtargetInfo &STI) const
Relax the instruction in the given fragment to the next wider instruction.
Definition: MCAsmBackend.h:186
virtual bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value, const MCRelaxableFragment *DF, const MCAsmLayout &Layout) const =0
Simple predicate for targets where !Resolved implies requiring relaxation.
virtual bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup, const MCValue &Target, const MCSubtargetInfo *STI)
Hook to check if a relocation is needed for some target specific reason.
Definition: MCAsmBackend.h:102
virtual unsigned getNumFixupKinds() const =0
Get the number of target specific fixup kinds.
virtual const MCFixupKindInfo & getFixupKindInfo(MCFixupKind Kind) const
Get information on a fixup kind.
virtual std::optional< MCFixupKind > getFixupKind(StringRef Name) const
Map a relocation name used in .reloc to a fixup kind.
Encapsulates the layout of an assembly file at a particular point in time.
Definition: MCAsmLayout.h:28
Encode information on a single operation to perform on a byte sequence (e.g., an encoded instruction)...
Definition: MCFixup.h:71
Instances of this class represent a single low-level machine instruction.
Definition: MCInst.h:184
MCRegisterInfo base class - We assume that the target defines a static array of MCRegisterDesc object...
A relaxable fragment holds on to its MCInst, since it may need to be relaxed during the assembler lay...
Definition: MCFragment.h:267
Generic base class for all target subtargets.
const Triple & getTargetTriple() const
This represents an "assembler immediate".
Definition: MCValue.h:36
MutableArrayRef - Represent a mutable reference to an array (0 or more elements consecutively in memo...
Definition: ArrayRef.h:307
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:50
A switch()-like statement whose cases are string literals.
Definition: StringSwitch.h:44
StringSwitch & Case(StringLiteral S, T Value)
Definition: StringSwitch.h:69
R Default(T Value)
Definition: StringSwitch.h:182
Target - Wrapper for Target specific information.
OSType getOS() const
Get the parsed operating system type of this triple.
Definition: Triple.h:382
The instances of the Type class are immutable: once they are created, they are never changed.
Definition: Type.h:45
LLVM Value Representation.
Definition: Value.h:74
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
raw_ostream & write_zeros(unsigned NumZeros)
write_zeros - Insert 'NumZeros' nulls.
#define llvm_unreachable(msg)
Marks that the current location is not supposed to be reachable.
@ fixup_sparc_lo10
fixup_sparc_lo10 - 10-bit fixup corresponding to lo(foo)
@ fixup_sparc_br16
fixup_sparc_bpr - 16-bit fixup for bpr
@ fixup_sparc_lm
fixup_sparc_lm - 22-bit fixup corresponding to lm(foo)
@ fixup_sparc_lox10
13-bit fixup corresponding to lox(foo)
@ fixup_sparc_hi22
fixup_sparc_hi22 - 22-bit fixup corresponding to hi(foo) for sethi
@ fixup_sparc_tls_ldo_lox10
@ fixup_sparc_tls_le_hix22
@ fixup_sparc_m44
fixup_sparc_m44 - 10-bit fixup corresponding to m44(foo)
@ fixup_sparc_gotdata_hix22
22-bit fixup corresponding to gdop_hix22(foo)
@ fixup_sparc_hh
fixup_sparc_hh - 22-bit fixup corresponding to hh(foo)
@ fixup_sparc_got10
fixup_sparc_got10 - 10-bit fixup corresponding to got10(foo)
@ fixup_sparc_tls_le_lox10
@ fixup_sparc_got13
fixup_sparc_got13 - 13-bit fixup corresponding to got13(foo)
@ fixup_sparc_tls_ldo_hix22
@ fixup_sparc_gotdata_op
32-bit fixup corresponding to gdop(foo)
@ fixup_sparc_tls_gd_hi22
fixups for Thread Local Storage
@ fixup_sparc_br19
fixup_sparc_br19 - 19-bit PC relative relocation for branches on icc/xcc
@ fixup_sparc_13
fixup_sparc_13 - 13-bit fixup
@ fixup_sparc_hix22
22-bit fixup corresponding to hix(foo)
@ fixup_sparc_got22
fixup_sparc_got22 - 22-bit fixup corresponding to got22(foo)
@ fixup_sparc_h44
fixup_sparc_h44 - 22-bit fixup corresponding to h44(foo)
@ fixup_sparc_tls_ldm_lo10
@ fixup_sparc_tls_ldm_call
@ fixup_sparc_pc22
fixup_sparc_pc22 - 22-bit fixup corresponding to pc22(foo)
@ fixup_sparc_tls_ldm_hi22
@ fixup_sparc_br22
fixup_sparc_br22 - 22-bit PC relative relocation for branches
@ fixup_sparc_l44
fixup_sparc_l44 - 12-bit fixup corresponding to l44(foo)
@ fixup_sparc_gotdata_lox10
13-bit fixup corresponding to gdop_lox10(foo)
@ fixup_sparc_pc10
fixup_sparc_pc10 - 10-bit fixup corresponding to pc10(foo)
@ fixup_sparc_hm
fixup_sparc_hm - 10-bit fixup corresponding to hm(foo)
@ fixup_sparc_wplt30
fixup_sparc_wplt30
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ Offset
Definition: DWP.cpp:456
MCFixupKind
Extensible enumeration to represent the type of a fixup.
Definition: MCFixup.h:21
@ FirstTargetFixupKind
Definition: MCFixup.h:45
@ FirstLiteralRelocationKind
The range [FirstLiteralRelocationKind, MaxTargetFixupKind) is used for relocations coming from ....
Definition: MCFixup.h:50
@ FK_Data_8
A eight-byte fixup.
Definition: MCFixup.h:26
@ FK_Data_1
A one-byte fixup.
Definition: MCFixup.h:23
@ FK_Data_4
A four-byte fixup.
Definition: MCFixup.h:25
@ FK_NONE
A no-op fixup.
Definition: MCFixup.h:22
@ FK_Data_2
A two-byte fixup.
Definition: MCFixup.h:24
MCAsmBackend * createSparcAsmBackend(const Target &T, const MCSubtargetInfo &STI, const MCRegisterInfo &MRI, const MCTargetOptions &Options)
std::unique_ptr< MCObjectTargetWriter > createSparcELFObjectWriter(bool Is64Bit, uint8_t OSABI)
endianness
Definition: bit.h:70
Target independent information on a fixup kind.
@ FKF_IsPCRel
Is this fixup kind PCrelative? This is used by the assembler backend to evaluate fixup values in a ta...