[DebugInfo] Fix emitting DWARF64 .debug_rnglists sections (13/19).

[ikudrin]

Summary

The size of the offsets in the table depends on the DWARF format.

[dblaikie]

Looks good, except possible test tidyup.

llvm/test/DebugInfo/X86/split-dwarf-v5-ranges.ll

24–31

Could you use https://llvm.org/docs/CommandGuide/FileCheck.html#filecheck-numeric-substitution-blocks to make these offsets relative to the offset in the offsets list, so they don't have to be duplicated for DWARF32/DWARF64?

[ikudrin]

• Updated the test as suggested. Thanks!

llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp

static MCSymbol *emitRnglistsTableHeader(AsmPrinter *Asm,
                                          const DwarfFile &Holder) {
   MCSymbol *TableEnd = mcdwarf::emitListsTableHeaderStart(*Asm->OutStreamer);
 
   Asm->OutStreamer->AddComment("Offset entry count");
   Asm->emitInt32(Holder.getRangeLists().size());
   Asm->OutStreamer->emitLabel(Holder.getRnglistsTableBaseSym());
 
   for (const RangeSpanList &List : Holder.getRangeLists())
-    Asm->emitLabelDifference(List.Label, Holder.getRnglistsTableBaseSym(), 4);
+    Asm->emitLabelDifference(List.Label, Holder.getRnglistsTableBaseSym(),
+                             Asm->getDwarfOffsetByteSize());
 
   return TableEnd;
 }
 
 // Emit the header of a DWARF 5 locations list table. Returns the symbol that
 // designates the end of the table for the caller to emit when the table is
 // complete.
 static MCSymbol *emitLoclistsTableHeader(AsmPrinter *Asm,

llvm/test/DebugInfo/X86/split-dwarf-v5-ranges.ll

-; RUN: llc -split-dwarf-file=foo.dwo -mtriple=x86_64-unknown-linux-gnu -filetype=obj < %s \
-; RUN:      | llvm-dwarfdump -v -debug-info -debug-rnglists - | FileCheck %s
+; RUN: llc -split-dwarf-file=foo.dwo -mtriple=x86_64-unknown-linux-gnu -filetype=obj %s -o %t32
+; RUN: llvm-dwarfdump -v -debug-info -debug-rnglists %t32 | \
+; RUN:   FileCheck %s --check-prefixes=CHECK,DWARF32
+
+; RUN: llc -dwarf64 -split-dwarf-file=foo.dwo -mtriple=x86_64-unknown-linux-gnu -filetype=obj %s -o %t64
+; RUN: llvm-dwarfdump -v -debug-info -debug-rnglists %t64 | \
+; RUN:   FileCheck %s --check-prefixes=CHECK,DWARF64
 
-; CHECK: .debug_info contents:
-; CHECK: .debug_info.dwo contents:
-; CHECK: DW_AT_ranges [DW_FORM_rnglistx] (indexed (0x0) rangelist = 0x00000010
-; CHECK:          [0x0000000000000001, 0x000000000000000c) ".text"
-; CHECK:          [0x000000000000000e, 0x0000000000000013) ".text")
+; CHECK:   .debug_info contents:
+; CHECK:   .debug_info.dwo contents:
+; CHECK:   DW_AT_ranges [DW_FORM_rnglistx] (indexed (0x0) rangelist = 0x[[#%.8x,RNG_OFF:]]
+; CHECK:      [0x0000000000000001, 0x000000000000000c) ".text"
+; CHECK:      [0x000000000000000e, 0x0000000000000013) ".text")
 
-; CHECK: .debug_rnglists.dwo contents:
-; CHECK: 0x00000000: range list header: length = 0x00000015, format = DWARF32, version = 0x0005, addr_size = 0x08, seg_size = 0x00, offset_entry_count = 0x00000001
-; CHECK: offsets: [
-; CHECK: 0x00000004 => 0x00000010
-; CHECK: ]
-; CHECK: ranges:
-; CHECK: 0x00000010: [DW_RLE_base_addressx]:  0x0000000000000000
-; CHECK: 0x00000012: [DW_RLE_offset_pair  ]:  0x0000000000000001, 0x000000000000000c => [0x0000000000000001, 0x000000000000000c)
-; CHECK: 0x00000015: [DW_RLE_offset_pair  ]:  0x000000000000000e, 0x0000000000000013 => [0x000000000000000e, 0x0000000000000013)
-; CHECK: 0x00000018: [DW_RLE_end_of_list  ]
+; CHECK:   .debug_rnglists.dwo contents:
+; DWARF32: 0x00000000: range list header: length = 0x00000015, format = DWARF32, version = 0x0005, addr_size = 0x08, seg_size = 0x00, offset_entry_count = 0x00000001
+; DWARF64: 0x00000000: range list header: length = 0x0000000000000019, format = DWARF64, version = 0x0005, addr_size = 0x08, seg_size = 0x00, offset_entry_count = 0x00000001
+; CHECK:   offsets: [
+; DWARF32: 0x00000004 => 0x[[#RNG_OFF]]
+; DWARF64: 0x0000000000000008 => 0x[[#RNG_OFF]]
+; CHECK:   ]
+; CHECK:   ranges:
+; CHECK:   0x[[#RNG_OFF]]:   [DW_RLE_base_addressx]:  0x0000000000000000
+; CHECK:   0x[[#RNG_OFF+2]]: [DW_RLE_offset_pair  ]:  0x0000000000000001, 0x000000000000000c => [0x0000000000000001, 0x000000000000000c)
+; CHECK:   0x[[#RNG_OFF+5]]: [DW_RLE_offset_pair  ]:  0x000000000000000e, 0x0000000000000013 => [0x000000000000000e, 0x0000000000000013)
+; CHECK:   0x[[#RNG_OFF+8]]: [DW_RLE_end_of_list  ]
 
 ; Function Attrs: noinline optnone uwtable
 define dso_local void @_Z2f3v() !dbg !7 {
 entry:
   %x = alloca i32, align 4
   call void @llvm.dbg.declare(metadata i32* %x, metadata !10, metadata !DIExpression()), !dbg !13
   %call = call i32 @_Z2f2v(), !dbg !14
   store i32 %call, i32* %x, align 4, !dbg !13
   %0 = load i32, i32* %x, align 4, !dbg !13
   %tobool = icmp ne i32 %0, 0, !dbg !13
   br i1 %tobool, label %if.then, label %if.end, !dbg !15
 
 if.then:                                          ; preds = %entry