Skip zero column for inline sites

[wenlei]

Summary

D64033 added DW_AT_call_column for inline sites. However, that change wasn't aware of "-gno-column-info". To avoid adding column info when "-gno-column-info" is used, now DW_AT_call_column is only added when we have non-zero column (when "-gno-column-info" is used, column will be zero).

Test Plan:
ninja check

[dblaikie]

Test coverage? (you could add another inlined call to the test case you added for the feature - but just leave the inlined-at location with a zero column for that particular call - so you can still test both positive/negatiev in the one file)

[wenlei]

Tweak test case to add coverage for zero-coloumn inline site

[wenlei]

In D64784#1586900, @dblaikie wrote:

Test coverage? (you could add another inlined call to the test case you added for the feature - but just leave the inlined-at location with a zero column for that particular call - so you can still test both positive/negatiev in the one file)

Thanks! done.

[wenlei]

@dblaikie, thanks for review. Could you help land this change? I don't have commit permission yet..

llvm/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp

DIE *DwarfCompileUnit::constructInlinedScopeDIE(LexicalScope *Scope) {
 
   attachRangesOrLowHighPC(*ScopeDIE, Scope->getRanges());
 
   // Add the call site information to the DIE.
   const DILocation *IA = Scope->getInlinedAt();
   addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
           getOrCreateSourceID(IA->getFile()));
   addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, IA->getLine());
+  if (IA->getColumn())
     addUInt(*ScopeDIE, dwarf::DW_AT_call_column, None, IA->getColumn());
   if (IA->getDiscriminator() && DD->getDwarfVersion() >= 4)
     addUInt(*ScopeDIE, dwarf::DW_AT_GNU_discriminator, None,
             IA->getDiscriminator());
 
   // Add name to the name table, we do this here because we're guaranteed
   // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
   DD->addSubprogramNames(*CUNode, InlinedSP, *ScopeDIE);
 

llvm/test/DebugInfo/X86/fission-inline.ll

 ; CHECK-NOT: {{DW_|NULL}}
 ; CHECK:        DW_TAG_inlined_subroutine
 ; CHECK-NEXT:     DW_AT_abstract_origin {{.*}} "f2<int>"
 ; CHECK-NEXT:     DW_AT_ranges
 ; CHECK-NOT: {{DW_AT|DW_TAG|NULL}}
 ; CHECK:     DW_AT_call_file
 ; CHECK-NEXT:     DW_AT_call_line {{.*}} (18)
 ; CHECK-NEXT:     DW_AT_call_column {{.*}} (0x05)
+; CHECK:     DW_AT_call_file
+; CHECK-NEXT:     DW_AT_call_line {{.*}} (21)
 ; CHECK-NOT: DW_
 ; CHECK: .debug_info.dwo contents:
 
 ; RELOCS-NOT: RELOCATION RECORDS FOR [.rela.debug_ranges]
 
 ; Function Attrs: uwtable
 define void @_ZN3foo2f3Ez(...) #0 align 2 !dbg !10 {
 entry:
   call void @_Z2f1v(), !dbg !26
   call void @_Z2f1v(), !dbg !25
   call void @_Z2f1v(), !dbg !28
+  call void @_Z2f1v(), !dbg !29
   ret void, !dbg !29
 }
 
 declare void @_Z2f1v() #1
 
 attributes #0 = { 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 = { "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" }
 

 !21 = distinct !DILexicalBlock(line: 16, column: 7, file: !1, scope: !10)
 !22 = !{i32 2, !"Dwarf Version", i32 4}
 !23 = !{i32 2, !"Debug Info Version", i32 3}
 !24 = !{!"clang version 3.6.0 "}
 !25 = !DILocation(line: 17, column: 5, scope: !20)
 !26 = !DILocation(line: 11, column: 3, scope: !11, inlinedAt: !27)
 !27 = !DILocation(line: 18, column: 5, scope: !20)
 !28 = !DILocation(line: 12, column: 3, scope: !11, inlinedAt: !27)
-!29 = !DILocation(line: 21, column: 1, scope: !10)
+!29 = !DILocation(line: 12, column: 3, scope: !11, inlinedAt: !30)
+!30 = !DILocation(line: 21, column: 0, scope: !10)