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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
//===- MipsJITInfo.cpp - Implement the JIT interfaces for the Mips target -===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the JIT interfaces for the Mips target.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "jit"
#include "MipsJITInfo.h"
#include "MipsInstrInfo.h"
#include "MipsRelocations.h"
#include "MipsSubtarget.h"
#include "llvm/Function.h"
#include "llvm/CodeGen/JITCodeEmitter.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Memory.h"
#include <cstdlib>
using namespace llvm;
void MipsJITInfo::replaceMachineCodeForFunction(void *Old, void *New) {
report_fatal_error("MipsJITInfo::replaceMachineCodeForFunction");
}
/// JITCompilerFunction - This contains the address of the JIT function used to
/// compile a function lazily.
static TargetJITInfo::JITCompilerFn JITCompilerFunction;
// Get the ASMPREFIX for the current host. This is often '_'.
#ifndef __USER_LABEL_PREFIX__
#define __USER_LABEL_PREFIX__
#endif
#define GETASMPREFIX2(X) #X
#define GETASMPREFIX(X) GETASMPREFIX2(X)
#define ASMPREFIX GETASMPREFIX(__USER_LABEL_PREFIX__)
// save registers, call MipsCompilationCallbackC, restore registers
extern "C" {
#if defined (__mips__)
void MipsCompilationCallback();
asm(
".text\n"
".align 2\n"
".globl " ASMPREFIX "MipsCompilationCallback\n"
ASMPREFIX "MipsCompilationCallback:\n"
".ent " ASMPREFIX "MipsCompilationCallback\n"
".set noreorder\n"
".cpload $t9\n"
".frame $29, 32, $31\n"
"addiu $sp, $sp, -40\n"
"sw $a0, 4($sp)\n"
"sw $a1, 8($sp)\n"
"sw $a2, 12($sp)\n"
"sw $a3, 20($sp)\n"
"sw $ra, 24($sp)\n"
"sw $v0, 28($sp)\n"
"sw $v1, 32($sp)\n"
"sw $t8, 36($sp)\n"
".cprestore 16\n"
"addiu $a0, $t8, -16\n"
"jal " ASMPREFIX "MipsCompilationCallbackC\n"
"nop\n"
"lw $a0, 4($sp)\n"
"lw $a1, 8($sp)\n"
"lw $a2, 12($sp)\n"
"lw $a3, 20($sp)\n"
"lw $ra, 24($sp)\n"
"lw $v0, 28($sp)\n"
"lw $v1, 32($sp)\n"
"lw $t8, 36($sp)\n"
"addiu $sp, $sp, 40\n"
"addiu $t8, $t8, -16\n"
"jr $t8\n"
"nop\n"
".set reorder\n"
".end " ASMPREFIX "MipsCompilationCallback\n"
);
#else // host != Mips
void MipsCompilationCallback() {
llvm_unreachable(
"Cannot call MipsCompilationCallback() on a non-Mips arch!");
}
#endif
}
/// MipsCompilationCallbackC - This is the target-specific function invoked
/// by the function stub when we did not know the real target of a call.
/// This function must locate the start of the stub or call site and pass
/// it into the JIT compiler function.
extern "C" void MipsCompilationCallbackC(intptr_t StubAddr) {
// Get the address of the compiled code for this function.
intptr_t NewVal = (intptr_t) JITCompilerFunction((void*) StubAddr);
*(intptr_t *) (StubAddr) = 2 << 26 | ((NewVal & 0x0fffffff) >> 2); // J NewVal
*(intptr_t *) (StubAddr + 4) = 0; // NOP
*(intptr_t *) (StubAddr + 8) = 0; // NOP
*(intptr_t *) (StubAddr + 12) = 0; // NOP
sys::Memory::InvalidateInstructionCache((void*) StubAddr, 16);
}
TargetJITInfo::LazyResolverFn MipsJITInfo::getLazyResolverFunction(
JITCompilerFn F) {
JITCompilerFunction = F;
return MipsCompilationCallback;
}
TargetJITInfo::StubLayout MipsJITInfo::getStubLayout() {
StubLayout Result = { 24, 4 }; // {Size. Alignment} (of FunctionStub)
return Result;
}
void *MipsJITInfo::emitFunctionStub(const Function* F, void *Fn,
JITCodeEmitter &JCE) {
JCE.emitAlignment(4);
void *Addr = (void*) (JCE.getCurrentPCValue());
unsigned arg0 = ((intptr_t) MipsCompilationCallback >> 16);
if ((((intptr_t) MipsCompilationCallback & 0xffff) >> 15) == 1) {
arg0 += 1; // same hack as in relocate()
}
// LUI t9, %hi(MipsCompilationCallback)
JCE.emitWordLE(0xf << 26 | 25 << 16 | arg0);
// ADDiu t9, t9, %lo(MipsCompilationCallback)
JCE.emitWordLE(9 << 26 | 25 << 21 | 25 << 16
| ((intptr_t) MipsCompilationCallback & 0xffff));
// JALR t8, t9
JCE.emitWordLE(25 << 21 | 24 << 11 | 9);
JCE.emitWordLE(0); // NOP
sys::Memory::InvalidateInstructionCache((void*) Addr, 16);
return Addr;
}
/// relocate - Before the JIT can run a block of code that has been emitted,
/// it must rewrite the code to contain the actual addresses of any
/// referenced global symbols.
void MipsJITInfo::relocate(void *Function, MachineRelocation *MR,
unsigned NumRelocs, unsigned char* GOTBase) {
for (unsigned i = 0; i != NumRelocs; ++i, ++MR) {
void *RelocPos = (char*) Function + MR->getMachineCodeOffset();
intptr_t ResultPtr = (intptr_t) MR->getResultPointer();
switch ((Mips::RelocationType) MR->getRelocationType()) {
case Mips::reloc_mips_pcrel:
ResultPtr = (((ResultPtr - (intptr_t) RelocPos) - 4) >> 2) & 0xffff;
*((unsigned*) RelocPos) |= (unsigned) ResultPtr;
break;
case Mips::reloc_mips_j_jal: {
ResultPtr = (ResultPtr & 0x0fffffff) >> 2;
*((unsigned*) RelocPos) |= (unsigned) ResultPtr;
}
break;
case Mips::reloc_mips_hi: {
ResultPtr = ResultPtr >> 16;
// see See MIPS Run Linux, chapter 9.4
if ((((intptr_t) (MR->getResultPointer()) & 0xffff) >> 15) == 1) {
ResultPtr += 1;
}
*((unsigned*) RelocPos) |= (unsigned) ResultPtr;
}
break;
case Mips::reloc_mips_lo:
ResultPtr = ResultPtr & 0xffff;
*((unsigned*) RelocPos) |= (unsigned) ResultPtr;
break;
default:
assert(0 && "MipsJITInfo.unknown relocation;");
}
}
}
|
