all repos — mgba @ 691c202c402c3dac350f8b90e5ffd65d2932a0a9

mGBA Game Boy Advance Emulator

src/arm/debugger/debugger.c (view raw)

  1/* Copyright (c) 2013-2016 Jeffrey Pfau
  2 *
  3 * This Source Code Form is subject to the terms of the Mozilla Public
  4 * License, v. 2.0. If a copy of the MPL was not distributed with this
  5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
  6#include <mgba/internal/arm/debugger/debugger.h>
  7
  8#include <mgba/core/core.h>
  9#include <mgba/internal/arm/arm.h>
 10#include <mgba/internal/arm/decoder.h>
 11#include <mgba/internal/arm/isa-inlines.h>
 12#include <mgba/internal/arm/debugger/memory-debugger.h>
 13#include <mgba/internal/debugger/parser.h>
 14
 15DEFINE_VECTOR(ARMDebugBreakpointList, struct ARMDebugBreakpoint);
 16
 17static struct ARMDebugBreakpoint* _lookupBreakpoint(struct ARMDebugBreakpointList* breakpoints, uint32_t address) {
 18	size_t i;
 19	for (i = 0; i < ARMDebugBreakpointListSize(breakpoints); ++i) {
 20		if (ARMDebugBreakpointListGetPointer(breakpoints, i)->d.address == address) {
 21			return ARMDebugBreakpointListGetPointer(breakpoints, i);
 22		}
 23	}
 24	return 0;
 25}
 26
 27static void _destroyBreakpoint(struct ARMDebugBreakpoint* breakpoint) {
 28	if (breakpoint->d.condition) {
 29		parseFree(breakpoint->d.condition);
 30		free(breakpoint->d.condition);
 31	}
 32}
 33
 34static void _destroyWatchpoint(struct mWatchpoint* watchpoint) {
 35	if (watchpoint->condition) {
 36		parseFree(watchpoint->condition);
 37		free(watchpoint->condition);
 38	}
 39}
 40
 41static void ARMDebuggerCheckBreakpoints(struct mDebuggerPlatform* d) {
 42	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
 43	int instructionLength;
 44	enum ExecutionMode mode = debugger->cpu->cpsr.t;
 45	if (mode == MODE_ARM) {
 46		instructionLength = WORD_SIZE_ARM;
 47	} else {
 48		instructionLength = WORD_SIZE_THUMB;
 49	}
 50	struct ARMDebugBreakpoint* breakpoint = _lookupBreakpoint(&debugger->breakpoints, debugger->cpu->gprs[ARM_PC] - instructionLength);
 51	if (!breakpoint) {
 52		return;
 53	}
 54	if (breakpoint->d.condition) {
 55		int32_t value;
 56		int segment;
 57		if (!mDebuggerEvaluateParseTree(d->p, breakpoint->d.condition, &value, &segment) || !(value || segment >= 0)) {
 58			return;
 59		}
 60	}
 61	struct mDebuggerEntryInfo info = {
 62		.address = breakpoint->d.address,
 63		.type.bp.breakType = BREAKPOINT_HARDWARE,
 64		.pointId = breakpoint->d.id
 65	};
 66	mDebuggerEnter(d->p, DEBUGGER_ENTER_BREAKPOINT, &info);
 67}
 68
 69static void ARMDebuggerInit(void* cpu, struct mDebuggerPlatform* platform);
 70static void ARMDebuggerDeinit(struct mDebuggerPlatform* platform);
 71
 72static void ARMDebuggerEnter(struct mDebuggerPlatform* d, enum mDebuggerEntryReason reason, struct mDebuggerEntryInfo* info);
 73
 74static ssize_t ARMDebuggerSetBreakpoint(struct mDebuggerPlatform*, const struct mBreakpoint*);
 75static bool ARMDebuggerClearBreakpoint(struct mDebuggerPlatform*, ssize_t id);
 76static void ARMDebuggerListBreakpoints(struct mDebuggerPlatform*, struct mBreakpointList*);
 77static ssize_t ARMDebuggerSetWatchpoint(struct mDebuggerPlatform*, const struct mWatchpoint*);
 78static void ARMDebuggerListWatchpoints(struct mDebuggerPlatform*, struct mWatchpointList*);
 79static void ARMDebuggerCheckBreakpoints(struct mDebuggerPlatform*);
 80static bool ARMDebuggerHasBreakpoints(struct mDebuggerPlatform*);
 81static void ARMDebuggerTrace(struct mDebuggerPlatform*, char* out, size_t* length);
 82static bool ARMDebuggerGetRegister(struct mDebuggerPlatform*, const char* name, int32_t* value);
 83static bool ARMDebuggerSetRegister(struct mDebuggerPlatform*, const char* name, int32_t value);
 84
 85struct mDebuggerPlatform* ARMDebuggerPlatformCreate(void) {
 86	struct mDebuggerPlatform* platform = (struct mDebuggerPlatform*) malloc(sizeof(struct ARMDebugger));
 87	platform->entered = ARMDebuggerEnter;
 88	platform->init = ARMDebuggerInit;
 89	platform->deinit = ARMDebuggerDeinit;
 90	platform->setBreakpoint = ARMDebuggerSetBreakpoint;
 91	platform->listBreakpoints = ARMDebuggerListBreakpoints;
 92	platform->clearBreakpoint = ARMDebuggerClearBreakpoint;
 93	platform->setWatchpoint = ARMDebuggerSetWatchpoint;
 94	platform->listWatchpoints = ARMDebuggerListWatchpoints;
 95	platform->checkBreakpoints = ARMDebuggerCheckBreakpoints;
 96	platform->hasBreakpoints = ARMDebuggerHasBreakpoints;
 97	platform->trace = ARMDebuggerTrace;
 98	platform->getRegister = ARMDebuggerGetRegister;
 99	platform->setRegister = ARMDebuggerSetRegister;
100	return platform;
101}
102
103void ARMDebuggerInit(void* cpu, struct mDebuggerPlatform* platform) {
104	struct ARMDebugger* debugger = (struct ARMDebugger*) platform;
105	debugger->cpu = cpu;
106	debugger->originalMemory = debugger->cpu->memory;
107	debugger->nextId = 1;
108	ARMDebugBreakpointListInit(&debugger->breakpoints, 0);
109	ARMDebugBreakpointListInit(&debugger->swBreakpoints, 0);
110	mWatchpointListInit(&debugger->watchpoints, 0);
111}
112
113void ARMDebuggerDeinit(struct mDebuggerPlatform* platform) {
114	struct ARMDebugger* debugger = (struct ARMDebugger*) platform;
115	if (debugger->clearSoftwareBreakpoint) {
116		// Clear the stack backwards in case any overlap
117		size_t b;
118		for (b = ARMDebugBreakpointListSize(&debugger->swBreakpoints); b; --b) {
119			struct ARMDebugBreakpoint* breakpoint = ARMDebugBreakpointListGetPointer(&debugger->swBreakpoints, b - 1);
120			debugger->clearSoftwareBreakpoint(debugger, breakpoint);
121		}
122	}
123	ARMDebuggerRemoveMemoryShim(debugger);
124
125	size_t i;
126	for (i = 0; i < ARMDebugBreakpointListSize(&debugger->breakpoints); ++i) {
127		_destroyBreakpoint(ARMDebugBreakpointListGetPointer(&debugger->breakpoints, i));
128	}
129	ARMDebugBreakpointListDeinit(&debugger->breakpoints);
130
131	for (i = 0; i < mWatchpointListSize(&debugger->watchpoints); ++i) {
132		_destroyWatchpoint(mWatchpointListGetPointer(&debugger->watchpoints, i));
133	}
134	ARMDebugBreakpointListDeinit(&debugger->swBreakpoints);
135	mWatchpointListDeinit(&debugger->watchpoints);
136}
137
138static void ARMDebuggerEnter(struct mDebuggerPlatform* platform, enum mDebuggerEntryReason reason, struct mDebuggerEntryInfo* info) {
139	struct ARMDebugger* debugger = (struct ARMDebugger*) platform;
140	struct ARMCore* cpu = debugger->cpu;
141	cpu->nextEvent = cpu->cycles;
142	if (reason == DEBUGGER_ENTER_BREAKPOINT) {
143		struct ARMDebugBreakpoint* breakpoint = _lookupBreakpoint(&debugger->swBreakpoints, _ARMPCAddress(cpu));
144		if (breakpoint && breakpoint->d.type == BREAKPOINT_SOFTWARE) {
145			info->address = breakpoint->d.address;
146			info->pointId = breakpoint->d.id;
147			if (debugger->clearSoftwareBreakpoint) {
148				debugger->clearSoftwareBreakpoint(debugger, breakpoint);
149			}
150
151			ARMRunFake(cpu, breakpoint->sw.opcode);
152
153			if (debugger->setSoftwareBreakpoint) {
154				debugger->setSoftwareBreakpoint(debugger, breakpoint->d.address, breakpoint->sw.mode, &breakpoint->sw.opcode);
155			}
156		}
157	}
158	if (debugger->d.p->entered) {
159		debugger->d.p->entered(debugger->d.p, reason, info);
160	}
161}
162
163ssize_t ARMDebuggerSetSoftwareBreakpoint(struct mDebuggerPlatform* d, uint32_t address, enum ExecutionMode mode) {
164	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
165	uint32_t opcode;
166	if (!debugger->setSoftwareBreakpoint || !debugger->setSoftwareBreakpoint(debugger, address, mode, &opcode)) {
167		return -1;
168	}
169
170	struct ARMDebugBreakpoint* breakpoint = ARMDebugBreakpointListAppend(&debugger->swBreakpoints);
171	ssize_t id = debugger->nextId;
172	++debugger->nextId;
173	breakpoint->d.id = id;
174	breakpoint->d.address = address & ~1; // Clear Thumb bit since it's not part of a valid address
175	breakpoint->d.segment = -1;
176	breakpoint->d.condition = NULL;
177	breakpoint->d.type = BREAKPOINT_SOFTWARE;
178	breakpoint->sw.opcode = opcode;
179	breakpoint->sw.mode = mode;
180
181	return id;
182}
183
184static ssize_t ARMDebuggerSetBreakpoint(struct mDebuggerPlatform* d, const struct mBreakpoint* info) {
185	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
186	struct ARMDebugBreakpoint* breakpoint = ARMDebugBreakpointListAppend(&debugger->breakpoints);
187	ssize_t id = debugger->nextId;
188	++debugger->nextId;
189	breakpoint->d = *info;
190	breakpoint->d.address &= ~1; // Clear Thumb bit since it's not part of a valid address
191	breakpoint->d.id = id;
192	if (info->type == BREAKPOINT_SOFTWARE) {
193		// TODO
194		abort();
195	}
196	return id;
197}
198
199static bool ARMDebuggerClearBreakpoint(struct mDebuggerPlatform* d, ssize_t id) {
200	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
201	size_t i;
202
203	struct ARMDebugBreakpointList* breakpoints = &debugger->breakpoints;
204	for (i = 0; i < ARMDebugBreakpointListSize(breakpoints); ++i) {
205		if (ARMDebugBreakpointListGetPointer(breakpoints, i)->d.id == id) {
206			_destroyBreakpoint(ARMDebugBreakpointListGetPointer(breakpoints, i));
207			ARMDebugBreakpointListShift(breakpoints, i, 1);
208			return true;
209		}
210	}
211
212	struct ARMDebugBreakpointList* swBreakpoints = &debugger->swBreakpoints;
213	if (debugger->clearSoftwareBreakpoint) {
214		for (i = 0; i < ARMDebugBreakpointListSize(swBreakpoints); ++i) {
215			if (ARMDebugBreakpointListGetPointer(swBreakpoints, i)->d.id == id) {
216				debugger->clearSoftwareBreakpoint(debugger, ARMDebugBreakpointListGetPointer(swBreakpoints, i));
217				ARMDebugBreakpointListShift(swBreakpoints, i, 1);
218				return true;
219			}
220		}
221	}
222
223	struct mWatchpointList* watchpoints = &debugger->watchpoints;
224	for (i = 0; i < mWatchpointListSize(watchpoints); ++i) {
225		if (mWatchpointListGetPointer(watchpoints, i)->id == id) {
226			_destroyWatchpoint(mWatchpointListGetPointer(watchpoints, i));
227			mWatchpointListShift(watchpoints, i, 1);
228			if (!mWatchpointListSize(&debugger->watchpoints)) {
229				ARMDebuggerRemoveMemoryShim(debugger);
230			}
231			return true;
232		}
233	}
234	return false;
235}
236
237static void ARMDebuggerListBreakpoints(struct mDebuggerPlatform* d, struct mBreakpointList* list) {
238	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
239	mBreakpointListClear(list);
240	size_t i, s;
241	for (i = 0, s = 0; i < ARMDebugBreakpointListSize(&debugger->breakpoints) || s < ARMDebugBreakpointListSize(&debugger->swBreakpoints);) {
242		struct ARMDebugBreakpoint* hw = NULL;
243		struct ARMDebugBreakpoint* sw = NULL;
244		if (i < ARMDebugBreakpointListSize(&debugger->breakpoints)) {
245			hw = ARMDebugBreakpointListGetPointer(&debugger->breakpoints, i);
246		}
247		if (s < ARMDebugBreakpointListSize(&debugger->swBreakpoints)) {
248			sw = ARMDebugBreakpointListGetPointer(&debugger->swBreakpoints, s);
249		}
250		struct mBreakpoint* b = mBreakpointListAppend(list);
251		if (hw && sw) {
252			if (hw->d.id < sw->d.id) {
253				*b = hw->d;
254				++i;
255			} else {
256				*b = sw->d;
257				++s;
258			}
259		} else if (hw) {
260			*b = hw->d;
261			++i;
262		} else if (sw) {
263			*b = sw->d;
264			++s;		
265		} else {
266			abort(); // Should be unreachable
267		}
268	}
269}
270
271static bool ARMDebuggerHasBreakpoints(struct mDebuggerPlatform* d) {
272	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
273	return ARMDebugBreakpointListSize(&debugger->breakpoints) || mWatchpointListSize(&debugger->watchpoints);
274}
275
276static ssize_t ARMDebuggerSetWatchpoint(struct mDebuggerPlatform* d, const struct mWatchpoint* info) {
277	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
278	if (!mWatchpointListSize(&debugger->watchpoints)) {
279		ARMDebuggerInstallMemoryShim(debugger);
280	}
281	struct mWatchpoint* watchpoint = mWatchpointListAppend(&debugger->watchpoints);
282	ssize_t id = debugger->nextId;
283	++debugger->nextId;
284	*watchpoint = *info;
285	watchpoint->id = id;
286	return id;
287}
288
289static void ARMDebuggerListWatchpoints(struct mDebuggerPlatform* d, struct mWatchpointList* list) {
290	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
291	mWatchpointListClear(list);
292	mWatchpointListCopy(list, &debugger->watchpoints);
293}
294
295static void ARMDebuggerTrace(struct mDebuggerPlatform* d, char* out, size_t* length) {
296	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
297	struct ARMCore* cpu = debugger->cpu;
298
299	char disassembly[64];
300
301	struct ARMInstructionInfo info;
302	if (cpu->executionMode == MODE_ARM) {
303		uint32_t instruction = cpu->prefetch[0];
304		sprintf(disassembly, "%08X: ", instruction);
305		ARMDecodeARM(instruction, &info);
306		ARMDisassemble(&info, cpu->gprs[ARM_PC], disassembly + strlen("00000000: "), sizeof(disassembly) - strlen("00000000: "));
307	} else {
308		struct ARMInstructionInfo info2;
309		struct ARMInstructionInfo combined;
310		uint16_t instruction = cpu->prefetch[0];
311		uint16_t instruction2 = cpu->prefetch[1];
312		ARMDecodeThumb(instruction, &info);
313		ARMDecodeThumb(instruction2, &info2);
314		if (ARMDecodeThumbCombine(&info, &info2, &combined)) {
315			sprintf(disassembly, "%04X%04X: ", instruction, instruction2);
316			ARMDisassemble(&combined, cpu->gprs[ARM_PC], disassembly + strlen("00000000: "), sizeof(disassembly) - strlen("00000000: "));
317		} else {
318			sprintf(disassembly, "    %04X: ", instruction);
319			ARMDisassemble(&info, cpu->gprs[ARM_PC], disassembly + strlen("00000000: "), sizeof(disassembly) - strlen("00000000: "));
320		}
321	}
322
323	*length = snprintf(out, *length, "%08X %08X %08X %08X %08X %08X %08X %08X %08X %08X %08X %08X %08X %08X %08X %08X cpsr: %08X | %s",
324		               cpu->gprs[0],  cpu->gprs[1],  cpu->gprs[2],  cpu->gprs[3],
325		               cpu->gprs[4],  cpu->gprs[5],  cpu->gprs[6],  cpu->gprs[7],
326		               cpu->gprs[8],  cpu->gprs[9],  cpu->gprs[10], cpu->gprs[11],
327		               cpu->gprs[12], cpu->gprs[13], cpu->gprs[14], cpu->gprs[15],
328		               cpu->cpsr.packed, disassembly);
329}
330
331bool ARMDebuggerGetRegister(struct mDebuggerPlatform* d, const char* name, int32_t* value) {
332	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
333	struct ARMCore* cpu = debugger->cpu;
334
335	if (strcmp(name, "sp") == 0) {
336		*value = cpu->gprs[ARM_SP];
337		return true;
338	}
339	if (strcmp(name, "lr") == 0) {
340		*value = cpu->gprs[ARM_LR];
341		return true;
342	}
343	if (strcmp(name, "pc") == 0) {
344		*value = cpu->gprs[ARM_PC];
345		return true;
346	}
347	if (strcmp(name, "cpsr") == 0) {
348		*value = cpu->cpsr.packed;
349		return true;
350	}
351	// TODO: test if mode has SPSR
352	if (strcmp(name, "spsr") == 0) {
353		*value = cpu->spsr.packed;
354		return true;
355	}
356	if (name[0] == 'r') {
357		char* end;
358		uint32_t reg = strtoul(&name[1], &end, 10);
359		if (reg <= ARM_PC) {
360			*value = cpu->gprs[reg];
361			return true;
362		}
363	}
364	return false;
365}
366
367bool ARMDebuggerSetRegister(struct mDebuggerPlatform* d, const char* name, int32_t value) {
368	struct ARMDebugger* debugger = (struct ARMDebugger*) d;
369	struct ARMCore* cpu = debugger->cpu;
370
371	if (strcmp(name, "sp") == 0) {
372		cpu->gprs[ARM_SP] = value;
373		return true;
374	}
375	if (strcmp(name, "lr") == 0) {
376		cpu->gprs[ARM_LR] = value;
377		return true;
378	}
379	if (strcmp(name, "pc") == 0) {
380		cpu->gprs[ARM_PC] = value;
381		if (cpu->executionMode == MODE_ARM) {
382			ARMWritePC(cpu);
383		} else {
384			ThumbWritePC(cpu);
385		}
386		return true;
387	}
388	if (name[0] == 'r') {
389		char* end;
390		uint32_t reg = strtoul(&name[1], &end, 10);
391		if (reg > ARM_PC) {
392			return false;
393		}
394		cpu->gprs[reg] = value;
395		if (reg == ARM_PC) {
396			if (cpu->executionMode == MODE_ARM) {
397				ARMWritePC(cpu);
398			} else {
399				ThumbWritePC(cpu);
400			}
401		}
402		return true;
403	}
404	return false;
405}