xref: /NextBSD/contrib/llvm/tools/lldb/source/Plugins/ABI/SysV-ppc64/ABISysV_ppc64.cpp (revision 84d351007654069f9643c8e4b4802a7f5f08ee42)
1 //===-- ABISysV_ppc64.cpp --------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "ABISysV_ppc64.h"
11 
12 #include "lldb/Core/ConstString.h"
13 #include "lldb/Core/DataExtractor.h"
14 #include "lldb/Core/Error.h"
15 #include "lldb/Core/Log.h"
16 #include "lldb/Core/Module.h"
17 #include "lldb/Core/PluginManager.h"
18 #include "lldb/Core/RegisterValue.h"
19 #include "lldb/Core/Value.h"
20 #include "lldb/Core/ValueObjectConstResult.h"
21 #include "lldb/Core/ValueObjectRegister.h"
22 #include "lldb/Core/ValueObjectMemory.h"
23 #include "lldb/Symbol/ClangASTContext.h"
24 #include "lldb/Symbol/UnwindPlan.h"
25 #include "lldb/Target/Target.h"
26 #include "lldb/Target/Process.h"
27 #include "lldb/Target/RegisterContext.h"
28 #include "lldb/Target/StackFrame.h"
29 #include "lldb/Target/Thread.h"
30 
31 #include "llvm/ADT/STLExtras.h"
32 #include "llvm/ADT/Triple.h"
33 
34 using namespace lldb;
35 using namespace lldb_private;
36 
37 enum gcc_dwarf_regnums
38 {
39     gcc_dwarf_r0 = 0,
40     gcc_dwarf_r1,
41     gcc_dwarf_r2,
42     gcc_dwarf_r3,
43     gcc_dwarf_r4,
44     gcc_dwarf_r5,
45     gcc_dwarf_r6,
46     gcc_dwarf_r7,
47     gcc_dwarf_r8,
48     gcc_dwarf_r9,
49     gcc_dwarf_r10,
50     gcc_dwarf_r11,
51     gcc_dwarf_r12,
52     gcc_dwarf_r13,
53     gcc_dwarf_r14,
54     gcc_dwarf_r15,
55     gcc_dwarf_r16,
56     gcc_dwarf_r17,
57     gcc_dwarf_r18,
58     gcc_dwarf_r19,
59     gcc_dwarf_r20,
60     gcc_dwarf_r21,
61     gcc_dwarf_r22,
62     gcc_dwarf_r23,
63     gcc_dwarf_r24,
64     gcc_dwarf_r25,
65     gcc_dwarf_r26,
66     gcc_dwarf_r27,
67     gcc_dwarf_r28,
68     gcc_dwarf_r29,
69     gcc_dwarf_r30,
70     gcc_dwarf_r31,
71     gcc_dwarf_f0,
72     gcc_dwarf_f1,
73     gcc_dwarf_f2,
74     gcc_dwarf_f3,
75     gcc_dwarf_f4,
76     gcc_dwarf_f5,
77     gcc_dwarf_f6,
78     gcc_dwarf_f7,
79     gcc_dwarf_f8,
80     gcc_dwarf_f9,
81     gcc_dwarf_f10,
82     gcc_dwarf_f11,
83     gcc_dwarf_f12,
84     gcc_dwarf_f13,
85     gcc_dwarf_f14,
86     gcc_dwarf_f15,
87     gcc_dwarf_f16,
88     gcc_dwarf_f17,
89     gcc_dwarf_f18,
90     gcc_dwarf_f19,
91     gcc_dwarf_f20,
92     gcc_dwarf_f21,
93     gcc_dwarf_f22,
94     gcc_dwarf_f23,
95     gcc_dwarf_f24,
96     gcc_dwarf_f25,
97     gcc_dwarf_f26,
98     gcc_dwarf_f27,
99     gcc_dwarf_f28,
100     gcc_dwarf_f29,
101     gcc_dwarf_f30,
102     gcc_dwarf_f31,
103     gcc_dwarf_cr,
104     gcc_dwarf_fpscr,
105     gcc_dwarf_xer = 101,
106     gcc_dwarf_lr = 108,
107     gcc_dwarf_ctr,
108     gcc_dwarf_pc,
109     gcc_dwarf_cfa,
110 };
111 
112 enum gdb_regnums
113 {
114     gdb_r0 = 0,
115     gdb_r1,
116     gdb_r2,
117     gdb_r3,
118     gdb_r4,
119     gdb_r5,
120     gdb_r6,
121     gdb_r7,
122     gdb_r8,
123     gdb_r9,
124     gdb_r10,
125     gdb_r11,
126     gdb_r12,
127     gdb_r13,
128     gdb_r14,
129     gdb_r15,
130     gdb_r16,
131     gdb_r17,
132     gdb_r18,
133     gdb_r19,
134     gdb_r20,
135     gdb_r21,
136     gdb_r22,
137     gdb_r23,
138     gdb_r24,
139     gdb_r25,
140     gdb_r26,
141     gdb_r27,
142     gdb_r28,
143     gdb_r29,
144     gdb_r30,
145     gdb_r31,
146     gdb_lr,
147     gdb_cr,
148     gdb_xer,
149     gdb_ctr,
150     gdb_pc,
151 };
152 
153 
154 // Note that the size and offset will be updated by platform-specific classes.
155 #define DEFINE_GPR(reg, alt, kind1, kind2, kind3, kind4)           \
156     { #reg, alt, 8, 0, eEncodingUint, \
157       eFormatHex, { kind1, kind2, kind3, kind4}, NULL, NULL }
158 static const RegisterInfo
159 g_register_infos[] =
160 {
161     // General purpose registers.                 GCC,                  DWARF,              Generic,                GDB
162     DEFINE_GPR(r0,       NULL,  gcc_dwarf_r0,    gcc_dwarf_r0,    LLDB_INVALID_REGNUM,    gdb_r0),
163     DEFINE_GPR(r1,       "sp",  gcc_dwarf_r1,    gcc_dwarf_r1,    LLDB_REGNUM_GENERIC_SP, gdb_r1),
164     DEFINE_GPR(r2,       NULL,  gcc_dwarf_r2,    gcc_dwarf_r2,    LLDB_INVALID_REGNUM,    gdb_r2),
165     DEFINE_GPR(r3,       "arg1",gcc_dwarf_r3,    gcc_dwarf_r3,    LLDB_REGNUM_GENERIC_ARG1, gdb_r3),
166     DEFINE_GPR(r4,       "arg2",gcc_dwarf_r4,    gcc_dwarf_r4,    LLDB_REGNUM_GENERIC_ARG2 ,gdb_r4),
167     DEFINE_GPR(r5,       "arg3",gcc_dwarf_r5,    gcc_dwarf_r5,    LLDB_REGNUM_GENERIC_ARG3, gdb_r5),
168     DEFINE_GPR(r6,       "arg4",gcc_dwarf_r6,    gcc_dwarf_r6,    LLDB_REGNUM_GENERIC_ARG4, gdb_r6),
169     DEFINE_GPR(r7,       "arg5",gcc_dwarf_r7,    gcc_dwarf_r7,    LLDB_REGNUM_GENERIC_ARG5, gdb_r7),
170     DEFINE_GPR(r8,       "arg6",gcc_dwarf_r8,    gcc_dwarf_r8,    LLDB_REGNUM_GENERIC_ARG6, gdb_r8),
171     DEFINE_GPR(r9,       "arg7",gcc_dwarf_r9,    gcc_dwarf_r9,    LLDB_REGNUM_GENERIC_ARG7, gdb_r9),
172     DEFINE_GPR(r10,      "arg8",gcc_dwarf_r10,   gcc_dwarf_r10,   LLDB_REGNUM_GENERIC_ARG8, gdb_r10),
173     DEFINE_GPR(r11,      NULL,  gcc_dwarf_r11,   gcc_dwarf_r11,   LLDB_INVALID_REGNUM,    gdb_r11),
174     DEFINE_GPR(r12,      NULL,  gcc_dwarf_r12,   gcc_dwarf_r12,   LLDB_INVALID_REGNUM,    gdb_r12),
175     DEFINE_GPR(r13,      NULL,  gcc_dwarf_r13,   gcc_dwarf_r13,   LLDB_INVALID_REGNUM,    gdb_r13),
176     DEFINE_GPR(r14,      NULL,  gcc_dwarf_r14,   gcc_dwarf_r14,   LLDB_INVALID_REGNUM,    gdb_r14),
177     DEFINE_GPR(r15,      NULL,  gcc_dwarf_r15,   gcc_dwarf_r15,   LLDB_INVALID_REGNUM,    gdb_r15),
178     DEFINE_GPR(r16,      NULL,  gcc_dwarf_r16,   gcc_dwarf_r16,   LLDB_INVALID_REGNUM,    gdb_r16),
179     DEFINE_GPR(r17,      NULL,  gcc_dwarf_r17,   gcc_dwarf_r17,   LLDB_INVALID_REGNUM,    gdb_r17),
180     DEFINE_GPR(r18,      NULL,  gcc_dwarf_r18,   gcc_dwarf_r18,   LLDB_INVALID_REGNUM,    gdb_r18),
181     DEFINE_GPR(r19,      NULL,  gcc_dwarf_r19,   gcc_dwarf_r19,   LLDB_INVALID_REGNUM,    gdb_r19),
182     DEFINE_GPR(r20,      NULL,  gcc_dwarf_r20,   gcc_dwarf_r20,   LLDB_INVALID_REGNUM,    gdb_r20),
183     DEFINE_GPR(r21,      NULL,  gcc_dwarf_r21,   gcc_dwarf_r21,   LLDB_INVALID_REGNUM,    gdb_r21),
184     DEFINE_GPR(r22,      NULL,  gcc_dwarf_r22,   gcc_dwarf_r22,   LLDB_INVALID_REGNUM,    gdb_r22),
185     DEFINE_GPR(r23,      NULL,  gcc_dwarf_r23,   gcc_dwarf_r23,   LLDB_INVALID_REGNUM,    gdb_r23),
186     DEFINE_GPR(r24,      NULL,  gcc_dwarf_r24,   gcc_dwarf_r24,   LLDB_INVALID_REGNUM,    gdb_r24),
187     DEFINE_GPR(r25,      NULL,  gcc_dwarf_r25,   gcc_dwarf_r25,   LLDB_INVALID_REGNUM,    gdb_r25),
188     DEFINE_GPR(r26,      NULL,  gcc_dwarf_r26,   gcc_dwarf_r26,   LLDB_INVALID_REGNUM,    gdb_r26),
189     DEFINE_GPR(r27,      NULL,  gcc_dwarf_r27,   gcc_dwarf_r27,   LLDB_INVALID_REGNUM,    gdb_r27),
190     DEFINE_GPR(r28,      NULL,  gcc_dwarf_r28,   gcc_dwarf_r28,   LLDB_INVALID_REGNUM,    gdb_r28),
191     DEFINE_GPR(r29,      NULL,  gcc_dwarf_r29,   gcc_dwarf_r29,   LLDB_INVALID_REGNUM,    gdb_r29),
192     DEFINE_GPR(r30,      NULL,  gcc_dwarf_r30,   gcc_dwarf_r30,   LLDB_INVALID_REGNUM,    gdb_r30),
193     DEFINE_GPR(r31,      NULL,  gcc_dwarf_r31,   gcc_dwarf_r31,   LLDB_INVALID_REGNUM,    gdb_r31),
194     DEFINE_GPR(lr,       "lr",  gcc_dwarf_lr,    gcc_dwarf_lr,    LLDB_REGNUM_GENERIC_RA, gdb_lr),
195     DEFINE_GPR(cr,       "cr",  gcc_dwarf_cr,    gcc_dwarf_cr,    LLDB_REGNUM_GENERIC_FLAGS, LLDB_INVALID_REGNUM),
196     DEFINE_GPR(xer,      "xer", gcc_dwarf_xer,   gcc_dwarf_xer,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
197     DEFINE_GPR(ctr,      "ctr", gcc_dwarf_ctr,   gcc_dwarf_ctr,   LLDB_INVALID_REGNUM,    LLDB_INVALID_REGNUM),
198     DEFINE_GPR(pc,       "pc",  gcc_dwarf_pc,    gcc_dwarf_pc,    LLDB_REGNUM_GENERIC_PC, LLDB_INVALID_REGNUM),
199     { NULL, NULL, 8, 0, eEncodingUint, eFormatHex, { gcc_dwarf_cfa, gcc_dwarf_cfa, LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM}, NULL, NULL},
200 };
201 
202 static const uint32_t k_num_register_infos = llvm::array_lengthof(g_register_infos);
203 
204 const lldb_private::RegisterInfo *
GetRegisterInfoArray(uint32_t & count)205 ABISysV_ppc64::GetRegisterInfoArray (uint32_t &count)
206 {
207     count = k_num_register_infos;
208     return g_register_infos;
209 }
210 
211 
212 size_t
GetRedZoneSize() const213 ABISysV_ppc64::GetRedZoneSize () const
214 {
215     return 224;
216 }
217 
218 //------------------------------------------------------------------
219 // Static Functions
220 //------------------------------------------------------------------
221 ABISP
CreateInstance(const ArchSpec & arch)222 ABISysV_ppc64::CreateInstance (const ArchSpec &arch)
223 {
224     static ABISP g_abi_sp;
225     if (arch.GetTriple().getArch() == llvm::Triple::ppc64)
226     {
227         if (!g_abi_sp)
228             g_abi_sp.reset (new ABISysV_ppc64);
229         return g_abi_sp;
230     }
231     return ABISP();
232 }
233 
234 bool
PrepareTrivialCall(Thread & thread,addr_t sp,addr_t func_addr,addr_t return_addr,llvm::ArrayRef<addr_t> args) const235 ABISysV_ppc64::PrepareTrivialCall (Thread &thread,
236                                     addr_t sp,
237                                     addr_t func_addr,
238                                     addr_t return_addr,
239                                     llvm::ArrayRef<addr_t> args) const
240 {
241     Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_EXPRESSIONS));
242 
243     if (log)
244     {
245         StreamString s;
246         s.Printf("ABISysV_ppc64::PrepareTrivialCall (tid = 0x%" PRIx64 ", sp = 0x%" PRIx64 ", func_addr = 0x%" PRIx64 ", return_addr = 0x%" PRIx64,
247                     thread.GetID(),
248                     (uint64_t)sp,
249                     (uint64_t)func_addr,
250                     (uint64_t)return_addr);
251 
252         for (size_t i = 0; i < args.size(); ++i)
253             s.Printf (", arg%" PRIu64 " = 0x%" PRIx64, static_cast<uint64_t>(i + 1), args[i]);
254         s.PutCString (")");
255         log->PutCString(s.GetString().c_str());
256     }
257 
258     RegisterContext *reg_ctx = thread.GetRegisterContext().get();
259     if (!reg_ctx)
260         return false;
261 
262     const RegisterInfo *reg_info = NULL;
263 
264     if (args.size() > 8) // TODO handle more than 8 arguments
265         return false;
266 
267     for (size_t i = 0; i < args.size(); ++i)
268     {
269         reg_info = reg_ctx->GetRegisterInfo(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1 + i);
270         if (log)
271             log->Printf("About to write arg%" PRIu64 " (0x%" PRIx64 ") into %s", static_cast<uint64_t>(i + 1), args[i], reg_info->name);
272         if (!reg_ctx->WriteRegisterFromUnsigned(reg_info, args[i]))
273             return false;
274     }
275 
276     // First, align the SP
277 
278     if (log)
279         log->Printf("16-byte aligning SP: 0x%" PRIx64 " to 0x%" PRIx64, (uint64_t)sp, (uint64_t)(sp & ~0xfull));
280 
281     sp &= ~(0xfull); // 16-byte alignment
282 
283     sp -= 8;
284 
285     Error error;
286     const RegisterInfo *pc_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC);
287     const RegisterInfo *sp_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_SP);
288     ProcessSP process_sp (thread.GetProcess());
289 
290     RegisterValue reg_value;
291 
292 #if 0
293     // This code adds an extra frame so that we don't lose the function that we came from
294     // by pushing the PC and the FP and then writing the current FP to point to the FP value
295     // we just pushed. It is disabled for now until the stack backtracing code can be debugged.
296 
297     // Save current PC
298     const RegisterInfo *fp_reg_info = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_FP);
299     if (reg_ctx->ReadRegister(pc_reg_info, reg_value))
300     {
301         if (log)
302             log->Printf("Pushing the current PC onto the stack: 0x%" PRIx64 ": 0x%" PRIx64, (uint64_t)sp, reg_value.GetAsUInt64());
303 
304         if (!process_sp->WritePointerToMemory(sp, reg_value.GetAsUInt64(), error))
305             return false;
306 
307         sp -= 8;
308 
309         // Save current FP
310         if (reg_ctx->ReadRegister(fp_reg_info, reg_value))
311         {
312             if (log)
313                 log->Printf("Pushing the current FP onto the stack: 0x%" PRIx64 ": 0x%" PRIx64, (uint64_t)sp, reg_value.GetAsUInt64());
314 
315             if (!process_sp->WritePointerToMemory(sp, reg_value.GetAsUInt64(), error))
316                 return false;
317         }
318         // Setup FP backchain
319         reg_value.SetUInt64 (sp);
320 
321         if (log)
322             log->Printf("Writing FP:  0x%" PRIx64 " (for FP backchain)", reg_value.GetAsUInt64());
323 
324         if (!reg_ctx->WriteRegister(fp_reg_info, reg_value))
325         {
326             return false;
327         }
328 
329         sp -= 8;
330     }
331 #endif
332 
333     if (log)
334         log->Printf("Pushing the return address onto the stack: 0x%" PRIx64 ": 0x%" PRIx64, (uint64_t)sp, (uint64_t)return_addr);
335 
336     // Save return address onto the stack
337     if (!process_sp->WritePointerToMemory(sp, return_addr, error))
338         return false;
339 
340     // %r1 is set to the actual stack value.
341 
342     if (log)
343         log->Printf("Writing SP: 0x%" PRIx64, (uint64_t)sp);
344 
345     if (!reg_ctx->WriteRegisterFromUnsigned (sp_reg_info, sp))
346         return false;
347 
348     // %pc is set to the address of the called function.
349 
350     if (log)
351         log->Printf("Writing IP: 0x%" PRIx64, (uint64_t)func_addr);
352 
353     if (!reg_ctx->WriteRegisterFromUnsigned (pc_reg_info, func_addr))
354         return false;
355 
356     return true;
357 }
358 
ReadIntegerArgument(Scalar & scalar,unsigned int bit_width,bool is_signed,Thread & thread,uint32_t * argument_register_ids,unsigned int & current_argument_register,addr_t & current_stack_argument)359 static bool ReadIntegerArgument(Scalar           &scalar,
360                                 unsigned int     bit_width,
361                                 bool             is_signed,
362                                 Thread           &thread,
363                                 uint32_t         *argument_register_ids,
364                                 unsigned int     &current_argument_register,
365                                 addr_t           &current_stack_argument)
366 {
367     if (bit_width > 64)
368         return false; // Scalar can't hold large integer arguments
369 
370     if (current_argument_register < 6)
371     {
372         scalar = thread.GetRegisterContext()->ReadRegisterAsUnsigned(argument_register_ids[current_argument_register], 0);
373         current_argument_register++;
374         if (is_signed)
375             scalar.SignExtend (bit_width);
376     }
377     else
378     {
379         uint32_t byte_size = (bit_width + (8-1))/8;
380         Error error;
381         if (thread.GetProcess()->ReadScalarIntegerFromMemory(current_stack_argument, byte_size, is_signed, scalar, error))
382         {
383             current_stack_argument += byte_size;
384             return true;
385         }
386         return false;
387     }
388     return true;
389 }
390 
391 bool
GetArgumentValues(Thread & thread,ValueList & values) const392 ABISysV_ppc64::GetArgumentValues (Thread &thread,
393                                   ValueList &values) const
394 {
395     unsigned int num_values = values.GetSize();
396     unsigned int value_index;
397 
398     // Extract the register context so we can read arguments from registers
399 
400     RegisterContext *reg_ctx = thread.GetRegisterContext().get();
401 
402     if (!reg_ctx)
403         return false;
404 
405     // Get the pointer to the first stack argument so we have a place to start
406     // when reading data
407 
408     addr_t sp = reg_ctx->GetSP(0);
409 
410     if (!sp)
411         return false;
412 
413     addr_t current_stack_argument = sp + 48; // jump over return address
414 
415     uint32_t argument_register_ids[8];
416 
417     argument_register_ids[0] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG1)->kinds[eRegisterKindLLDB];
418     argument_register_ids[1] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG2)->kinds[eRegisterKindLLDB];
419     argument_register_ids[2] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG3)->kinds[eRegisterKindLLDB];
420     argument_register_ids[3] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG4)->kinds[eRegisterKindLLDB];
421     argument_register_ids[4] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG5)->kinds[eRegisterKindLLDB];
422     argument_register_ids[5] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG6)->kinds[eRegisterKindLLDB];
423     argument_register_ids[6] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG7)->kinds[eRegisterKindLLDB];
424     argument_register_ids[7] = reg_ctx->GetRegisterInfo (eRegisterKindGeneric, LLDB_REGNUM_GENERIC_ARG8)->kinds[eRegisterKindLLDB];
425 
426     unsigned int current_argument_register = 0;
427 
428     for (value_index = 0;
429          value_index < num_values;
430          ++value_index)
431     {
432         Value *value = values.GetValueAtIndex(value_index);
433 
434         if (!value)
435             return false;
436 
437         // We currently only support extracting values with Clang QualTypes.
438         // Do we care about others?
439         ClangASTType clang_type = value->GetClangType();
440         if (!clang_type)
441             return false;
442         bool is_signed;
443 
444         if (clang_type.IsIntegerType (is_signed))
445         {
446             ReadIntegerArgument(value->GetScalar(),
447                                 clang_type.GetBitSize(&thread),
448                                 is_signed,
449                                 thread,
450                                 argument_register_ids,
451                                 current_argument_register,
452                                 current_stack_argument);
453         }
454         else if (clang_type.IsPointerType ())
455         {
456             ReadIntegerArgument(value->GetScalar(),
457                                 clang_type.GetBitSize(&thread),
458                                 false,
459                                 thread,
460                                 argument_register_ids,
461                                 current_argument_register,
462                                 current_stack_argument);
463         }
464     }
465 
466     return true;
467 }
468 
469 Error
SetReturnValueObject(lldb::StackFrameSP & frame_sp,lldb::ValueObjectSP & new_value_sp)470 ABISysV_ppc64::SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value_sp)
471 {
472     Error error;
473     if (!new_value_sp)
474     {
475         error.SetErrorString("Empty value object for return value.");
476         return error;
477     }
478 
479     ClangASTType clang_type = new_value_sp->GetClangType();
480     if (!clang_type)
481     {
482         error.SetErrorString ("Null clang type for return value.");
483         return error;
484     }
485 
486     Thread *thread = frame_sp->GetThread().get();
487 
488     bool is_signed;
489     uint32_t count;
490     bool is_complex;
491 
492     RegisterContext *reg_ctx = thread->GetRegisterContext().get();
493 
494     bool set_it_simple = false;
495     if (clang_type.IsIntegerType (is_signed) || clang_type.IsPointerType())
496     {
497         const RegisterInfo *reg_info = reg_ctx->GetRegisterInfoByName("r3", 0);
498 
499         DataExtractor data;
500         Error data_error;
501         size_t num_bytes = new_value_sp->GetData(data, data_error);
502         if (data_error.Fail())
503         {
504             error.SetErrorStringWithFormat("Couldn't convert return value to raw data: %s", data_error.AsCString());
505             return error;
506         }
507         lldb::offset_t offset = 0;
508         if (num_bytes <= 8)
509         {
510             uint64_t raw_value = data.GetMaxU64(&offset, num_bytes);
511 
512             if (reg_ctx->WriteRegisterFromUnsigned (reg_info, raw_value))
513                 set_it_simple = true;
514         }
515         else
516         {
517             error.SetErrorString("We don't support returning longer than 64 bit integer values at present.");
518         }
519 
520     }
521     else if (clang_type.IsFloatingPointType (count, is_complex))
522     {
523         if (is_complex)
524             error.SetErrorString ("We don't support returning complex values at present");
525         else
526         {
527             size_t bit_width = clang_type.GetBitSize(frame_sp.get());
528             if (bit_width <= 64)
529             {
530                 DataExtractor data;
531                 Error data_error;
532                 size_t num_bytes = new_value_sp->GetData(data, data_error);
533                 if (data_error.Fail())
534                 {
535                     error.SetErrorStringWithFormat("Couldn't convert return value to raw data: %s", data_error.AsCString());
536                     return error;
537                 }
538 
539                 unsigned char buffer[16];
540                 ByteOrder byte_order = data.GetByteOrder();
541 
542                 data.CopyByteOrderedData (0, num_bytes, buffer, 16, byte_order);
543                 set_it_simple = true;
544             }
545             else
546             {
547                 // FIXME - don't know how to do 80 bit long doubles yet.
548                 error.SetErrorString ("We don't support returning float values > 64 bits at present");
549             }
550         }
551     }
552 
553     if (!set_it_simple)
554     {
555         // Okay we've got a structure or something that doesn't fit in a simple register.
556         // We should figure out where it really goes, but we don't support this yet.
557         error.SetErrorString ("We only support setting simple integer and float return types at present.");
558     }
559 
560     return error;
561 }
562 
563 
564 ValueObjectSP
GetReturnValueObjectSimple(Thread & thread,ClangASTType & return_clang_type) const565 ABISysV_ppc64::GetReturnValueObjectSimple (Thread &thread,
566                                             ClangASTType &return_clang_type) const
567 {
568     ValueObjectSP return_valobj_sp;
569     Value value;
570 
571     if (!return_clang_type)
572         return return_valobj_sp;
573 
574     //value.SetContext (Value::eContextTypeClangType, return_value_type);
575     value.SetClangType (return_clang_type);
576 
577     RegisterContext *reg_ctx = thread.GetRegisterContext().get();
578     if (!reg_ctx)
579         return return_valobj_sp;
580 
581     const uint32_t type_flags = return_clang_type.GetTypeInfo ();
582     if (type_flags & eTypeIsScalar)
583     {
584         value.SetValueType(Value::eValueTypeScalar);
585 
586         bool success = false;
587         if (type_flags & eTypeIsInteger)
588         {
589             // Extract the register context so we can read arguments from registers
590 
591             const size_t byte_size = return_clang_type.GetByteSize(nullptr);
592             uint64_t raw_value = thread.GetRegisterContext()->ReadRegisterAsUnsigned(reg_ctx->GetRegisterInfoByName("r3", 0), 0);
593             const bool is_signed = (type_flags & eTypeIsSigned) != 0;
594             switch (byte_size)
595             {
596             default:
597                 break;
598 
599             case sizeof(uint64_t):
600                 if (is_signed)
601                     value.GetScalar() = (int64_t)(raw_value);
602                 else
603                     value.GetScalar() = (uint64_t)(raw_value);
604                 success = true;
605                 break;
606 
607             case sizeof(uint32_t):
608                 if (is_signed)
609                     value.GetScalar() = (int32_t)(raw_value & UINT32_MAX);
610                 else
611                     value.GetScalar() = (uint32_t)(raw_value & UINT32_MAX);
612                 success = true;
613                 break;
614 
615             case sizeof(uint16_t):
616                 if (is_signed)
617                     value.GetScalar() = (int16_t)(raw_value & UINT16_MAX);
618                 else
619                     value.GetScalar() = (uint16_t)(raw_value & UINT16_MAX);
620                 success = true;
621                 break;
622 
623             case sizeof(uint8_t):
624                 if (is_signed)
625                     value.GetScalar() = (int8_t)(raw_value & UINT8_MAX);
626                 else
627                     value.GetScalar() = (uint8_t)(raw_value & UINT8_MAX);
628                 success = true;
629                 break;
630             }
631         }
632         else if (type_flags & eTypeIsFloat)
633         {
634             if (type_flags & eTypeIsComplex)
635             {
636                 // Don't handle complex yet.
637             }
638             else
639             {
640                 const size_t byte_size = return_clang_type.GetByteSize(nullptr);
641                 if (byte_size <= sizeof(long double))
642                 {
643                     const RegisterInfo *f1_info = reg_ctx->GetRegisterInfoByName("f1", 0);
644                     RegisterValue f1_value;
645                     if (reg_ctx->ReadRegister (f1_info, f1_value))
646                     {
647                         DataExtractor data;
648                         if (f1_value.GetData(data))
649                         {
650                             lldb::offset_t offset = 0;
651                             if (byte_size == sizeof(float))
652                             {
653                                 value.GetScalar() = (float) data.GetFloat(&offset);
654                                 success = true;
655                             }
656                             else if (byte_size == sizeof(double))
657                             {
658                                 value.GetScalar() = (double) data.GetDouble(&offset);
659                                 success = true;
660                             }
661                         }
662                     }
663                 }
664             }
665         }
666 
667         if (success)
668             return_valobj_sp = ValueObjectConstResult::Create (thread.GetStackFrameAtIndex(0).get(),
669                                                                value,
670                                                                ConstString(""));
671 
672     }
673     else if (type_flags & eTypeIsPointer)
674     {
675         unsigned r3_id = reg_ctx->GetRegisterInfoByName("r3", 0)->kinds[eRegisterKindLLDB];
676         value.GetScalar() = (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r3_id, 0);
677         value.SetValueType(Value::eValueTypeScalar);
678         return_valobj_sp = ValueObjectConstResult::Create (thread.GetStackFrameAtIndex(0).get(),
679                                                            value,
680                                                            ConstString(""));
681     }
682     else if (type_flags & eTypeIsVector)
683     {
684         const size_t byte_size = return_clang_type.GetByteSize(nullptr);
685         if (byte_size > 0)
686         {
687 
688             const RegisterInfo *altivec_reg = reg_ctx->GetRegisterInfoByName("v2", 0);
689             if (altivec_reg)
690             {
691                 if (byte_size <= altivec_reg->byte_size)
692                 {
693                     ProcessSP process_sp (thread.GetProcess());
694                     if (process_sp)
695                     {
696                         std::unique_ptr<DataBufferHeap> heap_data_ap (new DataBufferHeap(byte_size, 0));
697                         const ByteOrder byte_order = process_sp->GetByteOrder();
698                         RegisterValue reg_value;
699                         if (reg_ctx->ReadRegister(altivec_reg, reg_value))
700                         {
701                             Error error;
702                             if (reg_value.GetAsMemoryData (altivec_reg,
703                                                            heap_data_ap->GetBytes(),
704                                                            heap_data_ap->GetByteSize(),
705                                                            byte_order,
706                                                            error))
707                             {
708                                 DataExtractor data (DataBufferSP (heap_data_ap.release()),
709                                                     byte_order,
710                                                     process_sp->GetTarget().GetArchitecture().GetAddressByteSize());
711                                 return_valobj_sp = ValueObjectConstResult::Create (&thread,
712                                                                                    return_clang_type,
713                                                                                    ConstString(""),
714                                                                                    data);
715                             }
716                         }
717                     }
718                 }
719             }
720         }
721     }
722 
723     return return_valobj_sp;
724 }
725 
726 ValueObjectSP
GetReturnValueObjectImpl(Thread & thread,ClangASTType & return_clang_type) const727 ABISysV_ppc64::GetReturnValueObjectImpl (Thread &thread, ClangASTType &return_clang_type) const
728 {
729     ValueObjectSP return_valobj_sp;
730 
731     if (!return_clang_type)
732         return return_valobj_sp;
733 
734     ExecutionContext exe_ctx (thread.shared_from_this());
735     return_valobj_sp = GetReturnValueObjectSimple(thread, return_clang_type);
736     if (return_valobj_sp)
737         return return_valobj_sp;
738 
739     RegisterContextSP reg_ctx_sp = thread.GetRegisterContext();
740     if (!reg_ctx_sp)
741         return return_valobj_sp;
742 
743     const size_t bit_width = return_clang_type.GetBitSize(&thread);
744     if (return_clang_type.IsAggregateType())
745     {
746         Target *target = exe_ctx.GetTargetPtr();
747         bool is_memory = true;
748         if (bit_width <= 128)
749         {
750             ByteOrder target_byte_order = target->GetArchitecture().GetByteOrder();
751             DataBufferSP data_sp (new DataBufferHeap(16, 0));
752             DataExtractor return_ext (data_sp,
753                                       target_byte_order,
754                                       target->GetArchitecture().GetAddressByteSize());
755 
756             const RegisterInfo *r3_info = reg_ctx_sp->GetRegisterInfoByName("r3", 0);
757             const RegisterInfo *rdx_info = reg_ctx_sp->GetRegisterInfoByName("rdx", 0);
758 
759             RegisterValue r3_value, rdx_value;
760             reg_ctx_sp->ReadRegister (r3_info, r3_value);
761             reg_ctx_sp->ReadRegister (rdx_info, rdx_value);
762 
763             DataExtractor r3_data, rdx_data;
764 
765             r3_value.GetData(r3_data);
766             rdx_value.GetData(rdx_data);
767 
768             uint32_t fp_bytes = 0;       // Tracks how much of the xmm registers we've consumed so far
769             uint32_t integer_bytes = 0;  // Tracks how much of the r3/rds registers we've consumed so far
770 
771             const uint32_t num_children = return_clang_type.GetNumFields ();
772 
773             // Since we are in the small struct regime, assume we are not in memory.
774             is_memory = false;
775 
776             for (uint32_t idx = 0; idx < num_children; idx++)
777             {
778                 std::string name;
779                 uint64_t field_bit_offset = 0;
780                 bool is_signed;
781                 bool is_complex;
782                 uint32_t count;
783 
784                 ClangASTType field_clang_type = return_clang_type.GetFieldAtIndex (idx, name, &field_bit_offset, NULL, NULL);
785                 const size_t field_bit_width = field_clang_type.GetBitSize(&thread);
786 
787                 // If there are any unaligned fields, this is stored in memory.
788                 if (field_bit_offset % field_bit_width != 0)
789                 {
790                     is_memory = true;
791                     break;
792                 }
793 
794                 uint32_t field_byte_width = field_bit_width/8;
795                 uint32_t field_byte_offset = field_bit_offset/8;
796 
797 
798                 DataExtractor *copy_from_extractor = NULL;
799                 uint32_t       copy_from_offset    = 0;
800 
801                 if (field_clang_type.IsIntegerType (is_signed) || field_clang_type.IsPointerType ())
802                 {
803                     if (integer_bytes < 8)
804                     {
805                         if (integer_bytes + field_byte_width <= 8)
806                         {
807                             // This is in RAX, copy from register to our result structure:
808                             copy_from_extractor = &r3_data;
809                             copy_from_offset = integer_bytes;
810                             integer_bytes += field_byte_width;
811                         }
812                         else
813                         {
814                             // The next field wouldn't fit in the remaining space, so we pushed it to rdx.
815                             copy_from_extractor = &rdx_data;
816                             copy_from_offset = 0;
817                             integer_bytes = 8 + field_byte_width;
818 
819                         }
820                     }
821                     else if (integer_bytes + field_byte_width <= 16)
822                     {
823                         copy_from_extractor = &rdx_data;
824                         copy_from_offset = integer_bytes - 8;
825                         integer_bytes += field_byte_width;
826                     }
827                     else
828                     {
829                         // The last field didn't fit.  I can't see how that would happen w/o the overall size being
830                         // greater than 16 bytes.  For now, return a NULL return value object.
831                         return return_valobj_sp;
832                     }
833                 }
834                 else if (field_clang_type.IsFloatingPointType (count, is_complex))
835                 {
836                     // Structs with long doubles are always passed in memory.
837                     if (field_bit_width == 128)
838                     {
839                         is_memory = true;
840                         break;
841                     }
842                     else if (field_bit_width == 64)
843                     {
844                         copy_from_offset = 0;
845                         fp_bytes += field_byte_width;
846                     }
847                     else if (field_bit_width == 32)
848                     {
849                         // This one is kind of complicated.  If we are in an "eightbyte" with another float, we'll
850                         // be stuffed into an xmm register with it.  If we are in an "eightbyte" with one or more ints,
851                         // then we will be stuffed into the appropriate GPR with them.
852                         bool in_gpr;
853                         if (field_byte_offset % 8 == 0)
854                         {
855                             // We are at the beginning of one of the eightbytes, so check the next element (if any)
856                             if (idx == num_children - 1)
857                                 in_gpr = false;
858                             else
859                             {
860                                 uint64_t next_field_bit_offset = 0;
861                                 ClangASTType next_field_clang_type = return_clang_type.GetFieldAtIndex (idx + 1,
862                                                                                                         name,
863                                                                                                         &next_field_bit_offset,
864                                                                                                         NULL,
865                                                                                                         NULL);
866                                 if (next_field_clang_type.IsIntegerType (is_signed))
867                                     in_gpr = true;
868                                 else
869                                 {
870                                     copy_from_offset = 0;
871                                     in_gpr = false;
872                                 }
873                             }
874 
875                         }
876                         else if (field_byte_offset % 4 == 0)
877                         {
878                             // We are inside of an eightbyte, so see if the field before us is floating point:
879                             // This could happen if somebody put padding in the structure.
880                             if (idx == 0)
881                                 in_gpr = false;
882                             else
883                             {
884                                 uint64_t prev_field_bit_offset = 0;
885                                 ClangASTType prev_field_clang_type = return_clang_type.GetFieldAtIndex (idx - 1,
886                                                                                                         name,
887                                                                                                         &prev_field_bit_offset,
888                                                                                                         NULL,
889                                                                                                         NULL);
890                                 if (prev_field_clang_type.IsIntegerType (is_signed))
891                                     in_gpr = true;
892                                 else
893                                 {
894                                     copy_from_offset = 4;
895                                     in_gpr = false;
896                                 }
897                             }
898 
899                         }
900                         else
901                         {
902                             is_memory = true;
903                             continue;
904                         }
905 
906                         // Okay, we've figured out whether we are in GPR or XMM, now figure out which one.
907                         if (in_gpr)
908                         {
909                             if (integer_bytes < 8)
910                             {
911                                 // This is in RAX, copy from register to our result structure:
912                                 copy_from_extractor = &r3_data;
913                                 copy_from_offset = integer_bytes;
914                                 integer_bytes += field_byte_width;
915                             }
916                             else
917                             {
918                                 copy_from_extractor = &rdx_data;
919                                 copy_from_offset = integer_bytes - 8;
920                                 integer_bytes += field_byte_width;
921                             }
922                         }
923                         else
924                         {
925                             fp_bytes += field_byte_width;
926                         }
927                     }
928                 }
929 
930                 // These two tests are just sanity checks.  If I somehow get the
931                 // type calculation wrong above it is better to just return nothing
932                 // than to assert or crash.
933                 if (!copy_from_extractor)
934                     return return_valobj_sp;
935                 if (copy_from_offset + field_byte_width > copy_from_extractor->GetByteSize())
936                     return return_valobj_sp;
937 
938                 copy_from_extractor->CopyByteOrderedData (copy_from_offset,
939                                                           field_byte_width,
940                                                           data_sp->GetBytes() + field_byte_offset,
941                                                           field_byte_width,
942                                                           target_byte_order);
943             }
944 
945             if (!is_memory)
946             {
947                 // The result is in our data buffer.  Let's make a variable object out of it:
948                 return_valobj_sp = ValueObjectConstResult::Create (&thread,
949                                                                    return_clang_type,
950                                                                    ConstString(""),
951                                                                    return_ext);
952             }
953         }
954 
955 
956         // FIXME: This is just taking a guess, r3 may very well no longer hold the return storage location.
957         // If we are going to do this right, when we make a new frame we should check to see if it uses a memory
958         // return, and if we are at the first instruction and if so stash away the return location.  Then we would
959         // only return the memory return value if we know it is valid.
960 
961         if (is_memory)
962         {
963             unsigned r3_id = reg_ctx_sp->GetRegisterInfoByName("r3", 0)->kinds[eRegisterKindLLDB];
964             lldb::addr_t storage_addr = (uint64_t)thread.GetRegisterContext()->ReadRegisterAsUnsigned(r3_id, 0);
965             return_valobj_sp = ValueObjectMemory::Create (&thread,
966                                                           "",
967                                                           Address (storage_addr, NULL),
968                                                           return_clang_type);
969         }
970     }
971 
972     return return_valobj_sp;
973 }
974 
975 bool
CreateFunctionEntryUnwindPlan(UnwindPlan & unwind_plan)976 ABISysV_ppc64::CreateFunctionEntryUnwindPlan (UnwindPlan &unwind_plan)
977 {
978     unwind_plan.Clear();
979     unwind_plan.SetRegisterKind (eRegisterKindDWARF);
980 
981     uint32_t lr_reg_num = gcc_dwarf_lr;
982     uint32_t sp_reg_num = gcc_dwarf_r1;
983     uint32_t pc_reg_num = gcc_dwarf_pc;
984 
985     UnwindPlan::RowSP row(new UnwindPlan::Row);
986 
987     // Our Call Frame Address is the stack pointer value
988     row->GetCFAValue().SetIsRegisterPlusOffset(sp_reg_num, 0);
989 
990     // The previous PC is in the LR
991     row->SetRegisterLocationToRegister(pc_reg_num, lr_reg_num, true);
992     unwind_plan.AppendRow (row);
993 
994     // All other registers are the same.
995 
996     unwind_plan.SetSourceName ("ppc64 at-func-entry default");
997     unwind_plan.SetSourcedFromCompiler (eLazyBoolNo);
998 
999     return true;
1000 }
1001 
1002 bool
CreateDefaultUnwindPlan(UnwindPlan & unwind_plan)1003 ABISysV_ppc64::CreateDefaultUnwindPlan (UnwindPlan &unwind_plan)
1004 {
1005     unwind_plan.Clear();
1006     unwind_plan.SetRegisterKind (eRegisterKindDWARF);
1007 
1008     uint32_t sp_reg_num = gcc_dwarf_r1;
1009     uint32_t pc_reg_num = gcc_dwarf_lr;
1010 
1011     UnwindPlan::RowSP row(new UnwindPlan::Row);
1012 
1013     const int32_t ptr_size = 8;
1014     row->GetCFAValue().SetIsRegisterDereferenced(sp_reg_num);
1015 
1016     row->SetRegisterLocationToAtCFAPlusOffset(pc_reg_num, ptr_size * 2, true);
1017     row->SetRegisterLocationToIsCFAPlusOffset(sp_reg_num, 0, true);
1018     row->SetRegisterLocationToAtCFAPlusOffset(gcc_dwarf_cr, ptr_size, true);
1019 
1020     unwind_plan.AppendRow (row);
1021     unwind_plan.SetSourceName ("ppc64 default unwind plan");
1022     unwind_plan.SetSourcedFromCompiler (eLazyBoolNo);
1023     unwind_plan.SetUnwindPlanValidAtAllInstructions (eLazyBoolNo);
1024     unwind_plan.SetReturnAddressRegister(gcc_dwarf_lr);
1025     return true;
1026 }
1027 
1028 bool
RegisterIsVolatile(const RegisterInfo * reg_info)1029 ABISysV_ppc64::RegisterIsVolatile (const RegisterInfo *reg_info)
1030 {
1031     return !RegisterIsCalleeSaved (reg_info);
1032 }
1033 
1034 
1035 
1036 // See "Register Usage" in the
1037 // "System V Application Binary Interface"
1038 // "64-bit PowerPC ELF Application Binary Interface Supplement"
1039 // current version is 1.9 released 2004 at http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi-1.9.pdf
1040 
1041 bool
RegisterIsCalleeSaved(const RegisterInfo * reg_info)1042 ABISysV_ppc64::RegisterIsCalleeSaved (const RegisterInfo *reg_info)
1043 {
1044     if (reg_info)
1045     {
1046         // Preserved registers are :
1047         //    r1,r2,r13-r31
1048         //    cr2-cr4 (partially preserved)
1049         //    f14-f31 (not yet)
1050         //    v20-v31 (not yet)
1051         //    vrsave (not yet)
1052 
1053         const char *name = reg_info->name;
1054         if (name[0] == 'r')
1055         {
1056             if ((name[1] == '1' || name[1] == '2') && name[2] == '\0')
1057                 return true;
1058             if (name[1] == '1' && name[2] > '2')
1059                 return true;
1060             if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1061                 return true;
1062         }
1063 
1064         if (name[0] == 'f' && name[1] >= '0' && name[2] <= '9')
1065         {
1066             if (name[2] == '\0')
1067                 return false;
1068             if (name[1] == '1' && name[2] >= '4')
1069                 return true;
1070             if ((name[1] == '2' || name[1] == '3') && name[2] != '\0')
1071                 return true;
1072         }
1073 
1074         if (name[0] == 's' && name[1] == 'p' && name[2] == '\0')   // sp
1075             return true;
1076         if (name[0] == 'f' && name[1] == 'p' && name[2] == '\0')   // fp
1077             return true;
1078         if (name[0] == 'p' && name[1] == 'c' && name[2] == '\0')   // pc
1079             return true;
1080     }
1081     return false;
1082 }
1083 
1084 
1085 
1086 void
Initialize()1087 ABISysV_ppc64::Initialize()
1088 {
1089     PluginManager::RegisterPlugin (GetPluginNameStatic(),
1090                                    "System V ABI for ppc64 targets",
1091                                    CreateInstance);
1092 }
1093 
1094 void
Terminate()1095 ABISysV_ppc64::Terminate()
1096 {
1097     PluginManager::UnregisterPlugin (CreateInstance);
1098 }
1099 
1100 lldb_private::ConstString
GetPluginNameStatic()1101 ABISysV_ppc64::GetPluginNameStatic()
1102 {
1103     static ConstString g_name("sysv-ppc64");
1104     return g_name;
1105 }
1106 
1107 //------------------------------------------------------------------
1108 // PluginInterface protocol
1109 //------------------------------------------------------------------
1110 lldb_private::ConstString
GetPluginName()1111 ABISysV_ppc64::GetPluginName()
1112 {
1113     return GetPluginNameStatic();
1114 }
1115 
1116 uint32_t
GetPluginVersion()1117 ABISysV_ppc64::GetPluginVersion()
1118 {
1119     return 1;
1120 }
1121 
1122