1 // Copyright 2012 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
9 #if V8_TARGET_ARCH_MIPS64
11 #include "src/codegen.h"
12 #include "src/debug.h"
17 void BreakLocation::SetDebugBreakAtReturn() {
18 // Mips return sequence:
25 // nop (in branch delay slot)
27 // Make sure this constant matches the number if instructions we emit.
28 DCHECK(Assembler::kJSReturnSequenceInstructions == 7);
29 CodePatcher patcher(pc(), Assembler::kJSReturnSequenceInstructions);
30 // li and Call pseudo-instructions emit 6 + 2 instructions.
31 patcher.masm()->li(v8::internal::t9, Operand(reinterpret_cast<int64_t>(
32 debug_info_->GetIsolate()->builtins()->Return_DebugBreak()->entry())),
34 patcher.masm()->Call(v8::internal::t9);
35 // Place nop to match return sequence size.
36 patcher.masm()->nop();
37 // TODO(mips): Open issue about using breakpoint instruction instead of nops.
38 // patcher.masm()->bkpt(0);
42 void BreakLocation::SetDebugBreakAtSlot() {
43 DCHECK(IsDebugBreakSlot());
44 // Patch the code changing the debug break slot code from:
45 // nop(DEBUG_BREAK_NOP) - nop(1) is sll(zero_reg, zero_reg, 1)
46 // nop(DEBUG_BREAK_NOP)
47 // nop(DEBUG_BREAK_NOP)
48 // nop(DEBUG_BREAK_NOP)
49 // nop(DEBUG_BREAK_NOP)
50 // nop(DEBUG_BREAK_NOP)
51 // to a call to the debug break slot code.
52 // li t9, address (4-instruction sequence on mips64)
53 // call t9 (jalr t9 / nop instruction pair)
54 CodePatcher patcher(pc(), Assembler::kDebugBreakSlotInstructions);
55 patcher.masm()->li(v8::internal::t9,
56 Operand(reinterpret_cast<int64_t>(
57 debug_info_->GetIsolate()->builtins()->Slot_DebugBreak()->entry())),
59 patcher.masm()->Call(v8::internal::t9);
63 #define __ ACCESS_MASM(masm)
67 static void Generate_DebugBreakCallHelper(MacroAssembler* masm,
69 RegList non_object_regs) {
71 FrameScope scope(masm, StackFrame::INTERNAL);
73 // Load padding words on stack.
74 __ li(at, Operand(Smi::FromInt(LiveEdit::kFramePaddingValue)));
76 Operand(kPointerSize * LiveEdit::kFramePaddingInitialSize));
77 for (int i = LiveEdit::kFramePaddingInitialSize - 1; i >= 0; i--) {
78 __ sd(at, MemOperand(sp, kPointerSize * i));
80 __ li(at, Operand(Smi::FromInt(LiveEdit::kFramePaddingInitialSize)));
84 // TODO(plind): This needs to be revised to store pairs of smi's per
85 // the other 64-bit arch's.
87 // Store the registers containing live values on the expression stack to
88 // make sure that these are correctly updated during GC. Non object values
89 // are stored as a smi causing it to be untouched by GC.
90 DCHECK((object_regs & ~kJSCallerSaved) == 0);
91 DCHECK((non_object_regs & ~kJSCallerSaved) == 0);
92 DCHECK((object_regs & non_object_regs) == 0);
93 for (int i = 0; i < kNumJSCallerSaved; i++) {
94 int r = JSCallerSavedCode(i);
96 if ((object_regs & (1 << r)) != 0) {
99 if ((non_object_regs & (1 << r)) != 0) {
100 __ PushRegisterAsTwoSmis(reg);
105 __ RecordComment("// Calling from debug break to runtime - come in - over");
107 __ PrepareCEntryArgs(0); // No arguments.
108 __ PrepareCEntryFunction(ExternalReference::debug_break(masm->isolate()));
110 CEntryStub ceb(masm->isolate(), 1);
113 // Restore the register values from the expression stack.
114 for (int i = kNumJSCallerSaved - 1; i >= 0; i--) {
115 int r = JSCallerSavedCode(i);
116 Register reg = { r };
117 if ((non_object_regs & (1 << r)) != 0) {
118 __ PopRegisterAsTwoSmis(reg, at);
120 if ((object_regs & (1 << r)) != 0) {
123 if (FLAG_debug_code &&
124 (((object_regs |non_object_regs) & (1 << r)) == 0)) {
125 __ li(reg, kDebugZapValue);
129 // Don't bother removing padding bytes pushed on the stack
130 // as the frame is going to be restored right away.
132 // Leave the internal frame.
135 // Now that the break point has been handled, resume normal execution by
136 // jumping to the target address intended by the caller and that was
137 // overwritten by the address of DebugBreakXXX.
138 ExternalReference after_break_target =
139 ExternalReference::debug_after_break_target_address(masm->isolate());
140 __ li(t9, Operand(after_break_target));
141 __ ld(t9, MemOperand(t9));
146 void DebugCodegen::GenerateCallICStubDebugBreak(MacroAssembler* masm) {
147 // Register state for CallICStub
148 // ----------- S t a t e -------------
150 // -- a3 : slot in feedback array (smi)
151 // -----------------------------------
152 Generate_DebugBreakCallHelper(masm, a1.bit() | a3.bit(), 0);
156 void DebugCodegen::GenerateLoadICDebugBreak(MacroAssembler* masm) {
157 Register receiver = LoadDescriptor::ReceiverRegister();
158 Register name = LoadDescriptor::NameRegister();
159 RegList regs = receiver.bit() | name.bit();
160 if (FLAG_vector_ics) {
161 regs |= VectorLoadICTrampolineDescriptor::SlotRegister().bit();
163 Generate_DebugBreakCallHelper(masm, regs, 0);
167 void DebugCodegen::GenerateStoreICDebugBreak(MacroAssembler* masm) {
168 Register receiver = StoreDescriptor::ReceiverRegister();
169 Register name = StoreDescriptor::NameRegister();
170 Register value = StoreDescriptor::ValueRegister();
171 Generate_DebugBreakCallHelper(
172 masm, receiver.bit() | name.bit() | value.bit(), 0);
176 void DebugCodegen::GenerateKeyedLoadICDebugBreak(MacroAssembler* masm) {
177 // Calling convention for keyed IC load (from ic-mips64.cc).
178 GenerateLoadICDebugBreak(masm);
182 void DebugCodegen::GenerateKeyedStoreICDebugBreak(MacroAssembler* masm) {
183 // Calling convention for IC keyed store call (from ic-mips64.cc).
184 Register receiver = StoreDescriptor::ReceiverRegister();
185 Register name = StoreDescriptor::NameRegister();
186 Register value = StoreDescriptor::ValueRegister();
187 Generate_DebugBreakCallHelper(
188 masm, receiver.bit() | name.bit() | value.bit(), 0);
192 void DebugCodegen::GenerateCompareNilICDebugBreak(MacroAssembler* masm) {
193 // Register state for CompareNil IC
194 // ----------- S t a t e -------------
196 // -----------------------------------
197 Generate_DebugBreakCallHelper(masm, a0.bit(), 0);
201 void DebugCodegen::GenerateReturnDebugBreak(MacroAssembler* masm) {
202 // In places other than IC call sites it is expected that v0 is TOS which
203 // is an object - this is not generally the case so this should be used with
205 Generate_DebugBreakCallHelper(masm, v0.bit(), 0);
209 void DebugCodegen::GenerateCallFunctionStubDebugBreak(MacroAssembler* masm) {
210 // Register state for CallFunctionStub (from code-stubs-mips.cc).
211 // ----------- S t a t e -------------
213 // -----------------------------------
214 Generate_DebugBreakCallHelper(masm, a1.bit(), 0);
218 void DebugCodegen::GenerateCallConstructStubDebugBreak(MacroAssembler* masm) {
219 // Calling convention for CallConstructStub (from code-stubs-mips.cc).
220 // ----------- S t a t e -------------
221 // -- a0 : number of arguments (not smi)
222 // -- a1 : constructor function
223 // -----------------------------------
224 Generate_DebugBreakCallHelper(masm, a1.bit() , a0.bit());
229 void DebugCodegen::GenerateCallConstructStubRecordDebugBreak(
230 MacroAssembler* masm) {
231 // Calling convention for CallConstructStub (from code-stubs-mips.cc).
232 // ----------- S t a t e -------------
233 // -- a0 : number of arguments (not smi)
234 // -- a1 : constructor function
235 // -- a2 : feedback array
236 // -- a3 : feedback slot (smi)
237 // -----------------------------------
238 Generate_DebugBreakCallHelper(masm, a1.bit() | a2.bit() | a3.bit(), a0.bit());
242 void DebugCodegen::GenerateSlot(MacroAssembler* masm) {
243 // Generate enough nop's to make space for a call instruction. Avoid emitting
244 // the trampoline pool in the debug break slot code.
245 Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm);
246 Label check_codesize;
247 __ bind(&check_codesize);
248 __ RecordDebugBreakSlot();
249 for (int i = 0; i < Assembler::kDebugBreakSlotInstructions; i++) {
250 __ nop(MacroAssembler::DEBUG_BREAK_NOP);
252 DCHECK_EQ(Assembler::kDebugBreakSlotInstructions,
253 masm->InstructionsGeneratedSince(&check_codesize));
257 void DebugCodegen::GenerateSlotDebugBreak(MacroAssembler* masm) {
258 // In the places where a debug break slot is inserted no registers can contain
260 Generate_DebugBreakCallHelper(masm, 0, 0);
264 void DebugCodegen::GeneratePlainReturnLiveEdit(MacroAssembler* masm) {
269 void DebugCodegen::GenerateFrameDropperLiveEdit(MacroAssembler* masm) {
270 ExternalReference restarter_frame_function_slot =
271 ExternalReference::debug_restarter_frame_function_pointer_address(
273 __ li(at, Operand(restarter_frame_function_slot));
274 __ sw(zero_reg, MemOperand(at, 0));
276 // We do not know our frame height, but set sp based on fp.
277 __ Dsubu(sp, fp, Operand(kPointerSize));
279 __ Pop(ra, fp, a1); // Return address, Frame, Function.
281 // Load context from the function.
282 __ ld(cp, FieldMemOperand(a1, JSFunction::kContextOffset));
284 // Get function code.
285 __ ld(at, FieldMemOperand(a1, JSFunction::kSharedFunctionInfoOffset));
286 __ ld(at, FieldMemOperand(at, SharedFunctionInfo::kCodeOffset));
287 __ Daddu(t9, at, Operand(Code::kHeaderSize - kHeapObjectTag));
289 // Re-run JSFunction, a1 is function, cp is context.
294 const bool LiveEdit::kFrameDropperSupported = true;
298 } } // namespace v8::internal
300 #endif // V8_TARGET_ARCH_MIPS64