xref: /freebsd/contrib/llvm-project/llvm/lib/Target/Sparc/MCTargetDesc/SparcAsmBackend.cpp (revision cfd6422a5217410fbd66f7a7a8a64d9d85e61229)
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 
9 #include "MCTargetDesc/SparcFixupKinds.h"
10 #include "MCTargetDesc/SparcMCTargetDesc.h"
11 #include "llvm/MC/MCAsmBackend.h"
12 #include "llvm/MC/MCELFObjectWriter.h"
13 #include "llvm/MC/MCExpr.h"
14 #include "llvm/MC/MCFixupKindInfo.h"
15 #include "llvm/MC/MCObjectWriter.h"
16 #include "llvm/MC/MCSubtargetInfo.h"
17 #include "llvm/MC/MCValue.h"
18 #include "llvm/Support/EndianStream.h"
19 #include "llvm/Support/TargetRegistry.h"
20 
21 using namespace llvm;
22 
23 static unsigned adjustFixupValue(unsigned Kind, uint64_t Value) {
24   switch (Kind) {
25   default:
26     llvm_unreachable("Unknown fixup kind!");
27   case FK_Data_1:
28   case FK_Data_2:
29   case FK_Data_4:
30   case FK_Data_8:
31     return Value;
32 
33   case Sparc::fixup_sparc_wplt30:
34   case Sparc::fixup_sparc_call30:
35     return (Value >> 2) & 0x3fffffff;
36 
37   case Sparc::fixup_sparc_br22:
38     return (Value >> 2) & 0x3fffff;
39 
40   case Sparc::fixup_sparc_br19:
41     return (Value >> 2) & 0x7ffff;
42 
43   case Sparc::fixup_sparc_br16_2:
44     return (Value >> 2) & 0xc000;
45 
46   case Sparc::fixup_sparc_br16_14:
47     return (Value >> 2) & 0x3fff;
48 
49   case Sparc::fixup_sparc_pc22:
50   case Sparc::fixup_sparc_got22:
51   case Sparc::fixup_sparc_tls_gd_hi22:
52   case Sparc::fixup_sparc_tls_ldm_hi22:
53   case Sparc::fixup_sparc_tls_ie_hi22:
54   case Sparc::fixup_sparc_hi22:
55     return (Value >> 10) & 0x3fffff;
56 
57   case Sparc::fixup_sparc_got13:
58   case Sparc::fixup_sparc_13:
59     return Value & 0x1fff;
60 
61   case Sparc::fixup_sparc_pc10:
62   case Sparc::fixup_sparc_got10:
63   case Sparc::fixup_sparc_tls_gd_lo10:
64   case Sparc::fixup_sparc_tls_ldm_lo10:
65   case Sparc::fixup_sparc_tls_ie_lo10:
66   case Sparc::fixup_sparc_lo10:
67     return Value & 0x3ff;
68 
69   case Sparc::fixup_sparc_h44:
70     return (Value >> 22) & 0x3fffff;
71 
72   case Sparc::fixup_sparc_m44:
73     return (Value >> 12) & 0x3ff;
74 
75   case Sparc::fixup_sparc_l44:
76     return Value & 0xfff;
77 
78   case Sparc::fixup_sparc_hh:
79     return (Value >> 42) & 0x3fffff;
80 
81   case Sparc::fixup_sparc_hm:
82     return (Value >> 32) & 0x3ff;
83 
84   case Sparc::fixup_sparc_tls_ldo_hix22:
85   case Sparc::fixup_sparc_tls_le_hix22:
86   case Sparc::fixup_sparc_tls_ldo_lox10:
87   case Sparc::fixup_sparc_tls_le_lox10:
88     assert(Value == 0 && "Sparc TLS relocs expect zero Value");
89     return 0;
90 
91   case Sparc::fixup_sparc_tls_gd_add:
92   case Sparc::fixup_sparc_tls_gd_call:
93   case Sparc::fixup_sparc_tls_ldm_add:
94   case Sparc::fixup_sparc_tls_ldm_call:
95   case Sparc::fixup_sparc_tls_ldo_add:
96   case Sparc::fixup_sparc_tls_ie_ld:
97   case Sparc::fixup_sparc_tls_ie_ldx:
98   case Sparc::fixup_sparc_tls_ie_add:
99     return 0;
100   }
101 }
102 
103 /// getFixupKindNumBytes - The number of bytes the fixup may change.
104 static unsigned getFixupKindNumBytes(unsigned Kind) {
105     switch (Kind) {
106   default:
107     return 4;
108   case FK_Data_1:
109     return 1;
110   case FK_Data_2:
111     return 2;
112   case FK_Data_8:
113     return 8;
114   }
115 }
116 
117 namespace {
118   class SparcAsmBackend : public MCAsmBackend {
119   protected:
120     const Target &TheTarget;
121     bool Is64Bit;
122 
123   public:
124     SparcAsmBackend(const Target &T)
125         : MCAsmBackend(StringRef(T.getName()) == "sparcel" ? support::little
126                                                            : support::big),
127           TheTarget(T), Is64Bit(StringRef(TheTarget.getName()) == "sparcv9") {}
128 
129     unsigned getNumFixupKinds() const override {
130       return Sparc::NumTargetFixupKinds;
131     }
132 
133     const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override {
134       const static MCFixupKindInfo InfosBE[Sparc::NumTargetFixupKinds] = {
135         // name                    offset bits  flags
136         { "fixup_sparc_call30",     2,     30,  MCFixupKindInfo::FKF_IsPCRel },
137         { "fixup_sparc_br22",      10,     22,  MCFixupKindInfo::FKF_IsPCRel },
138         { "fixup_sparc_br19",      13,     19,  MCFixupKindInfo::FKF_IsPCRel },
139         { "fixup_sparc_br16_2",    10,      2,  MCFixupKindInfo::FKF_IsPCRel },
140         { "fixup_sparc_br16_14",   18,     14,  MCFixupKindInfo::FKF_IsPCRel },
141         { "fixup_sparc_13",        19,     13,  0 },
142         { "fixup_sparc_hi22",      10,     22,  0 },
143         { "fixup_sparc_lo10",      22,     10,  0 },
144         { "fixup_sparc_h44",       10,     22,  0 },
145         { "fixup_sparc_m44",       22,     10,  0 },
146         { "fixup_sparc_l44",       20,     12,  0 },
147         { "fixup_sparc_hh",        10,     22,  0 },
148         { "fixup_sparc_hm",        22,     10,  0 },
149         { "fixup_sparc_pc22",      10,     22,  MCFixupKindInfo::FKF_IsPCRel },
150         { "fixup_sparc_pc10",      22,     10,  MCFixupKindInfo::FKF_IsPCRel },
151         { "fixup_sparc_got22",     10,     22,  0 },
152         { "fixup_sparc_got10",     22,     10,  0 },
153         { "fixup_sparc_got13",     19,     13,  0 },
154         { "fixup_sparc_wplt30",     2,     30,  MCFixupKindInfo::FKF_IsPCRel },
155         { "fixup_sparc_tls_gd_hi22",   10, 22,  0 },
156         { "fixup_sparc_tls_gd_lo10",   22, 10,  0 },
157         { "fixup_sparc_tls_gd_add",     0,  0,  0 },
158         { "fixup_sparc_tls_gd_call",    0,  0,  0 },
159         { "fixup_sparc_tls_ldm_hi22",  10, 22,  0 },
160         { "fixup_sparc_tls_ldm_lo10",  22, 10,  0 },
161         { "fixup_sparc_tls_ldm_add",    0,  0,  0 },
162         { "fixup_sparc_tls_ldm_call",   0,  0,  0 },
163         { "fixup_sparc_tls_ldo_hix22", 10, 22,  0 },
164         { "fixup_sparc_tls_ldo_lox10", 22, 10,  0 },
165         { "fixup_sparc_tls_ldo_add",    0,  0,  0 },
166         { "fixup_sparc_tls_ie_hi22",   10, 22,  0 },
167         { "fixup_sparc_tls_ie_lo10",   22, 10,  0 },
168         { "fixup_sparc_tls_ie_ld",      0,  0,  0 },
169         { "fixup_sparc_tls_ie_ldx",     0,  0,  0 },
170         { "fixup_sparc_tls_ie_add",     0,  0,  0 },
171         { "fixup_sparc_tls_le_hix22",   0,  0,  0 },
172         { "fixup_sparc_tls_le_lox10",   0,  0,  0 }
173       };
174 
175       const static MCFixupKindInfo InfosLE[Sparc::NumTargetFixupKinds] = {
176         // name                    offset bits  flags
177         { "fixup_sparc_call30",     0,     30,  MCFixupKindInfo::FKF_IsPCRel },
178         { "fixup_sparc_br22",       0,     22,  MCFixupKindInfo::FKF_IsPCRel },
179         { "fixup_sparc_br19",       0,     19,  MCFixupKindInfo::FKF_IsPCRel },
180         { "fixup_sparc_br16_2",    20,      2,  MCFixupKindInfo::FKF_IsPCRel },
181         { "fixup_sparc_br16_14",    0,     14,  MCFixupKindInfo::FKF_IsPCRel },
182         { "fixup_sparc_13",         0,     13,  0 },
183         { "fixup_sparc_hi22",       0,     22,  0 },
184         { "fixup_sparc_lo10",       0,     10,  0 },
185         { "fixup_sparc_h44",        0,     22,  0 },
186         { "fixup_sparc_m44",        0,     10,  0 },
187         { "fixup_sparc_l44",        0,     12,  0 },
188         { "fixup_sparc_hh",         0,     22,  0 },
189         { "fixup_sparc_hm",         0,     10,  0 },
190         { "fixup_sparc_pc22",       0,     22,  MCFixupKindInfo::FKF_IsPCRel },
191         { "fixup_sparc_pc10",       0,     10,  MCFixupKindInfo::FKF_IsPCRel },
192         { "fixup_sparc_got22",      0,     22,  0 },
193         { "fixup_sparc_got10",      0,     10,  0 },
194         { "fixup_sparc_got13",      0,     13,  0 },
195         { "fixup_sparc_wplt30",      0,     30,  MCFixupKindInfo::FKF_IsPCRel },
196         { "fixup_sparc_tls_gd_hi22",    0, 22,  0 },
197         { "fixup_sparc_tls_gd_lo10",    0, 10,  0 },
198         { "fixup_sparc_tls_gd_add",     0,  0,  0 },
199         { "fixup_sparc_tls_gd_call",    0,  0,  0 },
200         { "fixup_sparc_tls_ldm_hi22",   0, 22,  0 },
201         { "fixup_sparc_tls_ldm_lo10",   0, 10,  0 },
202         { "fixup_sparc_tls_ldm_add",    0,  0,  0 },
203         { "fixup_sparc_tls_ldm_call",   0,  0,  0 },
204         { "fixup_sparc_tls_ldo_hix22",  0, 22,  0 },
205         { "fixup_sparc_tls_ldo_lox10",  0, 10,  0 },
206         { "fixup_sparc_tls_ldo_add",    0,  0,  0 },
207         { "fixup_sparc_tls_ie_hi22",    0, 22,  0 },
208         { "fixup_sparc_tls_ie_lo10",    0, 10,  0 },
209         { "fixup_sparc_tls_ie_ld",      0,  0,  0 },
210         { "fixup_sparc_tls_ie_ldx",     0,  0,  0 },
211         { "fixup_sparc_tls_ie_add",     0,  0,  0 },
212         { "fixup_sparc_tls_le_hix22",   0,  0,  0 },
213         { "fixup_sparc_tls_le_lox10",   0,  0,  0 }
214       };
215 
216       if (Kind < FirstTargetFixupKind)
217         return MCAsmBackend::getFixupKindInfo(Kind);
218 
219       assert(unsigned(Kind - FirstTargetFixupKind) < getNumFixupKinds() &&
220              "Invalid kind!");
221       if (Endian == support::little)
222         return InfosLE[Kind - FirstTargetFixupKind];
223 
224       return InfosBE[Kind - FirstTargetFixupKind];
225     }
226 
227     bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
228                                const MCValue &Target) override {
229       switch ((Sparc::Fixups)Fixup.getKind()) {
230       default:
231         return false;
232       case Sparc::fixup_sparc_wplt30:
233         if (Target.getSymA()->getSymbol().isTemporary())
234           return false;
235         LLVM_FALLTHROUGH;
236       case Sparc::fixup_sparc_tls_gd_hi22:
237       case Sparc::fixup_sparc_tls_gd_lo10:
238       case Sparc::fixup_sparc_tls_gd_add:
239       case Sparc::fixup_sparc_tls_gd_call:
240       case Sparc::fixup_sparc_tls_ldm_hi22:
241       case Sparc::fixup_sparc_tls_ldm_lo10:
242       case Sparc::fixup_sparc_tls_ldm_add:
243       case Sparc::fixup_sparc_tls_ldm_call:
244       case Sparc::fixup_sparc_tls_ldo_hix22:
245       case Sparc::fixup_sparc_tls_ldo_lox10:
246       case Sparc::fixup_sparc_tls_ldo_add:
247       case Sparc::fixup_sparc_tls_ie_hi22:
248       case Sparc::fixup_sparc_tls_ie_lo10:
249       case Sparc::fixup_sparc_tls_ie_ld:
250       case Sparc::fixup_sparc_tls_ie_ldx:
251       case Sparc::fixup_sparc_tls_ie_add:
252       case Sparc::fixup_sparc_tls_le_hix22:
253       case Sparc::fixup_sparc_tls_le_lox10:
254         return true;
255       }
256     }
257 
258     bool mayNeedRelaxation(const MCInst &Inst,
259                            const MCSubtargetInfo &STI) const override {
260       // FIXME.
261       return false;
262     }
263 
264     /// fixupNeedsRelaxation - Target specific predicate for whether a given
265     /// fixup requires the associated instruction to be relaxed.
266     bool fixupNeedsRelaxation(const MCFixup &Fixup,
267                               uint64_t Value,
268                               const MCRelaxableFragment *DF,
269                               const MCAsmLayout &Layout) const override {
270       // FIXME.
271       llvm_unreachable("fixupNeedsRelaxation() unimplemented");
272       return false;
273     }
274     void relaxInstruction(MCInst &Inst,
275                           const MCSubtargetInfo &STI) const override {
276       // FIXME.
277       llvm_unreachable("relaxInstruction() unimplemented");
278     }
279 
280     bool writeNopData(raw_ostream &OS, uint64_t Count) const override {
281       // Cannot emit NOP with size not multiple of 32 bits.
282       if (Count % 4 != 0)
283         return false;
284 
285       uint64_t NumNops = Count / 4;
286       for (uint64_t i = 0; i != NumNops; ++i)
287         support::endian::write<uint32_t>(OS, 0x01000000, Endian);
288 
289       return true;
290     }
291   };
292 
293   class ELFSparcAsmBackend : public SparcAsmBackend {
294     Triple::OSType OSType;
295   public:
296     ELFSparcAsmBackend(const Target &T, Triple::OSType OSType) :
297       SparcAsmBackend(T), OSType(OSType) { }
298 
299     void applyFixup(const MCAssembler &Asm, const MCFixup &Fixup,
300                     const MCValue &Target, MutableArrayRef<char> Data,
301                     uint64_t Value, bool IsResolved,
302                     const MCSubtargetInfo *STI) const override {
303 
304       Value = adjustFixupValue(Fixup.getKind(), Value);
305       if (!Value) return;           // Doesn't change encoding.
306 
307       unsigned NumBytes = getFixupKindNumBytes(Fixup.getKind());
308       unsigned Offset = Fixup.getOffset();
309       // For each byte of the fragment that the fixup touches, mask in the bits
310       // from the fixup value. The Value has been "split up" into the
311       // appropriate bitfields above.
312       for (unsigned i = 0; i != NumBytes; ++i) {
313         unsigned Idx = Endian == support::little ? i : (NumBytes - 1) - i;
314         Data[Offset + Idx] |= uint8_t((Value >> (i * 8)) & 0xff);
315       }
316     }
317 
318     std::unique_ptr<MCObjectTargetWriter>
319     createObjectTargetWriter() const override {
320       uint8_t OSABI = MCELFObjectTargetWriter::getOSABI(OSType);
321       return createSparcELFObjectWriter(Is64Bit, OSABI);
322     }
323   };
324 
325 } // end anonymous namespace
326 
327 MCAsmBackend *llvm::createSparcAsmBackend(const Target &T,
328                                           const MCSubtargetInfo &STI,
329                                           const MCRegisterInfo &MRI,
330                                           const MCTargetOptions &Options) {
331   return new ELFSparcAsmBackend(T, STI.getTargetTriple().getOS());
332 }
333