Teach the branch folder to update debug info if it removes blocks with line

# notes in it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31026 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2006-10-17 23:17:27 +00:00
parent a97906b6e6
commit 683747abb8

View File

@ -17,6 +17,7 @@
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/MachineDebugInfo.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
@ -29,9 +30,11 @@ namespace {
virtual bool runOnMachineFunction(MachineFunction &MF);
virtual const char *getPassName() const { return "Control Flow Optimizer"; }
const TargetInstrInfo *TII;
MachineDebugInfo *MDI;
bool MadeChange;
private:
void OptimizeBlock(MachineFunction::iterator MBB);
void RemoveDeadBlock(MachineBasicBlock *MBB);
};
}
@ -39,12 +42,30 @@ FunctionPass *llvm::createBranchFoldingPass() { return new BranchFolder(); }
/// RemoveDeadBlock - Remove the specified dead machine basic block from the
/// function, updating the CFG.
static void RemoveDeadBlock(MachineBasicBlock *MBB) {
void BranchFolder::RemoveDeadBlock(MachineBasicBlock *MBB) {
assert(MBB->pred_empty() && "MBB must be dead!");
MachineFunction *MF = MBB->getParent();
// drop all successors.
while (!MBB->succ_empty())
MBB->removeSuccessor(MBB->succ_end()-1);
// If there is DWARF info to active, check to see if there are any DWARF_LABEL
// records in the basic block. If so, unregister them from MachineDebugInfo.
if (MDI && !MBB->empty()) {
unsigned DWARF_LABELOpc = TII->getDWARF_LABELOpcode();
assert(DWARF_LABELOpc &&
"Target supports dwarf but didn't implement getDWARF_LABELOpcode!");
for (MachineBasicBlock::iterator I = MBB->begin(), E = MBB->end();
I != E; ++I) {
if ((unsigned)I->getOpcode() == DWARF_LABELOpc) {
// The label ID # is always operand #0, an immediate.
MDI->RemoveLabelInfo(I->getOperand(0).getImm());
}
}
}
// Remove the block.
MF->getBasicBlockList().erase(MBB);
}
@ -53,7 +74,7 @@ bool BranchFolder::runOnMachineFunction(MachineFunction &MF) {
TII = MF.getTarget().getInstrInfo();
if (!TII) return false;
//MF.dump();
MDI = getAnalysisToUpdate<MachineDebugInfo>();
bool EverMadeChange = false;
MadeChange = true;