From 68cc34bb79d93ca090ffcbae9c276cc2fc0386e5 Mon Sep 17 00:00:00 2001 From: Ben Vanik Date: Sun, 20 Jan 2013 17:27:49 -0800 Subject: [PATCH] Fixing up basic block targets and such. --- include/xenia/cpu/sdb.h | 21 +++++- src/cpu/sdb.cc | 145 ++++++++++++++++++++++++++++++++-------- 2 files changed, 135 insertions(+), 31 deletions(-) diff --git a/include/xenia/cpu/sdb.h b/include/xenia/cpu/sdb.h index cfae9e9c8..1c5252adb 100644 --- a/include/xenia/cpu/sdb.h +++ b/include/xenia/cpu/sdb.h @@ -62,12 +62,25 @@ class ExceptionEntrySymbol; class FunctionBlock { public: + enum TargetType { + kTargetUnknown = 0, + kTargetBlock = 1, + kTargetFunction = 2, + kTargetLR = 3, + kTargetNone = 4, + }; + uint32_t start_address; uint32_t end_address; vector incoming_blocks; - FunctionBlock* outgoing_block; - uint32_t outgoing_address; + + TargetType outgoing_type; + uint32_t outgoing_address; + union { + FunctionSymbol* outgoing_function; + FunctionBlock* outgoing_block; + }; }; class FunctionSymbol : public Symbol { @@ -85,6 +98,9 @@ public: FunctionSymbol() : Symbol(Function) {} virtual ~FunctionSymbol() {} + FunctionBlock* GetBlock(uint32_t address); + FunctionBlock* SplitBlock(uint32_t address); + uint32_t start_address; uint32_t end_address; char *name; @@ -146,6 +162,7 @@ private: int AddImports(const xe_xex2_import_library_t *library); int AddMethodHints(); int AnalyzeFunction(FunctionSymbol* fn); + int CompleteFunctionGraph(FunctionSymbol* fn); bool FillHoles(); int FlushQueue(); diff --git a/src/cpu/sdb.cc b/src/cpu/sdb.cc index 1730f9929..cbcb6cb24 100644 --- a/src/cpu/sdb.cc +++ b/src/cpu/sdb.cc @@ -22,6 +22,44 @@ using namespace xe::cpu::sdb; using namespace xe::kernel; +FunctionBlock* FunctionSymbol::GetBlock(uint32_t address) { + std::map::iterator it = blocks.find(address); + if (it != blocks.end()) { + return it->second; + } + return NULL; +} + +FunctionBlock* FunctionSymbol::SplitBlock(uint32_t address) { + // Scan to find the block that contains the address. + for (std::map::iterator it = blocks.begin(); + it != blocks.end(); ++it) { + FunctionBlock* block = it->second; + if (address == block->start_address) { + // No need for a split. + return block; + } else if (address >= block->start_address && + address <= block->end_address + 4) { + // Inside this block. + // Since we know we are starting inside of the block we split downwards. + FunctionBlock* new_block = new FunctionBlock(); + new_block->start_address = address; + new_block->end_address = block->end_address; + new_block->outgoing_type = block->outgoing_type; + new_block->outgoing_address = block->outgoing_address; + new_block->outgoing_block = block->outgoing_block; + blocks.insert(std::pair(address, new_block)); + // Patch up old block. + block->end_address = address - 4; + block->outgoing_type = FunctionBlock::kTargetNone; + block->outgoing_address = 0; + block->outgoing_block = NULL; + return new_block; + } + } + return NULL; +} + SymbolDatabase::SymbolDatabase(xe_memory_ref memory, UserModule* module) { memory_ = xe_memory_retain(memory); module_ = module; @@ -74,6 +112,14 @@ int SymbolDatabase::Analyze() { FlushQueue(); } + // Run a pass over all functions and link up their extended data. + // This can only be performed after we have all functions and basic blocks. + for (SymbolMap::iterator it = symbols_.begin(); it != symbols_.end(); ++it) { + if (it->second->symbol_type == Symbol::Function) { + CompleteFunctionGraph(static_cast(it->second)); + } + } + return 0; } @@ -349,11 +395,6 @@ int SymbolDatabase::AddMethodHints() { return 0; } -bool SymbolDatabase::IsRestGprLr(uint32_t addr) { - FunctionSymbol* fn = GetFunction(addr); - return fn && (fn->flags & FunctionSymbol::kFlagRestGprLr); -} - int SymbolDatabase::AnalyzeFunction(FunctionSymbol* fn) { // Ignore functions already analyzed. if (fn->blocks.size()) { @@ -436,6 +477,7 @@ int SymbolDatabase::AnalyzeFunction(FunctionSymbol* fn) { if (i.code == 0x4E800020) { // blr -- unconditional branch to LR. // This is generally a return. + block->outgoing_type = FunctionBlock::kTargetLR; if (furthest_target > addr) { // Remaining targets within function, not end. XELOGSDB("ignoring blr %.8X (branch to %.8X)\n", addr, furthest_target); @@ -448,11 +490,13 @@ int SymbolDatabase::AnalyzeFunction(FunctionSymbol* fn) { } else if (i.type->opcode == 0x48000000) { // b/ba/bl/bla uint32_t target = XEEXTS26(i.I.LI << 2) + (i.I.AA ? 0 : (int32_t)addr); + block->outgoing_address = target; if (i.I.LK) { XELOGSDB("bl %.8X -> %.8X\n", addr, target); - // Queue target if needed. + // Queue call target if needed. + GetOrInsertFunction(target); } else { XELOGSDB("b %.8X -> %.8X\n", addr, target); // If the target is back into the function and there's no further target @@ -478,6 +522,7 @@ int SymbolDatabase::AnalyzeFunction(FunctionSymbol* fn) { } else if (i.type->opcode == 0x40000000) { // bc/bca/bcl/bcla uint32_t target = XEEXTS16(i.B.BD << 2) + (i.B.AA ? 0 : (int32_t)addr); + block->outgoing_address = target; if (i.B.LK) { XELOGSDB("bcl %.8X -> %.8X\n", addr, target); } else { @@ -537,34 +582,43 @@ int SymbolDatabase::AnalyzeFunction(FunctionSymbol* fn) { return 0; } -int SymbolDatabase::FlushQueue() { - while (scan_queue_.size()) { - FunctionSymbol* fn = scan_queue_.front(); - scan_queue_.pop_front(); - if (AnalyzeFunction(fn)) { - XELOGSDB("Aborting analysis!\n"); - return 1; +int SymbolDatabase::CompleteFunctionGraph(FunctionSymbol* fn) { + // Find variable accesses. + // TODO(benvanik): data analysis to find variable accesses. + + // For each basic block: + // - find outgoing target block or function + for (std::map::iterator it = fn->blocks.begin(); + it != fn->blocks.end(); ++it) { + FunctionBlock* block = it->second; + + // If we have some address try to see what it is. + if (block->outgoing_address) { + if (block->outgoing_address >= fn->start_address && + block->outgoing_address <= fn->end_address) { + // Branch into a block in this function. + block->outgoing_type = FunctionBlock::kTargetBlock; + block->outgoing_block = fn->GetBlock(block->outgoing_address); + if (!block->outgoing_block) { + // Block target not found - we may need to split. + block->outgoing_block = fn->SplitBlock(block->outgoing_address); + } + if (!block->outgoing_block) { + printf("block target not found: %.8X\n", block->outgoing_address); + } + } else { + // Function call. + block->outgoing_type = FunctionBlock::kTargetFunction; + block->outgoing_function = GetFunction(block->outgoing_address); + if (!block->outgoing_function) { + printf("call target not found: %.8X\n", block->outgoing_address); + } + } } } return 0; } -bool SymbolDatabase::IsValueInTextRange(uint32_t value) { - const xe_xex2_header_t* header = module_->xex_header(); - for (size_t n = 0, i = 0; n < header->section_count; n++) { - const xe_xex2_section_t* section = &header->sections[n]; - const size_t start_address = - header->exe_address + (i * xe_xex2_section_length); - const size_t end_address = - start_address + (section->info.page_count * xe_xex2_section_length); - if (value >= start_address && value < end_address) { - return section->info.type == XEX_SECTION_CODE; - } - i += section->info.page_count; - } - return false; -} - typedef struct { uint32_t start_address; uint32_t end_address; @@ -648,3 +702,36 @@ bool SymbolDatabase::FillHoles() { return holes.size() > 0; } + +int SymbolDatabase::FlushQueue() { + while (scan_queue_.size()) { + FunctionSymbol* fn = scan_queue_.front(); + scan_queue_.pop_front(); + if (AnalyzeFunction(fn)) { + XELOGSDB("Aborting analysis!\n"); + return 1; + } + } + return 0; +} + +bool SymbolDatabase::IsValueInTextRange(uint32_t value) { + const xe_xex2_header_t* header = module_->xex_header(); + for (size_t n = 0, i = 0; n < header->section_count; n++) { + const xe_xex2_section_t* section = &header->sections[n]; + const size_t start_address = + header->exe_address + (i * xe_xex2_section_length); + const size_t end_address = + start_address + (section->info.page_count * xe_xex2_section_length); + if (value >= start_address && value < end_address) { + return section->info.type == XEX_SECTION_CODE; + } + i += section->info.page_count; + } + return false; +} + +bool SymbolDatabase::IsRestGprLr(uint32_t addr) { + FunctionSymbol* fn = GetFunction(addr); + return fn && (fn->flags & FunctionSymbol::kFlagRestGprLr); +}