This reapplies r207235 with an additional bugfixes caught by the msan
buildbot - do not insert debug intrinsics before phi nodes.
Debug info for optimized code: Support variables that are on the stack and
described by DBG_VALUEs during their lifetime.
Previously, when a variable was at a FrameIndex for any part of its
lifetime, this would shadow all other DBG_VALUEs and only a single
fbreg location would be emitted, which in fact is only valid for a small
range and not the entire lexical scope of the variable. The included
dbg-value-const-byref testcase demonstrates this.
This patch fixes this by
Local
- emitting dbg.value intrinsics for allocas that are passed by reference
- dropping all dbg.declares (they are now fully lowered to dbg.values)
SelectionDAG
- renamed constructors for SDDbgValue for better readability.
- fix UserValue::match() to handle indirect values correctly
- not inserting an MMI table entries for dbg.values that describe allocas.
- lowering dbg.values that describe allocas into *indirect* DBG_VALUEs.
CodeGenPrepare
- leaving dbg.values for an alloca were they are (see comment)
Other
- regenerated/updated instcombine.ll testcase and included source
rdar://problem/16679879
http://reviews.llvm.org/D3374
llvm-svn: 207269
diff --git a/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h b/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h
index b62bd62..ee54292 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h
+++ b/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h
@@ -45,14 +45,17 @@
unsigned FrameIx; // valid for stack objects
} u;
MDNode *mdPtr;
+ bool IsIndirect;
uint64_t Offset;
DebugLoc DL;
unsigned Order;
bool Invalid;
public:
// Constructor for non-constants.
- SDDbgValue(MDNode *mdP, SDNode *N, unsigned R, uint64_t off, DebugLoc dl,
- unsigned O) : mdPtr(mdP), Offset(off), DL(dl), Order(O),
+ SDDbgValue(MDNode *mdP, SDNode *N, unsigned R,
+ bool indir, uint64_t off, DebugLoc dl,
+ unsigned O) : mdPtr(mdP), IsIndirect(indir),
+ Offset(off), DL(dl), Order(O),
Invalid(false) {
kind = SDNODE;
u.s.Node = N;
@@ -62,14 +65,16 @@
// Constructor for constants.
SDDbgValue(MDNode *mdP, const Value *C, uint64_t off, DebugLoc dl,
unsigned O) :
- mdPtr(mdP), Offset(off), DL(dl), Order(O), Invalid(false) {
+ mdPtr(mdP), IsIndirect(false), Offset(off), DL(dl), Order(O),
+ Invalid(false) {
kind = CONST;
u.Const = C;
}
// Constructor for frame indices.
SDDbgValue(MDNode *mdP, unsigned FI, uint64_t off, DebugLoc dl, unsigned O) :
- mdPtr(mdP), Offset(off), DL(dl), Order(O), Invalid(false) {
+ mdPtr(mdP), IsIndirect(false), Offset(off), DL(dl), Order(O),
+ Invalid(false) {
kind = FRAMEIX;
u.FrameIx = FI;
}
@@ -92,6 +97,9 @@
// Returns the FrameIx for a stack object
unsigned getFrameIx() { assert (kind==FRAMEIX); return u.FrameIx; }
+ // Returns whether this is an indirect value.
+ bool isIndirect() { return IsIndirect; }
+
// Returns the offset.
uint64_t getOffset() { return Offset; }