In gcov profiling, give all functions an extra unified return block. This is

necessary since gcov counts transitions between blocks. It can't see if you've
run every line in a straight-line function, so we add an edge for it to notice.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129905 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nick Lewycky 2011-04-21 03:18:00 +00:00
parent 17df2c3240
commit a4c4c0e129

View File

@ -244,6 +244,7 @@ namespace {
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
blocks[BB] = new GCOVBlock(i++, os);
}
return_block = new GCOVBlock(i++, os);
WriteBytes(function_tag, 4);
uint32_t block_len = 1 + 1 + 1 + LengthOfGCOVString(SP.getName()) +
@ -259,17 +260,22 @@ namespace {
~GCOVFunction() {
DeleteContainerSeconds(blocks);
delete return_block;
}
GCOVBlock &GetBlock(BasicBlock *BB) {
return *blocks[BB];
}
GCOVBlock &GetReturnBlock() {
return *return_block;
}
void WriteOut() {
// Emit count of blocks.
WriteBytes(block_tag, 4);
Write(blocks.size());
for (int i = 0, e = blocks.size(); i != e; ++i) {
Write(blocks.size() + 1);
for (int i = 0, e = blocks.size() + 1; i != e; ++i) {
Write(0); // No flags on our blocks.
}
@ -297,6 +303,7 @@ namespace {
private:
DenseMap<BasicBlock *, GCOVBlock *> blocks;
GCOVBlock *return_block;
};
}
@ -347,6 +354,8 @@ void GCOVProfiler::EmitGCNO(DebugInfoFinder &DIF) {
for (int i = 0; i != successors; ++i) {
block.AddEdge(function.GetBlock(TI->getSuccessor(i)));
}
} else if (isa<ReturnInst>(TI)) {
block.AddEdge(function.GetReturnBlock());
}
uint32_t line = 0;
@ -383,11 +392,13 @@ bool GCOVProfiler::EmitProfileArcs(DebugInfoFinder &DIF) {
DISubprogram SP(*SPI);
Function *F = SP.getFunction();
// TODO: GCOV format requires a distinct unified exit block.
unsigned edges = 0;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
TerminatorInst *TI = BB->getTerminator();
edges += TI->getNumSuccessors();
if (isa<ReturnInst>(TI))
++edges;
else
edges += TI->getNumSuccessors();
}
const ArrayType *counter_type =
@ -406,7 +417,8 @@ bool GCOVProfiler::EmitProfileArcs(DebugInfoFinder &DIF) {
unsigned edge_num = 0;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
TerminatorInst *TI = BB->getTerminator();
if (int successors = TI->getNumSuccessors()) {
int successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
if (successors) {
IRBuilder<> builder(TI);
if (successors == 1) {