1/* Copyright (c) 2013-2014 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 "memory-debugger.h"
  7
  8#include "debugger.h"
  9
 10#include <string.h>
 11
 12static bool _checkWatchpoints(struct ARMDebugger* debugger, uint32_t address, struct DebuggerEntryInfo* info, int width);
 13
 14static uint32_t _popcount32(unsigned bits) {
 15	bits = bits - ((bits >> 1) & 0x55555555);
 16	bits = (bits & 0x33333333) + ((bits >> 2) & 0x33333333);
 17	return (((bits + (bits >> 4)) & 0xF0F0F0F) * 0x1010101) >> 24;
 18}
 19
 20#define FIND_DEBUGGER(DEBUGGER, CPU) \
 21	{ \
 22		DEBUGGER = 0; \
 23		int i; \
 24		for (i = 0; i < CPU->numComponents; ++i) { \
 25			if (CPU->components[i]->id == ARM_DEBUGGER_ID) { \
 26				DEBUGGER = (struct ARMDebugger*) cpu->components[i]; \
 27				break; \
 28			} \
 29		} \
 30	}
 31
 32#define CREATE_SHIM(NAME, RETURN, TYPES, ARGS...) \
 33	static RETURN ARMDebuggerShim_ ## NAME TYPES { \
 34		struct ARMDebugger* debugger; \
 35		FIND_DEBUGGER(debugger, cpu); \
 36		return debugger->originalMemory.NAME(cpu, ARGS); \
 37	}
 38
 39#define CREATE_WATCHPOINT_SHIM(NAME, WIDTH, RETURN, TYPES, ARGS...) \
 40	static RETURN ARMDebuggerShim_ ## NAME TYPES { \
 41		struct ARMDebugger* debugger; \
 42		FIND_DEBUGGER(debugger, cpu); \
 43		struct DebuggerEntryInfo info = { }; \
 44		if (_checkWatchpoints(debugger, address, &info, WIDTH)) { \
 45			ARMDebuggerEnter(debugger, DEBUGGER_ENTER_WATCHPOINT, &info); \
 46		} \
 47		return debugger->originalMemory.NAME(cpu, ARGS); \
 48	}
 49
 50#define CREATE_MULTIPLE_WATCHPOINT_SHIM(NAME) \
 51	static uint32_t ARMDebuggerShim_ ## NAME (struct ARMCore* cpu, uint32_t address, int mask, enum LSMDirection direction, int* cycleCounter) { \
 52		struct ARMDebugger* debugger; \
 53		FIND_DEBUGGER(debugger, cpu); \
 54		uint32_t popcount = _popcount32(mask); \
 55		int offset = 4; \
 56		int base = address; \
 57		if (direction & LSM_D) { \
 58			offset = -4; \
 59			base -= (popcount << 2) - 4; \
 60		} \
 61		if (direction & LSM_B) { \
 62			base += offset; \
 63		} \
 64		unsigned i; \
 65		for (i = 0; i < popcount; ++i) { \
 66			struct DebuggerEntryInfo info = { }; \
 67			if (_checkWatchpoints(debugger, base + 4 * i, &info, 4)) { \
 68				ARMDebuggerEnter(debugger, DEBUGGER_ENTER_WATCHPOINT, &info); \
 69			} \
 70		} \
 71		return debugger->originalMemory.NAME(cpu, address, mask, direction, cycleCounter); \
 72	}
 73
 74CREATE_WATCHPOINT_SHIM(load32, 4, uint32_t, (struct ARMCore* cpu, uint32_t address, int* cycleCounter), address, cycleCounter)
 75CREATE_WATCHPOINT_SHIM(load16, 2, uint32_t, (struct ARMCore* cpu, uint32_t address, int* cycleCounter), address, cycleCounter)
 76CREATE_WATCHPOINT_SHIM(load8, 1, uint32_t, (struct ARMCore* cpu, uint32_t address, int* cycleCounter), address, cycleCounter)
 77CREATE_WATCHPOINT_SHIM(store32, 4, void, (struct ARMCore* cpu, uint32_t address, int32_t value, int* cycleCounter), address, value, cycleCounter)
 78CREATE_WATCHPOINT_SHIM(store16, 2, void, (struct ARMCore* cpu, uint32_t address, int16_t value, int* cycleCounter), address, value, cycleCounter)
 79CREATE_WATCHPOINT_SHIM(store8, 1, void, (struct ARMCore* cpu, uint32_t address, int8_t value, int* cycleCounter), address, value, cycleCounter)
 80CREATE_MULTIPLE_WATCHPOINT_SHIM(loadMultiple)
 81CREATE_MULTIPLE_WATCHPOINT_SHIM(storeMultiple)
 82CREATE_SHIM(setActiveRegion, void, (struct ARMCore* cpu, uint32_t address), address)
 83
 84static bool _checkWatchpoints(struct ARMDebugger* debugger, uint32_t address, struct DebuggerEntryInfo* info, int width) {
 85	--width;
 86	struct DebugWatchpoint* watchpoints;
 87	for (watchpoints = debugger->watchpoints; watchpoints; watchpoints = watchpoints->next) {
 88		if (!((watchpoints->address ^ address) & ~width)) {
 89			switch (width + 1) {
 90			case 1:
 91				info->oldValue = debugger->originalMemory.load8(debugger->cpu, address, 0);
 92				break;
 93			case 2:
 94				info->oldValue = debugger->originalMemory.load16(debugger->cpu, address, 0);
 95				break;
 96			case 4:
 97				info->oldValue = debugger->originalMemory.load32(debugger->cpu, address, 0);
 98				break;
 99			}
100			info->address = address;
101			info->watchType = watchpoints->type;
102			return true;
103		}
104	}
105	return false;
106}
107
108void ARMDebuggerInstallMemoryShim(struct ARMDebugger* debugger) {
109	debugger->originalMemory = debugger->cpu->memory;
110	debugger->cpu->memory.store32 = ARMDebuggerShim_store32;
111	debugger->cpu->memory.store16 = ARMDebuggerShim_store16;
112	debugger->cpu->memory.store8 = ARMDebuggerShim_store8;
113	debugger->cpu->memory.load32 = ARMDebuggerShim_load32;
114	debugger->cpu->memory.load16 = ARMDebuggerShim_load16;
115	debugger->cpu->memory.load8 = ARMDebuggerShim_load8;
116	debugger->cpu->memory.storeMultiple = ARMDebuggerShim_storeMultiple;
117	debugger->cpu->memory.loadMultiple = ARMDebuggerShim_loadMultiple;
118	debugger->cpu->memory.setActiveRegion = ARMDebuggerShim_setActiveRegion;
119}
120
121void ARMDebuggerRemoveMemoryShim(struct ARMDebugger* debugger) {
122	debugger->cpu->memory.store32 = debugger->originalMemory.store32;
123	debugger->cpu->memory.store16 = debugger->originalMemory.store16;
124	debugger->cpu->memory.store8 = debugger->originalMemory.store8;
125	debugger->cpu->memory.load32 = debugger->originalMemory.load32;
126	debugger->cpu->memory.load16 = debugger->originalMemory.load16;
127	debugger->cpu->memory.load8 = debugger->originalMemory.load8;
128	debugger->cpu->memory.storeMultiple = debugger->originalMemory.storeMultiple;
129	debugger->cpu->memory.loadMultiple = debugger->originalMemory.loadMultiple;
130	debugger->cpu->memory.setActiveRegion = debugger->originalMemory.setActiveRegion;
131}