Solidify the assumption that a DW_TAG_subprogram's type is a DW_TAG_subroutine_type

There were bits & pieces of code lying around that may've given the
impression that debug info metadata supported the possibility that a
subprogram's type could be specified by a non-subroutine type describing
the return type of a void function. This support was incomplete &
unnecessary. Asserts & API have been changed to make the desired usage
more clear.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182532 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/DIBuilder.h b/include/llvm/DIBuilder.h
index 906e9d4db5baa032149bd0a6c1cba8d1a3caa483..9352f674874fe44a893569288cab51c210587c54 100644 (file)
--- a/include/llvm/DIBuilder.h
+++ b/include/llvm/DIBuilder.h
@@ -505,7 +505,7 @@ namespace llvm {
     DISubprogram createFunction(DIDescriptor Scope, StringRef Name,
                                 StringRef LinkageName,
                                 DIFile File, unsigned LineNo,
-                                DIType Ty, bool isLocalToUnit,
+                                DICompositeType Ty, bool isLocalToUnit,
                                 bool isDefinition,
                                 unsigned ScopeLine,
                                 unsigned Flags = 0,
@@ -536,7 +536,7 @@ namespace llvm {
     DISubprogram createMethod(DIDescriptor Scope, StringRef Name,
                               StringRef LinkageName,
                               DIFile File, unsigned LineNo,
-                              DIType Ty, bool isLocalToUnit,
+                              DICompositeType Ty, bool isLocalToUnit,
                               bool isDefinition,
                               unsigned Virtuality = 0, unsigned VTableIndex = 0,
                               MDNode *VTableHolder = 0,

diff --git a/include/llvm/DebugInfo.h b/include/llvm/DebugInfo.h
index a4330070dcd7f77c91d53e13699f4f7f16ea201f..cc4352f27a194bb7a701c24d800f4fa32c32fe05 100644 (file)
--- a/include/llvm/DebugInfo.h
+++ b/include/llvm/DebugInfo.h
@@ -427,19 +427,6 @@ namespace llvm {
     unsigned getLineNumber() const      { return getUnsignedField(6); }
     DICompositeType getType() const { return getFieldAs<DICompositeType>(7); }
 
-    /// getReturnTypeName - Subprogram return types are encoded either as
-    /// DIType or as DICompositeType.
-    StringRef getReturnTypeName() const {
-      DICompositeType DCT(getFieldAs<DICompositeType>(7));
-      if (DCT.Verify()) {
-        DIArray A = DCT.getTypeArray();
-        DIType T(A.getElement(0));
-        return T.getName();
-      }
-      DIType T(getFieldAs<DIType>(7));
-      return T.getName();
-    }
-
     /// isLocalToUnit - Return true if this subprogram is local to the current
     /// compile unit, like 'static' in C.
     unsigned isLocalToUnit() const     { return getUnsignedField(8); }

diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index 7f0c33bb05c57e9b764d8863a6fc62729ef0f927..90ca034c976ab3709012c218f50411261a3f446d 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -1208,13 +1208,11 @@ DIE *CompileUnit::getOrCreateSubprogramDIE(DISubprogram SP) {
 
   // Add Return Type.
   DICompositeType SPTy = SP.getType();
-  DIArray Args = SPTy.getTypeArray();
-  unsigned SPTag = SPTy.getTag();
+  assert(SPTy.getTag() == dwarf::DW_TAG_subroutine_type &&
+         "the type of a subprogram should be a subroutine");
 
-  if (Args.getNumElements() == 0 || SPTag != dwarf::DW_TAG_subroutine_type)
-    addType(SPDie, SPTy);
-  else
-    addType(SPDie, DIType(Args.getElement(0)));
+  DIArray Args = SPTy.getTypeArray();
+  addType(SPDie, DIType(Args.getElement(0)));
 
   unsigned VK = SP.getVirtuality();
   if (VK) {
@@ -1232,19 +1230,14 @@ DIE *CompileUnit::getOrCreateSubprogramDIE(DISubprogram SP) {
 
     // Add arguments. Do not add arguments for subprogram definition. They will
     // be handled while processing variables.
-    DICompositeType SPTy = SP.getType();
-    DIArray Args = SPTy.getTypeArray();
-    unsigned SPTag = SPTy.getTag();
-
-    if (SPTag == dwarf::DW_TAG_subroutine_type)
-      for (unsigned i = 1, N =  Args.getNumElements(); i < N; ++i) {
-        DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter);
-        DIType ATy = DIType(Args.getElement(i));
-        addType(Arg, ATy);
-        if (ATy.isArtificial())
-          addFlag(Arg, dwarf::DW_AT_artificial);
-        SPDie->addChild(Arg);
-      }
+    for (unsigned i = 1, N =  Args.getNumElements(); i < N; ++i) {
+      DIE *Arg = new DIE(dwarf::DW_TAG_formal_parameter);
+      DIType ATy = DIType(Args.getElement(i));
+      addType(Arg, ATy);
+      if (ATy.isArtificial())
+        addFlag(Arg, dwarf::DW_AT_artificial);
+      SPDie->addChild(Arg);
+    }
   }
 
   if (SP.isArtificial())

diff --git a/lib/IR/DIBuilder.cpp b/lib/IR/DIBuilder.cpp
index 1c799452754e97caf4743cc724efc0f367a5f1e3..8edc6a0f10cb35ce7eb7eadcb93bba4cd65f4da4 100644 (file)
--- a/lib/IR/DIBuilder.cpp
+++ b/lib/IR/DIBuilder.cpp
@@ -969,13 +969,15 @@ DISubprogram DIBuilder::createFunction(DIDescriptor Context,
                                        StringRef Name,
                                        StringRef LinkageName,
                                        DIFile File, unsigned LineNo,
-                                       DIType Ty,
+                                       DICompositeType Ty,
                                        bool isLocalToUnit, bool isDefinition,
                                        unsigned ScopeLine,
                                        unsigned Flags, bool isOptimized,
                                        Function *Fn,
                                        MDNode *TParams,
                                        MDNode *Decl) {
+  assert(Ty.getTag() == dwarf::DW_TAG_subroutine_type &&
+         "function types should be subroutines");
   Value *TElts[] = { GetTagConstant(VMContext, DW_TAG_base_type) };
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_subprogram),
@@ -1014,7 +1016,7 @@ DISubprogram DIBuilder::createMethod(DIDescriptor Context,
                                      StringRef Name,
                                      StringRef LinkageName,
                                      DIFile F,
-                                     unsigned LineNo, DIType Ty,
+                                     unsigned LineNo, DICompositeType Ty,
                                      bool isLocalToUnit,
                                      bool isDefinition,
                                      unsigned VK, unsigned VIndex,
@@ -1023,6 +1025,8 @@ DISubprogram DIBuilder::createMethod(DIDescriptor Context,
                                      bool isOptimized,
                                      Function *Fn,
                                      MDNode *TParam) {
+  assert(Ty.getTag() == dwarf::DW_TAG_subroutine_type &&
+         "function types should be subroutines");
   Value *TElts[] = { GetTagConstant(VMContext, DW_TAG_base_type) };
   Value *Elts[] = {
     GetTagConstant(VMContext, dwarf::DW_TAG_subprogram),

diff --git a/test/DebugInfo/X86/low-pc-cu.ll b/test/DebugInfo/X86/low-pc-cu.ll
index 77f69b9617531935751ffa81b40a2602f08b3420..c080555193a1fb84f61019ead79c23a2d4b9547f 100644 (file)
--- a/test/DebugInfo/X86/low-pc-cu.ll
+++ b/test/DebugInfo/X86/low-pc-cu.ll
@@ -18,12 +18,13 @@ entry:
 !1 = metadata !{i32 0}
 !3 = metadata !{metadata !5, metadata !12}
 !5 = metadata !{i32 786478, metadata !"_Z1qv", i32 0, metadata !6, metadata !"q", metadata !"q", metadata !6, i32 5, metadata !7, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 ()* @_Z1qv, null, null, metadata !10} ; [ DW_TAG_subprogram ]
-!6 = metadata !{i32 786473, metadata !"foo.cpp", metadata !"/Users/echristo/tmp", null} ; [ DW_TAG_file_type ]
+!6 = metadata !{i32 786473, metadata !15} ; [ DW_TAG_file_type ]
 !7 = metadata !{i32 786453, i32 0, metadata !"", i32 0, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !8, i32 0, i32 0} ; [ DW_TAG_subroutine_type ]
 !8 = metadata !{metadata !9}
 !9 = metadata !{i32 786468, null, metadata !"int", null, i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ]
 !10 = metadata !{metadata !11}
 !11 = metadata !{i32 786468}                      ; [ DW_TAG_base_type ]
-!12 = metadata !{i32 786478, metadata !"", i32 0, metadata !6, metadata !"t", metadata !"t", metadata !6, i32 2, metadata !7, i1 true, i1 true, i32 0, i32 0, null, i32 256, i1 false, null, null, null, metadata !10} ; [ DW_TAG_subprogram ]
+!12 = metadata !{i32 786478, metadata !15, metadata !6, metadata !"t", metadata !"t", metadata !"", i32 2, metadata !7, i1 true, i1 true, i32 0, i32 0, null, i32 256, i1 false, null, null, null, metadata !10} ; [ DW_TAG_subprogram ]
 !13 = metadata !{i32 7, i32 1, metadata !14, null}
 !14 = metadata !{i32 786443, metadata !5, i32 5, i32 1, metadata !6, i32 0} ; [ DW_TAG_lexical_block ]
+!15 = metadata !{metadata !"foo.cpp", metadata !"/Users/echristo/tmp"}