Each input file is encoded as a separate compile unit in LLVM debugging

information output. However, many target specific tool chains prefer to encode
only one compile unit in an object file. In this situation, the LLVM code
generator will include  debugging information entities in the compile unit 
that is marked as main compile unit. The code generator accepts maximum one main
compile unit per module. If a module does not contain any main compile unit 
then the code generator will emit multiple compile units in the output object 
file.

[Part 1]

Update DebugInfo APIs to accept optional boolean value while creating DICompileUnit  to mark the unit as "main" unit. By defaults all units are considered  non-main.  Update SourceLevelDebugging.html to document "main" compile unit.

Update DebugInfo APIs to not accept and encode separate source file/directory entries while creating various llvm.dbg.* entities. There was a recent, yet to be documented, change to include this additional information so no documentation changes are required here.

Update DwarfDebug to handle "main" compile unit. If "main" compile unit is seen then all DIEs are inserted into "main" compile unit. All other compile units are used to find source location for llvm.dbg.* values. If there is not any "main" compile unit then create unique compile unit DIEs for each llvm.dbg.compile_unit.

[Part 2]

Create separate llvm.dbg.compile_unit for each input file. Mark compile unit create for main_input_filename as "main" compile unit. Use appropriate compile unit, based on source location information collected from the tree node, while creating llvm.dbg.* values using DebugInfo APIs.

---

This is Part 1.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63400 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 46 insertions, 0 deletions

diff --git a/test/DebugInfo/2009-01-29-HeaderLocation.ll b/test/DebugInfo/2009-01-29-HeaderLocation.ll
new file mode 100644
index 0000000000..c59a1c730c
--- /dev/null
+++ b/test/DebugInfo/2009-01-29-HeaderLocation.ll
@@ -0,0 +1,46 @@
+; RUN: llvm-as < %s | llc | grep "m.h" | count 1
+target triple = "i386-apple-darwin9.6"
+	%llvm.dbg.anchor.type = type { i32, i32 }
+	%llvm.dbg.basictype.type = type { i32, { }*, i8*, { }*, i32, i64, i64, i64, i32, i32 }
+	%llvm.dbg.compile_unit.type = type { i32, { }*, i32, i8*, i8*, i8*, i1, i1, i8* }
+	%llvm.dbg.composite.type = type { i32, { }*, i8*, { }*, i32, i64, i64, i64, i32, { }*, { }* }
+	%llvm.dbg.subprogram.type = type { i32, { }*, { }*, i8*, i8*, i8*, { }*, i32, { }*, i1, i1 }
+@llvm.dbg.compile_units = linkonce constant %llvm.dbg.anchor.type { i32 458752, i32 17 }, section "llvm.metadata"		; <%llvm.dbg.anchor.type*> [#uses=1]
+@.str = internal constant [4 x i8] c"m.c\00", section "llvm.metadata"		; <[4 x i8]*> [#uses=1]
+@.str1 = internal constant [26 x i8] c"/Volumes/Nanpura/dbg.test\00", section "llvm.metadata"		; <[26 x i8]*> [#uses=1]
+@.str2 = internal constant [52 x i8] c"4.2.1 (Based on Apple Inc. build 5636) (LLVM build)\00", section "llvm.metadata"		; <[52 x i8]*> [#uses=1]
+@llvm.dbg.compile_unit = internal constant %llvm.dbg.compile_unit.type { i32 458769, { }* bitcast (%llvm.dbg.anchor.type* @llvm.dbg.compile_units to { }*), i32 1, i8* getelementptr ([4 x i8]* @.str, i32 0, i32 0), i8* getelementptr ([26 x i8]* @.str1, i32 0, i32 0), i8* getelementptr ([52 x i8]* @.str2, i32 0, i32 0), i1 true, i1 false, i8* null }, section "llvm.metadata"		; <%llvm.dbg.compile_unit.type*> [#uses=1]
+@.str3 = internal constant [4 x i8] c"int\00", section "llvm.metadata"		; <[4 x i8]*> [#uses=1]
+@llvm.dbg.basictype = internal constant %llvm.dbg.basictype.type { i32 458788, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*), i8* getelementptr ([4 x i8]* @.str3, i32 0, i32 0), { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*), i32 0, i64 32, i64 32, i64 0, i32 0, i32 5 }, section "llvm.metadata"		; <%llvm.dbg.basictype.type*> [#uses=1]
+@llvm.dbg.array = internal constant [1 x { }*] [ { }* bitcast (%llvm.dbg.basictype.type* @llvm.dbg.basictype to { }*) ], section "llvm.metadata"		; <[1 x { }*]*> [#uses=1]
+@llvm.dbg.composite = internal constant %llvm.dbg.composite.type { i32 458773, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*), i8* null, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*), i32 0, i64 0, i64 0, i64 0, i32 0, { }* null, { }* bitcast ([1 x { }*]* @llvm.dbg.array to { }*) }, section "llvm.metadata"		; <%llvm.dbg.composite.type*> [#uses=1]
+@.str4 = internal constant [4 x i8] c"m.h\00", section "llvm.metadata"		; <[4 x i8]*> [#uses=1]
+@llvm.dbg.compile_unit5 = internal constant %llvm.dbg.compile_unit.type { i32 458769, { }* bitcast (%llvm.dbg.anchor.type* @llvm.dbg.compile_units to { }*), i32 1, i8* getelementptr ([4 x i8]* @.str4, i32 0, i32 0), i8* getelementptr ([26 x i8]* @.str1, i32 0, i32 0), i8* getelementptr ([52 x i8]* @.str2, i32 0, i32 0), i1 false, i1 false, i8* null }, section "llvm.metadata"		; <%llvm.dbg.compile_unit.type*> [#uses=1]
+@llvm.dbg.subprograms = linkonce constant %llvm.dbg.anchor.type { i32 458752, i32 46 }, section "llvm.metadata"		; <%llvm.dbg.anchor.type*> [#uses=1]
+@.str6 = internal constant [5 x i8] c"main\00", section "llvm.metadata"		; <[5 x i8]*> [#uses=1]
+@llvm.dbg.subprogram = internal constant %llvm.dbg.subprogram.type { i32 458798, { }* bitcast (%llvm.dbg.anchor.type* @llvm.dbg.subprograms to { }*), { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit to { }*), i8* getelementptr ([5 x i8]* @.str6, i32 0, i32 0), i8* getelementptr ([5 x i8]* @.str6, i32 0, i32 0), i8* null, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit5 to { }*), i32 2, { }* bitcast (%llvm.dbg.composite.type* @llvm.dbg.composite to { }*), i1 false, i1 true }, section "llvm.metadata"		; <%llvm.dbg.subprogram.type*> [#uses=1]
+
+define i32 @main() nounwind {
+entry:
+	%retval = alloca i32		; <i32*> [#uses=2]
+	%0 = alloca i32		; <i32*> [#uses=2]
+	%"alloca point" = bitcast i32 0 to i32		; <i32> [#uses=0]
+	call void @llvm.dbg.func.start({ }* bitcast (%llvm.dbg.subprogram.type* @llvm.dbg.subprogram to { }*))
+	call void @llvm.dbg.stoppoint(i32 2, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit5 to { }*))
+	store i32 0, i32* %0, align 4
+	%1 = load i32* %0, align 4		; <i32> [#uses=1]
+	store i32 %1, i32* %retval, align 4
+	br label %return
+
+return:		; preds = %entry
+	%retval1 = load i32* %retval		; <i32> [#uses=1]
+	call void @llvm.dbg.stoppoint(i32 2, i32 0, { }* bitcast (%llvm.dbg.compile_unit.type* @llvm.dbg.compile_unit5 to { }*))
+	call void @llvm.dbg.region.end({ }* bitcast (%llvm.dbg.subprogram.type* @llvm.dbg.subprogram to { }*))
+	ret i32 %retval1
+}
+
+declare void @llvm.dbg.func.start({ }*) nounwind
+
+declare void @llvm.dbg.stoppoint(i32, i32, { }*) nounwind
+
+declare void @llvm.dbg.region.end({ }*) nounwind