Add support for DW_TAG_thrown_type.
For Swift we would like to be able to encode the error types that a
function may throw, so the debugger can display them alongside the
function's return value when finish-ing a function.
DWARF defines DW_TAG_thrown_type (intended to be used for C++ throw()
declarations) that is a perfect fit for this purpose. This patch wires
up support for DW_TAG_thrown_type in LLVM by adding a list of thrown
types to DISubprogram.
To offset the cost of the extra pointer, there is a follow-up patch
that turns DISubprogram into a variable-length node.
rdar://problem/29481673
Differential Revision: https://reviews.llvm.org/D32559
llvm-svn: 301489
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
index 16fb20d..f2e1399 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp
@@ -662,6 +662,14 @@
}
}
+/// Add thrown types.
+void DwarfUnit::addThrownTypes(DIE &Die, DINodeArray ThrownTypes) {
+ for (const auto *Ty : ThrownTypes) {
+ DIE &TT = createAndAddDIE(dwarf::DW_TAG_thrown_type, Die);
+ addType(TT, cast<DIType>(Ty));
+ }
+}
+
DIE *DwarfUnit::getOrCreateContextDIE(const DIScope *Context) {
if (!Context || isa<DIFile>(Context))
return &getUnitDie();
@@ -1249,6 +1257,8 @@
constructSubprogramArguments(SPDie, Args);
}
+ addThrownTypes(SPDie, SP->getThrownTypes());
+
if (SP->isArtificial())
addFlag(SPDie, dwarf::DW_AT_artificial);
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
index e84df46..3bf4979 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfUnit.h
@@ -230,6 +230,9 @@
/// Add template parameters in buffer.
void addTemplateParams(DIE &Buffer, DINodeArray TParams);
+ /// Add thrown types.
+ void addThrownTypes(DIE &Die, DINodeArray ThrownTypes);
+
// FIXME: Should be reformulated in terms of addComplexAddress.
/// Start with the address based on the location provided, and generate the
/// DWARF information necessary to find the actual Block variable (navigating