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
|
// Copyright 2014 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#if V8_TARGET_ARCH_PPC
#include "src/debug/debug.h"
#include "src/codegen.h"
#include "src/debug/liveedit.h"
namespace v8 {
namespace internal {
#define __ ACCESS_MASM(masm)
void EmitDebugBreakSlot(MacroAssembler* masm) {
Label check_size;
__ bind(&check_size);
for (int i = 0; i < Assembler::kDebugBreakSlotInstructions; i++) {
__ nop(MacroAssembler::DEBUG_BREAK_NOP);
}
DCHECK_EQ(Assembler::kDebugBreakSlotInstructions,
masm->InstructionsGeneratedSince(&check_size));
}
void DebugCodegen::GenerateSlot(MacroAssembler* masm, RelocInfo::Mode mode) {
// Generate enough nop's to make space for a call instruction. Avoid emitting
// the trampoline pool in the debug break slot code.
Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm);
masm->RecordDebugBreakSlot(mode);
EmitDebugBreakSlot(masm);
}
void DebugCodegen::ClearDebugBreakSlot(Isolate* isolate, Address pc) {
CodePatcher patcher(isolate, pc, Assembler::kDebugBreakSlotInstructions);
EmitDebugBreakSlot(patcher.masm());
}
void DebugCodegen::PatchDebugBreakSlot(Isolate* isolate, Address pc,
Handle<Code> code) {
DCHECK(code->is_debug_stub());
CodePatcher patcher(isolate, pc, Assembler::kDebugBreakSlotInstructions);
// Patch the code changing the debug break slot code from
//
// ori r3, r3, 0
// ori r3, r3, 0
// ori r3, r3, 0
// ori r3, r3, 0
// ori r3, r3, 0
//
// to a call to the debug break code, using a FIXED_SEQUENCE.
//
// mov r0, <address>
// mtlr r0
// blrl
//
Assembler::BlockTrampolinePoolScope block_trampoline_pool(patcher.masm());
patcher.masm()->mov(v8::internal::r0,
Operand(reinterpret_cast<intptr_t>(code->entry())));
patcher.masm()->mtctr(v8::internal::r0);
patcher.masm()->bctrl();
}
bool DebugCodegen::DebugBreakSlotIsPatched(Address pc) {
Instr current_instr = Assembler::instr_at(pc);
return !Assembler::IsNop(current_instr, Assembler::DEBUG_BREAK_NOP);
}
void DebugCodegen::GenerateDebugBreakStub(MacroAssembler* masm,
DebugBreakCallHelperMode mode) {
__ RecordComment("Debug break");
{
FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
// Load padding words on stack.
__ LoadSmiLiteral(ip, Smi::FromInt(LiveEdit::kFramePaddingValue));
for (int i = 0; i < LiveEdit::kFramePaddingInitialSize; i++) {
__ push(ip);
}
__ LoadSmiLiteral(ip, Smi::FromInt(LiveEdit::kFramePaddingInitialSize));
__ push(ip);
// Push arguments for DebugBreak call.
if (mode == SAVE_RESULT_REGISTER) {
// Break on return.
__ push(r3);
} else {
// Non-return breaks.
__ Push(masm->isolate()->factory()->the_hole_value());
}
__ mov(r3, Operand(1));
__ mov(r4,
Operand(ExternalReference(
Runtime::FunctionForId(Runtime::kDebugBreak), masm->isolate())));
CEntryStub ceb(masm->isolate(), 1);
__ CallStub(&ceb);
if (FLAG_debug_code) {
for (int i = 0; i < kNumJSCallerSaved; i++) {
Register reg = {JSCallerSavedCode(i)};
// Do not clobber r3 if mode is SAVE_RESULT_REGISTER. It will
// contain return value of the function.
if (!(reg.is(r3) && (mode == SAVE_RESULT_REGISTER))) {
__ mov(reg, Operand(kDebugZapValue));
}
}
}
// Don't bother removing padding bytes pushed on the stack
// as the frame is going to be restored right away.
// Leave the internal frame.
}
// Now that the break point has been handled, resume normal execution by
// jumping to the target address intended by the caller and that was
// overwritten by the address of DebugBreakXXX.
ExternalReference after_break_target =
ExternalReference::debug_after_break_target_address(masm->isolate());
__ mov(ip, Operand(after_break_target));
__ LoadP(ip, MemOperand(ip));
__ JumpToJSEntry(ip);
}
void DebugCodegen::GenerateFrameDropperLiveEdit(MacroAssembler* masm) {
// Load the function pointer off of our current stack frame.
__ LoadP(r4, MemOperand(fp, FrameDropperFrameConstants::kFunctionOffset));
// Pop return address and frame
__ LeaveFrame(StackFrame::INTERNAL);
ParameterCount dummy(0);
__ CheckDebugHook(r4, no_reg, dummy, dummy);
// Load context from the function.
__ LoadP(cp, FieldMemOperand(r4, JSFunction::kContextOffset));
// Clear new.target as a safety measure.
__ LoadRoot(r6, Heap::kUndefinedValueRootIndex);
// Get function code.
__ LoadP(ip, FieldMemOperand(r4, JSFunction::kSharedFunctionInfoOffset));
__ LoadP(ip, FieldMemOperand(ip, SharedFunctionInfo::kCodeOffset));
__ addi(ip, ip, Operand(Code::kHeaderSize - kHeapObjectTag));
// Re-run JSFunction, r4 is function, cp is context.
__ Jump(ip);
}
const bool LiveEdit::kFrameDropperSupported = true;
#undef __
} // namespace internal
} // namespace v8
#endif // V8_TARGET_ARCH_PPC
|
