1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
//===------- OrcTargetSupport.cpp - Target support utilities for Orc ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "llvm/ADT/Triple.h"
#include "llvm/ExecutionEngine/Orc/OrcTargetSupport.h"
#include "llvm/Support/Process.h"
#include <array>
namespace llvm {
namespace orc {
void OrcX86_64::writeResolverCode(uint8_t *ResolverMem, JITReentryFn ReentryFn,
void *CallbackMgr) {
const uint8_t ResolverCode[] = {
// resolver_entry:
0x55, // 0x00: pushq %rbp
0x48, 0x89, 0xe5, // 0x01: movq %rsp, %rbp
0x50, // 0x04: pushq %rax
0x53, // 0x05: pushq %rbx
0x51, // 0x06: pushq %rcx
0x52, // 0x07: pushq %rdx
0x56, // 0x08: pushq %rsi
0x57, // 0x09: pushq %rdi
0x41, 0x50, // 0x0a: pushq %r8
0x41, 0x51, // 0x0c: pushq %r9
0x41, 0x52, // 0x0e: pushq %r10
0x41, 0x53, // 0x10: pushq %r11
0x41, 0x54, // 0x12: pushq %r12
0x41, 0x55, // 0x14: pushq %r13
0x41, 0x56, // 0x16: pushq %r14
0x41, 0x57, // 0x18: pushq %r15
0x48, 0x81, 0xec, 0x08, 0x02, 0x00, 0x00, // 0x1a: subq 20, %rsp
0x48, 0x0f, 0xae, 0x04, 0x24, // 0x21: fxsave64 (%rsp)
0x48, 0x8d, 0x3d, 0x43, 0x00, 0x00, 0x00, // 0x26: leaq 67(%rip), %rdi
0x48, 0x8b, 0x3f, // 0x2d: movq (%rdi), %rdi
0x48, 0x8b, 0x75, 0x08, // 0x30: movq 8(%rbp), %rsi
0x48, 0x83, 0xee, 0x06, // 0x34: subq $6, %rsi
0x48, 0xb8, // 0x38: movabsq $0, %rax
// 0x3a: JIT re-entry fn addr:
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0xff, 0xd0, // 0x42: callq *%rax
0x48, 0x89, 0x45, 0x08, // 0x44: movq %rax, 8(%rbp)
0x48, 0x0f, 0xae, 0x0c, 0x24, // 0x48: fxrstor64 (%rsp)
0x48, 0x81, 0xc4, 0x08, 0x02, 0x00, 0x00, // 0x4d: addq 20, %rsp
0x41, 0x5f, // 0x54: popq %r15
0x41, 0x5e, // 0x56: popq %r14
0x41, 0x5d, // 0x58: popq %r13
0x41, 0x5c, // 0x5a: popq %r12
0x41, 0x5b, // 0x5c: popq %r11
0x41, 0x5a, // 0x5e: popq %r10
0x41, 0x59, // 0x60: popq %r9
0x41, 0x58, // 0x62: popq %r8
0x5f, // 0x64: popq %rdi
0x5e, // 0x65: popq %rsi
0x5a, // 0x66: popq %rdx
0x59, // 0x67: popq %rcx
0x5b, // 0x68: popq %rbx
0x58, // 0x69: popq %rax
0x5d, // 0x6a: popq %rbp
0xc3, // 0x6b: retq
0x00, 0x00, 0x00, 0x00, // 0x6c: <padding>
// 0x70: Callback mgr address.
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
};
const unsigned ReentryFnAddrOffset = 0x3a;
const unsigned CallbackMgrAddrOffset = 0x70;
memcpy(ResolverMem, ResolverCode, sizeof(ResolverCode));
memcpy(ResolverMem + ReentryFnAddrOffset, &ReentryFn, sizeof(ReentryFn));
memcpy(ResolverMem + CallbackMgrAddrOffset, &CallbackMgr,
sizeof(CallbackMgr));
}
void OrcX86_64::writeTrampolines(uint8_t *TrampolineMem, void *ResolverAddr,
unsigned NumTrampolines) {
unsigned OffsetToPtr = NumTrampolines * TrampolineSize;
memcpy(TrampolineMem + OffsetToPtr, &ResolverAddr, sizeof(void*));
uint64_t *Trampolines = reinterpret_cast<uint64_t*>(TrampolineMem);
uint64_t CallIndirPCRel = 0xf1c40000000015ff;
for (unsigned I = 0; I < NumTrampolines; ++I, OffsetToPtr -= TrampolineSize)
Trampolines[I] = CallIndirPCRel | ((OffsetToPtr - 6) << 16);
}
std::error_code OrcX86_64::emitIndirectStubsBlock(IndirectStubsInfo &StubsInfo,
unsigned MinStubs,
void *InitialPtrVal) {
// Stub format is:
//
// .section __orc_stubs
// stub1:
// jmpq *ptr1(%rip)
// .byte 0xC4 ; <- Invalid opcode padding.
// .byte 0xF1
// stub2:
// jmpq *ptr2(%rip)
//
// ...
//
// .section __orc_ptrs
// ptr1:
// .quad 0x0
// ptr2:
// .quad 0x0
//
// ...
const unsigned StubSize = IndirectStubsInfo::StubSize;
// Emit at least MinStubs, rounded up to fill the pages allocated.
unsigned PageSize = sys::Process::getPageSize();
unsigned NumPages = ((MinStubs * StubSize) + (PageSize - 1)) / PageSize;
unsigned NumStubs = (NumPages * PageSize) / StubSize;
// Allocate memory for stubs and pointers in one call.
std::error_code EC;
auto StubsMem =
sys::OwningMemoryBlock(
sys::Memory::allocateMappedMemory(2 * NumPages * PageSize, nullptr,
sys::Memory::MF_READ |
sys::Memory::MF_WRITE,
EC));
if (EC)
return EC;
// Create separate MemoryBlocks representing the stubs and pointers.
sys::MemoryBlock StubsBlock(StubsMem.base(), NumPages * PageSize);
sys::MemoryBlock PtrsBlock(static_cast<char*>(StubsMem.base()) +
NumPages * PageSize,
NumPages * PageSize);
// Populate the stubs page stubs and mark it executable.
uint64_t *Stub = reinterpret_cast<uint64_t*>(StubsBlock.base());
uint64_t PtrOffsetField =
static_cast<uint64_t>(NumPages * PageSize - 6) << 16;
for (unsigned I = 0; I < NumStubs; ++I)
Stub[I] = 0xF1C40000000025ff | PtrOffsetField;
if (auto EC = sys::Memory::protectMappedMemory(StubsBlock,
sys::Memory::MF_READ |
sys::Memory::MF_EXEC))
return EC;
// Initialize all pointers to point at FailureAddress.
void **Ptr = reinterpret_cast<void**>(PtrsBlock.base());
for (unsigned I = 0; I < NumStubs; ++I)
Ptr[I] = InitialPtrVal;
StubsInfo.NumStubs = NumStubs;
StubsInfo.StubsMem = std::move(StubsMem);
return std::error_code();
}
} // End namespace orc.
} // End namespace llvm.
|
