r181634 - PR14992: Debug Info: Support more non-type template parameters
David Blaikie
dblaikie at gmail.com
Fri May 10 14:53:14 PDT 2013
Author: dblaikie
Date: Fri May 10 16:53:14 2013
New Revision: 181634
URL: http://llvm.org/viewvc/llvm-project?rev=181634&view=rev
Log:
PR14992: Debug Info: Support more non-type template parameters
* Provide DW_TAG_template_value_parameter for pointers, function
pointers, member pointers, and member function pointers (still missing
support for template template parameters which GCC encodes as a
DW_TAG_GNU_template_template_param)
* Provide values for all but the (member & non-member) function pointer case.
Simple constant integer values for member pointers (offset within the
object) and address for the value pointer case. GCC doesn't provide a
value for the member function pointer case so I'm not sure how, if at
all, GDB supports encoding that. & non-member function pointers should
follow shortly in a subsequent patch.
* Null pointer value encodings of all of these types, including
correctly encoding null data member pointers as -1.
Modified:
cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
cfe/trunk/test/CodeGenCXX/debug-info-template.cpp
Modified: cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDebugInfo.cpp?rev=181634&r1=181633&r2=181634&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDebugInfo.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDebugInfo.cpp Fri May 10 16:53:14 2013
@@ -13,6 +13,7 @@
#include "CGDebugInfo.h"
#include "CGBlocks.h"
+#include "CGCXXABI.h"
#include "CGObjCRuntime.h"
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
@@ -1188,17 +1189,88 @@ CollectTemplateParams(const TemplatePara
for (unsigned i = 0, e = TAList.size(); i != e; ++i) {
const TemplateArgument &TA = TAList[i];
const NamedDecl *ND = TPList->getParam(i);
- if (TA.getKind() == TemplateArgument::Type) {
+ switch (TA.getKind()) {
+ case TemplateArgument::Type: {
llvm::DIType TTy = getOrCreateType(TA.getAsType(), Unit);
llvm::DITemplateTypeParameter TTP =
DBuilder.createTemplateTypeParameter(TheCU, ND->getName(), TTy);
TemplateParams.push_back(TTP);
- } else if (TA.getKind() == TemplateArgument::Integral) {
+ } break;
+ case TemplateArgument::Integral: {
llvm::DIType TTy = getOrCreateType(TA.getIntegralType(), Unit);
llvm::DITemplateValueParameter TVP =
- DBuilder.createTemplateValueParameter(TheCU, ND->getName(), TTy,
- TA.getAsIntegral().getZExtValue());
- TemplateParams.push_back(TVP);
+ DBuilder.createTemplateValueParameter(
+ TheCU, ND->getName(), TTy,
+ llvm::ConstantInt::get(CGM.getLLVMContext(), TA.getAsIntegral()));
+ TemplateParams.push_back(TVP);
+ } break;
+ case TemplateArgument::Declaration: {
+ const ValueDecl *D = TA.getAsDecl();
+ bool InstanceMember = D->isCXXInstanceMember();
+ QualType T = InstanceMember
+ ? CGM.getContext().getMemberPointerType(
+ D->getType(), cast<RecordDecl>(D->getDeclContext())
+ ->getTypeForDecl())
+ : CGM.getContext().getPointerType(D->getType());
+ llvm::DIType TTy = getOrCreateType(T, Unit);
+ llvm::Value *V = 0;
+ // Variable pointer template parameters have a value that is the address
+ // of the variable.
+ if (const VarDecl *VD = dyn_cast<VarDecl>(D))
+ V = CGM.GetAddrOfGlobalVar(VD);
+ // Member function pointers have special support for building them, though
+ // this is currently unsupported in LLVM CodeGen.
+ if (InstanceMember)
+ if (const CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(D))
+ V = CGM.getCXXABI().EmitMemberPointer(method);
+ // Member data pointers have special handling too to compute the fixed
+ // offset within the object.
+ if (isa<FieldDecl>(D)) {
+ // These five lines (& possibly the above member function pointer
+ // handling) might be able to be refactored to use similar code in
+ // CodeGenModule::getMemberPointerConstant
+ uint64_t fieldOffset = CGM.getContext().getFieldOffset(D);
+ CharUnits chars =
+ CGM.getContext().toCharUnitsFromBits((int64_t) fieldOffset);
+ V = CGM.getCXXABI().EmitMemberDataPointer(
+ cast<MemberPointerType>(T.getTypePtr()), chars);
+ }
+ llvm::DITemplateValueParameter TVP =
+ DBuilder.createTemplateValueParameter(TheCU, ND->getName(), TTy, V);
+ TemplateParams.push_back(TVP);
+ } break;
+ case TemplateArgument::NullPtr: {
+ QualType T = TA.getNullPtrType();
+ llvm::DIType TTy = getOrCreateType(T, Unit);
+ llvm::Value *V = 0;
+ // Special case member data pointer null values since they're actually -1
+ // instead of zero.
+ if (const MemberPointerType *MPT =
+ dyn_cast<MemberPointerType>(T.getTypePtr()))
+ // But treat member function pointers as simple zero integers because
+ // it's easier than having a special case in LLVM's CodeGen. If LLVM
+ // CodeGen grows handling for values of non-null member function
+ // pointers then perhaps we could remove this special case and rely on
+ // EmitNullMemberPointer for member function pointers.
+ if (MPT->isMemberDataPointer())
+ V = CGM.getCXXABI().EmitNullMemberPointer(MPT);
+ if (!V)
+ V = llvm::ConstantInt::get(CGM.Int8Ty, 0);
+ llvm::DITemplateValueParameter TVP =
+ DBuilder.createTemplateValueParameter(TheCU, ND->getName(), TTy, V);
+ TemplateParams.push_back(TVP);
+ } break;
+ case TemplateArgument::Template:
+ // We could support this with the GCC extension
+ // DW_TAG_GNU_template_template_param
+ break;
+ // these next 4 should never occur
+ case TemplateArgument::Expression:
+ case TemplateArgument::TemplateExpansion:
+ case TemplateArgument::Pack:
+ case TemplateArgument::Null:
+ llvm_unreachable(
+ "These argument types shouldn't exist in concrete types");
}
}
return DBuilder.getOrCreateArray(TemplateParams);
Modified: cfe/trunk/test/CodeGenCXX/debug-info-template.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/debug-info-template.cpp?rev=181634&r1=181633&r2=181634&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/debug-info-template.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/debug-info-template.cpp Fri May 10 16:53:14 2013
@@ -1,26 +1,69 @@
-// RUN: %clang_cc1 -emit-llvm -g %s -o - -std=c++11 | FileCheck %s
+// RUN: %clang -S -emit-llvm -target x86_64-unknown_unknown -g %s -o - -std=c++11 | FileCheck %s
// CHECK: [[INT:![0-9]*]] = {{.*}} ; [ DW_TAG_base_type ] [int]
// CHECK: metadata [[TCI:![0-9]*]], i32 0, i32 1, %class.TC* @tci, null} ; [ DW_TAG_variable ] [tci]
-// CHECK: [[TC:![0-9]*]] = {{.*}}, metadata [[TCARGS:![0-9]*]]} ; [ DW_TAG_class_type ] [TC<int, 2, &glb, &foo::e, &foo::f, nullptr>]
-// CHECK: [[TCARGS]] = metadata !{metadata [[TCARG1:![0-9]*]], metadata [[TCARG2:![0-9]*]]}
+// CHECK: [[TC:![0-9]*]] = {{.*}}, metadata [[TCARGS:![0-9]*]]} ; [ DW_TAG_class_type ] [TC<unsigned int, 2, &glb, &foo::e, &foo::f>]
+// CHECK: [[TCARGS]] = metadata !{metadata [[TCARG1:![0-9]*]], metadata [[TCARG2:![0-9]*]], metadata [[TCARG3:![0-9]*]], metadata [[TCARG4:![0-9]*]], metadata [[TCARG5:![0-9]*]]}
//
// We seem to be missing file/line/col info on template value parameters -
-// metadata supports it but it's not populated.
+// metadata supports it but it's not populated. GCC doesn't emit it either,
+// perhaps we should just drop it from the metadata.
//
-// CHECK: [[TCARG1]] = {{.*}}metadata !"T", metadata [[INT]], {{.*}} ; [ DW_TAG_template_type_parameter ]
-// CHECK: [[TCARG2]] = {{.*}}metadata !"", metadata [[UINT:![0-9]*]], i64 2, {{.*}} ; [ DW_TAG_template_value_parameter ]
-// CHECK: [[UINT]] = {{.*}} ; [ DW_TAG_base_type ] [unsigned int]
+// CHECK: [[TCARG1]] = {{.*}}metadata !"T", metadata [[UINT:![0-9]*]], {{.*}} ; [ DW_TAG_template_type_parameter ]
+// CHECK: [[UINT:![0-9]*]] = {{.*}} ; [ DW_TAG_base_type ] [unsigned int]
+// CHECK: [[TCARG2]] = {{.*}}metadata !"", metadata [[UINT:![0-9]*]], i32 2, {{.*}} ; [ DW_TAG_template_value_parameter ]
+// CHECK: [[TCARG3]] = {{.*}}metadata !"x", metadata [[INTPTR:![0-9]*]], i32* @glb, {{.*}} ; [ DW_TAG_template_value_parameter ]
+// CHECK: [[INTPTR]] = {{.*}}, metadata [[INT]]} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [from int]
+// CHECK: [[TCARG4]] = {{.*}}metadata !"a", metadata [[MEMINTPTR:![0-9]*]], i64 8, {{.*}} ; [ DW_TAG_template_value_parameter ]
+// CHECK: [[MEMINTPTR]] = {{.*}}, metadata [[FOO:![0-9]*]]} ; [ DW_TAG_ptr_to_member_type ] {{.*}}[from int]
+//
+// We could just emit a declaration of 'foo' here, rather than the entire
+// definition (same goes for any time we emit a member (function or data)
+// pointer type)
+// CHECK: [[FOO]] = {{.*}} ; [ DW_TAG_structure_type ] [foo]
+// CHECK: metadata !"f", metadata !"_ZN3foo1fEv", i32 {{[0-9]*}}, metadata [[FTYPE:![0-9]*]],
+// CHECK: [[FTYPE:![0-9]*]] = {{.*}}, metadata [[FARGS:![0-9]*]], i32 0, i32 0} ; [ DW_TAG_subroutine_type ]
+// CHECK: [[FARGS]] = metadata !{null, metadata [[FARG1:![0-9]*]]}
+// CHECK: [[FARG1]] = {{.*}} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [artificial] [from foo]
+//
+// Currently Clang emits the pointer-to-member-function value, but LLVM doesn't
+// use it (GCC doesn't emit a value for pointers to member functions either - so
+// it's not clear what, if any, format would be acceptable to GDB)
+//
+// CHECK: [[TCARG5]] = {{.*}}metadata !"b", metadata [[MEMFUNPTR:![0-9]*]], { i64, i64 } { i64 ptrtoint (void (%struct.foo*)* @_ZN3foo1fEv to i64), i64 0 }, {{.*}} ; [ DW_TAG_template_value_parameter ]
+// CHECK: [[MEMFUNPTR]] = {{.*}}, metadata [[FTYPE]], metadata [[FOO]]} ; [ DW_TAG_ptr_to_member_type ]
+
+// CHECK: metadata [[TCNT:![0-9]*]], i32 0, i32 1, %class.TC.0* @tcn, null} ; [ DW_TAG_variable ] [tcn]
+// CHECK: [[TCNT:![0-9]*]] = {{.*}}, metadata [[TCNARGS:![0-9]*]]} ; [ DW_TAG_class_type ] [TC<int, -3, nullptr, nullptr, nullptr>]
+// CHECK: [[TCNARGS]] = metadata !{metadata [[TCNARG1:![0-9]*]], metadata [[TCNARG2:![0-9]*]], metadata [[TCNARG3:![0-9]*]], metadata [[TCNARG4:![0-9]*]], metadata [[TCNARG5:![0-9]*]]}
+// CHECK: [[TCNARG1]] = {{.*}}metadata !"T", metadata [[INT]], {{.*}} ; [ DW_TAG_template_type_parameter ]
+// CHECK: [[TCNARG2]] = {{.*}}metadata !"", metadata [[INT]], i32 -3, {{.*}} ; [ DW_TAG_template_value_parameter ]
+// CHECK: [[TCNARG3]] = {{.*}}metadata !"x", metadata [[INTPTR]], i8 0, {{.*}} ; [ DW_TAG_template_value_parameter ]
+
+// The interesting null pointer: -1 for member data pointers (since they are
+// just an offset in an object, they can be zero and non-null for the first
+// member)
+
+// CHECK: [[TCNARG4]] = {{.*}}metadata !"a", metadata [[MEMINTPTR]], i64 -1, {{.*}} ; [ DW_TAG_template_value_parameter ]
+//
+// In some future iteration we could possibly emit the value of a null member
+// function pointer as '{ i64, i64 } zeroinitializer' as it may be handled
+// naturally from the LLVM CodeGen side once we decide how to handle non-null
+// member function pointers. For now, it's simpler just to emit the 'i8 0'.
+//
+// CHECK: [[TCNARG5]] = {{.*}}metadata !"b", metadata [[MEMFUNPTR:![0-9]*]], i8 0, {{.*}} ; [ DW_TAG_template_value_parameter ]
struct foo {
+ char pad[8]; // make the member pointer to 'e' a bit more interesting (nonzero)
int e;
void f();
};
-template<typename T, unsigned, int *x, int foo::*a, void (foo::*b)(), int *n>
+template<typename T, T, int *x, int foo::*a, void (foo::*b)()>
class TC {
};
int glb;
-TC<int, 2, &glb, &foo::e, &foo::f, nullptr> tci;
+TC<unsigned, 2, &glb, &foo::e, &foo::f> tci;
+TC<int, -3, nullptr, nullptr, nullptr> tcn;
More information about the cfe-commits
mailing list