Reapply DW_AT_low/high_pc patch:

    Use the range machinery for DW_AT_ranges and DW_AT_high/lo_pc.

    This commit moves us from a single range per subprogram to extending
    ranges if we are:

    a) In the same section, and
    b) In the same enclosing CU.

    This means we have more fine grained ranges for compile units, and fewer
    ranges overall when we have multiple functions in the same CU
    adjacent to each other in the object file.

    Also remove all of the earlier hacks around this functionality for
    function sections etc. Also update all of the testcases to take into
    account the merging functionality.

with a fix for location entries in the debug_loc section:

Make sure that debug loc entries are relative to the low_pc
of the compile unit. This means that when we only have a single
range that the offset should be just relative to the low_pc
of the unit, for multiple ranges for a CU this means that we'll be
relative to 0 which we emit along with DW_AT_ranges.

This mostly shows up with linked binaries, so add a testcase with
multiple CUs so that our location is going to be offset of a CU
with a non-zero low_pc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204377 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 18 deletions

diff --git a/test/DebugInfo/X86/low-pc-cu.ll b/test/DebugInfo/X86/low-pc-cu.ll
index 1d354c30d6..979d4006b9 100644
--- a/test/DebugInfo/X86/low-pc-cu.ll
+++ b/test/DebugInfo/X86/low-pc-cu.ll
@@ -5,28 +5,32 @@
 
 ; CHECK: DW_TAG_compile_unit [1]
 ; CHECK: DW_AT_low_pc [DW_FORM_addr]       (0x0000000000000000)
+; CHECK: DW_AT_high_pc [DW_FORM_data4]
 ; CHECK: DW_TAG_subprogram [2]
+; CHECK: DW_AT_low_pc [DW_FORM_addr]
+; CHECK: DW_AT_high_pc [DW_FORM_data4]
 
-define i32 @_Z1qv() nounwind uwtable readnone ssp {
+; Function Attrs: nounwind uwtable
+define void @z() #0 {
 entry:
-  ret i32 undef, !dbg !13
+  ret void, !dbg !11
 }
 
+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" }
+
 !llvm.dbg.cu = !{!0}
-!llvm.module.flags = !{!16}
+!llvm.module.flags = !{!8, !9}
+!llvm.ident = !{!10}
 
-!0 = metadata !{i32 786449, metadata !15, i32 4, metadata !"clang version 3.1 (trunk 153454) (llvm/trunk 153471)", i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !1,  metadata !1, metadata !""} ; [ DW_TAG_compile_unit ]
-!1 = metadata !{}
-!3 = metadata !{metadata !5, metadata !12}
-!5 = metadata !{i32 786478, metadata !6, null, metadata !"q", metadata !"q", metadata !"_Z1qv", i32 5, metadata !7, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 ()* @_Z1qv, null, null, metadata !10, i32 0} ; [ DW_TAG_subprogram ] [line 5] [def] [scope 0] [q]
-!6 = metadata !{i32 786473, metadata !15} ; [ DW_TAG_file_type ]
-!7 = metadata !{i32 786453, i32 0, null, i32 0, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !8, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
-!8 = metadata !{metadata !9}
-!9 = metadata !{i32 786468, metadata !15, null, metadata !"int", 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 !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, i32 0} ; [ 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"}
-!16 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!0 = metadata !{i32 786449, metadata !1, i32 12, metadata !"clang version 3.5.0 (trunk 204164) (llvm/trunk 204183)", i1 false, metadata !"", i32 0, metadata !2, metadata !2, metadata !3, metadata !2, metadata !2, metadata !"", i32 1} ; [ DW_TAG_compile_unit ] [/usr/local/google/home/echristo/z.c] [DW_LANG_C99]
+!1 = metadata !{metadata !"z.c", metadata !"/usr/local/google/home/echristo"}
+!2 = metadata !{}
+!3 = metadata !{metadata !4}
+!4 = metadata !{i32 786478, metadata !1, metadata !5, metadata !"z", metadata !"z", metadata !"", i32 1, metadata !6, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, void ()* @z, null, null, metadata !2, i32 1} ; [ DW_TAG_subprogram ] [line 1] [def] [z]
+!5 = metadata !{i32 786473, metadata !1}          ; [ DW_TAG_file_type ] [/usr/local/google/home/echristo/z.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 !{null}
+!8 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
+!9 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!10 = metadata !{metadata !"clang version 3.5.0 (trunk 204164) (llvm/trunk 204183)"}
+!11 = metadata !{i32 1, i32 0, metadata !4, null}