[llvm] r203969 - If we see that we're emitting code for a function that doesn't have

[Eric Christopher]

Author: echristo
Date: Fri Mar 14 15:53:49 2014
New Revision: 203969

URL: http://llvm.org/viewvc/llvm-project?rev=203969&view=rev
Log:
If we see that we're emitting code for a function that doesn't have
any lexical scopes then go ahead and turn on DW_AT_ranges for the
compile unit since we would be claiming to describe in the CU
a range for which we don't have information in the CU otherwise.

Added:
    llvm/trunk/test/DebugInfo/cu-range-hole.ll
Modified:
    llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp

Modified: llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp?rev=203969&r1=203968&r2=203969&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/DwarfDebug.cpp Fri Mar 14 15:53:49 2014
@@ -1462,8 +1462,10 @@ void DwarfDebug::beginFunction(const Mac
   // Grab the lexical scopes for the function, if we don't have any of those
   // then we're not going to be able to do anything.
   LScopes.initialize(*MF);
-  if (LScopes.empty())
+  if (LScopes.empty()) {
+    UsedNonDefaultText = true;
     return;
+  }
 
   assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned");
 

Added: llvm/trunk/test/DebugInfo/cu-range-hole.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/DebugInfo/cu-range-hole.ll?rev=203969&view=auto
==============================================================================
--- llvm/trunk/test/DebugInfo/cu-range-hole.ll (added)
+++ llvm/trunk/test/DebugInfo/cu-range-hole.ll Fri Mar 14 15:53:49 2014
@@ -0,0 +1,56 @@
+; REQUIRES: object-emission
+; RUN: %llc_dwarf -O0 -filetype=obj %s -o %t
+; RUN: llvm-dwarfdump %t | FileCheck %s
+
+; Check that we emit ranges for this CU since we have a function with and
+; without debug info.
+; CHECK: DW_TAG_compile_unit
+; CHECK: DW_AT_ranges
+; CHECK: DW_TAG_subprogram
+
+; Function Attrs: nounwind uwtable
+define i32 @foo(i32 %a) #0 {
+entry:
+  %a.addr = alloca i32, align 4
+  store i32 %a, i32* %a.addr, align 4
+  call void @llvm.dbg.declare(metadata !{i32* %a.addr}, metadata !12), !dbg !13
+  %0 = load i32* %a.addr, align 4, !dbg !14
+  %add = add nsw i32 %0, 5, !dbg !14
+  ret i32 %add, !dbg !14
+}
+
+; Function Attrs: nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata) #1
+
+; Function Attrs: nounwind uwtable
+define i32 @bar(i32 %b) #0 {
+entry:
+  %b.addr = alloca i32, align 4
+  store i32 %b, i32* %b.addr, align 4
+  %0 = load i32* %b.addr, align 4
+  %add = add nsw i32 %0, 1
+  ret i32 %add
+}
+
+attributes #0 = { nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nounwind readnone }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!9, !10}
+!llvm.ident = !{!11, !11}
+
+!0 = metadata !{i32 786449, metadata !1, i32 12, metadata !"clang version 3.5.0 (trunk 203945) (llvm/trunk 203946)", i1 false, metadata !"", i32 0, metadata !2, metadata !2, metadata !3, metadata !2, metadata !2, metadata !"", i32 1}
+!1 = metadata !{metadata !"foo.c", metadata !"/usr/local/google/home/echristo"}
+!2 = metadata !{}
+!3 = metadata !{metadata !4}
+!4 = metadata !{i32 786478, metadata !1, metadata !5, metadata !"foo", metadata !"foo", metadata !"", i32 1, metadata !6, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 (i32)* @foo, null, null, metadata !2, i32 1} ; [ DW_TAG_subprogram ] [line 1] [def] [foo]
+!5 = metadata !{i32 786473, metadata !1}          ; [ DW_TAG_file_type ] [/usr/local/google/home/echristo/foo.c]
+!6 = metadata !{i32 786453, i32 0, null, metadata !"", i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !7, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
+!7 = metadata !{metadata !8, metadata !8}
+!8 = metadata !{i32 786468, null, null, metadata !"int", i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
+!9 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
+!10 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!11 = metadata !{metadata !"clang version 3.5.0 (trunk 203945) (llvm/trunk 203946)"}
+!12 = metadata !{i32 786689, metadata !4, metadata !"a", metadata !5, i32 16777217, metadata !8, i32 0, i32 0} ; [ DW_TAG_arg_variable ] [a] [line 1]
+!13 = metadata !{i32 1, i32 0, metadata !4, null}
+!14 = metadata !{i32 2, i32 0, metadata !4, null}