Identify end of prologue (and beginning of function body) using DW_LNS_set_prologue_end line table opcode.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131194 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index fd87224..aa1f6c7 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -1483,12 +1483,17 @@
if (!MI->isDebugValue()) {
DebugLoc DL = MI->getDebugLoc();
if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
+ unsigned Flags = DWARF2_FLAG_IS_STMT;
PrevInstLoc = DL;
+ if (DL == PrologEndLoc) {
+ Flags |= DWARF2_FLAG_PROLOGUE_END;
+ PrologEndLoc = DebugLoc();
+ }
if (!DL.isUnknown()) {
const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
- recordSourceLine(DL.getLine(), DL.getCol(), Scope);
+ recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
} else
- recordSourceLine(0, 0, 0);
+ recordSourceLine(0, 0, 0, 0);
}
}
@@ -1800,21 +1805,6 @@
}
}
-/// FindFirstDebugLoc - Find the first debug location in the function. This
-/// is intended to be an approximation for the source position of the
-/// beginning of the function.
-static DebugLoc FindFirstDebugLoc(const MachineFunction *MF) {
- for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
- I != E; ++I)
- for (MachineBasicBlock::const_iterator MBBI = I->begin(), MBBE = I->end();
- MBBI != MBBE; ++MBBI) {
- DebugLoc DL = MBBI->getDebugLoc();
- if (!DL.isUnknown())
- return DL;
- }
- return DebugLoc();
-}
-
/// getScopeNode - Get MDNode for DebugLoc's scope.
static MDNode *getScopeNode(DebugLoc DL, const LLVMContext &Ctx) {
if (MDNode *InlinedAt = DL.getInlinedAt(Ctx))
@@ -1822,6 +1812,16 @@
return DL.getScope(Ctx);
}
+/// getFnDebugLoc - Walk up the scope chain of given debug loc and find
+/// line number info for the function.
+static DebugLoc getFnDebugLoc(DebugLoc DL, const LLVMContext &Ctx) {
+ const MDNode *Scope = getScopeNode(DL, Ctx);
+ DISubprogram SP = getDISubprogram(Scope);
+ if (SP.Verify())
+ return DebugLoc::get(SP.getLineNumber(), 0, SP);
+ return DebugLoc();
+}
+
/// beginFunction - Gather pre-function debug information. Assumes being
/// emitted immediately after the function entry point.
void DwarfDebug::beginFunction(const MachineFunction *MF) {
@@ -1833,35 +1833,11 @@
// Assumes in correct section after the entry point.
Asm->OutStreamer.EmitLabel(FunctionBeginSym);
- // Emit label for the implicitly defined dbg.stoppoint at the start of the
- // function.
- DebugLoc FDL = FindFirstDebugLoc(MF);
- if (FDL.isUnknown()) return;
-
- const MDNode *Scope = getScopeNode(FDL, MF->getFunction()->getContext());
- const MDNode *TheScope = 0;
-
- DISubprogram SP = getDISubprogram(Scope);
- unsigned Line, Col;
- if (SP.Verify()) {
- Line = SP.getLineNumber();
- Col = 0;
- TheScope = SP;
- } else {
- Line = FDL.getLine();
- Col = FDL.getCol();
- TheScope = Scope;
- }
-
- recordSourceLine(Line, Col, TheScope);
-
assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned");
/// ProcessedArgs - Collection of arguments already processed.
SmallPtrSet<const MDNode *, 8> ProcessedArgs;
-
const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo();
-
/// LiveUserVar - Map physreg numbers to the MDNode they contain.
std::vector<const MDNode*> LiveUserVar(TRI->getNumRegs());
@@ -1927,6 +1903,11 @@
if (!MI->isLabel())
AtBlockEntry = false;
+ // First known non DBG_VALUE location marks beginning of function
+ // body.
+ if (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown())
+ PrologEndLoc = MI->getDebugLoc();
+
// Check if the instruction clobbers any registers with debug vars.
for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(),
MOE = MI->operands_end(); MOI != MOE; ++MOI) {
@@ -1995,6 +1976,15 @@
PrevInstLoc = DebugLoc();
PrevLabel = FunctionBeginSym;
+
+ // Record beginning of function.
+ if (!PrologEndLoc.isUnknown()) {
+ DebugLoc FnStartDL = getFnDebugLoc(PrologEndLoc,
+ MF->getFunction()->getContext());
+ recordSourceLine(FnStartDL.getLine(), FnStartDL.getCol(),
+ FnStartDL.getScope(MF->getFunction()->getContext()),
+ DWARF2_FLAG_IS_STMT);
+ }
}
/// endFunction - Gather and emit post-function debug information.
@@ -2109,7 +2099,8 @@
/// recordSourceLine - Register a source line with debug info. Returns the
/// unique label that was emitted and which provides correspondence to
/// the source line list.
-void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S){
+void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
+ unsigned Flags) {
StringRef Fn;
StringRef Dir;
unsigned Src = 1;
@@ -2137,7 +2128,7 @@
Src = GetOrCreateSourceID(Fn, Dir);
}
- Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, DWARF2_FLAG_IS_STMT,
+ Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags,
0, 0, Fn);
}