[DebugInfo] - Fix for lld DWARF parsing of base address selection entries in range...

It solves issue of wrong section index evaluating for ranges when
base address is used.

Based on David Blaikie's patch D36097.

Differential revision: https://reviews.llvm.org/D37214

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312477 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h b/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h
index bcba14b1630d1e24a78187b510a2b8986fa598c4..421b6a4b561eba6ff10a88f0544df22687a9e1fe 100644 (file)
--- a/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h
+++ b/include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h
@@ -18,6 +18,7 @@
 
 namespace llvm {
 
+struct BaseAddress;
 class raw_ostream;
 
 struct DWARFAddressRange {
@@ -85,7 +86,8 @@ public:
   /// getAbsoluteRanges - Returns absolute address ranges defined by this range
   /// list. Has to be passed base address of the compile unit referencing this
   /// range list.
-  DWARFAddressRangesVector getAbsoluteRanges(uint64_t BaseAddress) const;
+  DWARFAddressRangesVector
+  getAbsoluteRanges(llvm::Optional<BaseAddress> BaseAddr) const;
 };
 
 } // end namespace llvm

diff --git a/include/llvm/DebugInfo/DWARF/DWARFUnit.h b/include/llvm/DebugInfo/DWARF/DWARFUnit.h
index c39fc4c974436a59bb586b3fbfb16e830efc2b88..6e85e71e5b34ca219962aede36e937af648967b4 100644 (file)
--- a/include/llvm/DebugInfo/DWARF/DWARFUnit.h
+++ b/include/llvm/DebugInfo/DWARF/DWARFUnit.h
@@ -110,6 +110,12 @@ private:
   }
 };
 
+/// Represents base address of the CU.
+struct BaseAddress {
+  uint64_t Address;
+  uint64_t SectionIndex;
+};
+
 class DWARFUnit {
   DWARFContext &Context;
   /// Section containing this DWARFUnit.
@@ -135,7 +141,7 @@ class DWARFUnit {
   uint32_t Length;
   const DWARFAbbreviationDeclarationSet *Abbrevs;
   uint8_t UnitType;
-  uint64_t BaseAddr;
+  llvm::Optional<BaseAddress> BaseAddr;
   /// The compile unit debug information entry items.
   std::vector<DWARFDebugInfoEntry> DieArray;
 
@@ -259,11 +265,9 @@ public:
     llvm_unreachable("Invalid UnitType.");
   }
 
-  uint64_t getBaseAddress() const { return BaseAddr; }
+  llvm::Optional<BaseAddress> getBaseAddress() const { return BaseAddr; }
 
-  void setBaseAddress(uint64_t base_addr) {
-    BaseAddr = base_addr;
-  }
+  void setBaseAddress(BaseAddress BaseAddr) { this->BaseAddr = BaseAddr; }
 
   DWARFDie getUnitDIE(bool ExtractUnitDIEOnly = true) {
     extractDIEsIfNeeded(ExtractUnitDIEOnly);

diff --git a/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp b/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp
index a40635568cdddcb1695ee52c9de335907669ecee..861dd313fb095d48a0e9cb38fcb1745dc7ef3e73 100644 (file)
--- a/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp
+++ b/lib/DebugInfo/DWARF/DWARFDataExtractor.cpp
@@ -14,6 +14,8 @@ using namespace llvm;
 
 uint64_t DWARFDataExtractor::getRelocatedValue(uint32_t Size, uint32_t *Off,
                                                uint64_t *SecNdx) const {
+  if (SecNdx)
+    *SecNdx = -1ULL;
   if (!Section)
     return getUnsigned(Off, Size);
   Optional<RelocAddrEntry> Rel = Obj->find(*Section, *Off);

diff --git a/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp b/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp
index aa1f17934b5969e7788848c59dc0621a08b8010c..62bd5af4e649924a3820e2e0edcce6db786408bf 100644 (file)
--- a/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp
+++ b/lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp
@@ -63,16 +63,29 @@ void DWARFDebugRangeList::dump(raw_ostream &OS) const {
   OS << format("%08x <End of list>\n", Offset);
 }
 
-DWARFAddressRangesVector
-DWARFDebugRangeList::getAbsoluteRanges(uint64_t BaseAddress) const {
+DWARFAddressRangesVector DWARFDebugRangeList::getAbsoluteRanges(
+    llvm::Optional<BaseAddress> BaseAddr) const {
   DWARFAddressRangesVector Res;
   for (const RangeListEntry &RLE : Entries) {
     if (RLE.isBaseAddressSelectionEntry(AddressSize)) {
-      BaseAddress = RLE.EndAddress;
-    } else {
-      Res.push_back({BaseAddress + RLE.StartAddress,
-                     BaseAddress + RLE.EndAddress, RLE.SectionIndex});
+      BaseAddr = {RLE.EndAddress, RLE.SectionIndex};
+      continue;
     }
+
+    DWARFAddressRange E;
+    E.LowPC = RLE.StartAddress;
+    E.HighPC = RLE.EndAddress;
+    E.SectionIndex = RLE.SectionIndex;
+    // Base address of a range list entry is determined by the closest preceding
+    // base address selection entry in the same range list. It defaults to the
+    // base address of the compilation unit if there is no such entry.
+    if (BaseAddr) {
+      E.LowPC += BaseAddr->Address;
+      E.HighPC += BaseAddr->Address;
+      if (E.SectionIndex == -1ULL)
+        E.SectionIndex = BaseAddr->SectionIndex;
+    }
+    Res.push_back(E);
   }
   return Res;
 }

diff --git a/lib/DebugInfo/DWARF/DWARFUnit.cpp b/lib/DebugInfo/DWARF/DWARFUnit.cpp
index 5b0b3f65f6c30639cba6578479dbee25ef438805..813960ca95d783e5ebcf45f0c66a8ee2449462d6 100644 (file)
--- a/lib/DebugInfo/DWARF/DWARFUnit.cpp
+++ b/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -160,7 +160,7 @@ void DWARFUnit::clear() {
   Length = 0;
   Abbrevs = nullptr;
   FormParams = DWARFFormParams({0, 0, DWARF32});
-  BaseAddr = 0;
+  BaseAddr.reset();
   RangeSectionBase = 0;
   AddrOffsetSectionBase = 0;
   clearDIEs(false);
@@ -242,9 +242,10 @@ size_t DWARFUnit::extractDIEsIfNeeded(bool CUDieOnly) {
   // If CU DIE was just parsed, copy several attribute values from it.
   if (!HasCUDie) {
     DWARFDie UnitDie = getUnitDIE();
-    auto BaseAddr = toAddress(UnitDie.find({DW_AT_low_pc, DW_AT_entry_pc}));
-    if (BaseAddr)
-      setBaseAddress(*BaseAddr);
+    Optional<DWARFFormValue> PC = UnitDie.find({DW_AT_low_pc, DW_AT_entry_pc});
+    if (Optional<uint64_t> Addr = toAddress(PC))
+        setBaseAddress({*Addr, PC->getSectionIndex()});
+
     if (!isDWO) {
       assert(AddrOffsetSectionBase == 0);
       assert(RangeSectionBase == 0);

diff --git a/test/DebugInfo/Inputs/dwarfdump-ranges-baseaddr-exe.elf-x86-64 b/test/DebugInfo/Inputs/dwarfdump-ranges-baseaddr-exe.elf-x86-64
new file mode 100644 (file)
index 0000000..ab9960b
Binary files /dev/null and b/test/DebugInfo/Inputs/dwarfdump-ranges-baseaddr-exe.elf-x86-64 differ

diff --git a/test/DebugInfo/X86/dwarfdump-ranges-baseaddr-exe.s b/test/DebugInfo/X86/dwarfdump-ranges-baseaddr-exe.s
new file mode 100644 (file)
index 0000000..64f7009
--- /dev/null
+++ b/test/DebugInfo/X86/dwarfdump-ranges-baseaddr-exe.s
@@ -0,0 +1,13 @@
+# RUN: llvm-dwarfdump %S/../Inputs/dwarfdump-ranges-baseaddr-exe.elf-x86-64 \
+# RUN:  | FileCheck %s
+
+## Executable binary for test produced from object built in 
+## dwarfdump-ranges-baseaddr.s testcase.
+
+# CHECK: .debug_info contents:
+# CHECK: 0x0000000b: DW_TAG_compile_unit [1]
+# CHECK:             DW_AT_low_pc [DW_FORM_addr]       (0x0000000000400078)
+# CHECK-NEXT:        DW_AT_ranges [DW_FORM_sec_offset] (0x00000000
+# CHECK-NEXT:    [0x0000000000400078 - 0x0000000000400079)
+# CHECK-NEXT:    [0x000000000040007b - 0x000000000040007e)
+# CHECK-NEXT:    [0x000000000040007f - 0x0000000000400080))

diff --git a/test/DebugInfo/X86/dwarfdump-ranges-baseaddr.s b/test/DebugInfo/X86/dwarfdump-ranges-baseaddr.s
new file mode 100644 (file)
index 0000000..2377679
--- /dev/null
+++ b/test/DebugInfo/X86/dwarfdump-ranges-baseaddr.s
@@ -0,0 +1,82 @@
+# RUN: llvm-mc -triple x86_64-pc-linux -filetype=obj %s -o %t
+# RUN: llvm-dwarfdump %t | FileCheck %s
+
+# CHECK: .debug_info contents:
+# CHECK: 0x0000000b: DW_TAG_compile_unit [1]
+# CHECK:             DW_AT_low_pc [DW_FORM_addr]       (0x0000000000000000)
+# CHECK-NEXT:        DW_AT_ranges [DW_FORM_sec_offset] (0x00000000
+# CHECK-NEXT:    [0x0000000000000000 - 0x0000000000000001) ".text"
+# CHECK-NEXT:    [0x0000000000000003 - 0x0000000000000006) ".text"
+# CHECK-NEXT:    [0x0000000000000001 - 0x0000000000000002) ".text.foo1")
+
+.text
+.globl foo
+.type foo,@function
+foo: 
+.Lfunc_begin0:
+  nop
+.Ltmp0:
+  nop
+  nop
+.Ltmp1:
+  nop
+  nop
+  nop
+.Ltmp2:
+
+.section .text.foo1,"ax",@progbits
+.Ltmp3:
+ nop
+.Ltmp4: 
+ nop
+.Ltmp5:
+
+.section .debug_abbrev,"",@progbits
+.byte 1                       # Abbreviation Code
+.byte 17                      # DW_TAG_compile_unit
+.byte 0                       # DW_CHILDREN_no
+.byte 37                      # DW_AT_producer
+.byte 14                      # DW_FORM_strp
+.byte 19                      # DW_AT_language
+.byte 5                       # DW_FORM_data2
+.byte 3                       # DW_AT_name
+.byte 14                      # DW_FORM_strp
+.byte 16                      # DW_AT_stmt_list
+.byte 23                      # DW_FORM_sec_offset
+.byte 27                      # DW_AT_comp_dir
+.byte 14                      # DW_FORM_strp
+.byte 17                      # DW_AT_low_pc
+.byte 1                       # DW_FORM_addr
+.byte 85                      # DW_AT_ranges
+.byte 23                      # DW_FORM_sec_offset
+.byte 0                       # EOM(1)
+.byte 0                       # EOM(2)
+.byte 0                       # EOM(3)
+
+.section .debug_info,"",@progbits
+.Lcu_begin0:
+.long 38                      # Length of Unit
+.short 4                      # DWARF version number
+.long .debug_abbrev           # Offset Into Abbrev. Section
+.byte 8                       # Address Size (in bytes)
+.byte 1                       # Abbrev [1] 0xb:0x1f DW_TAG_compile_unit
+.long 0                       # DW_AT_producer
+.short 4                      # DW_AT_language
+.long 0                       # DW_AT_name
+.long 0                       # DW_AT_stmt_list
+.long 0                       # DW_AT_comp_dir
+.quad .Lfunc_begin0           # DW_AT_low_pc
+.long .Ldebug_ranges0         # DW_AT_ranges
+
+.section .debug_ranges,"",@progbits
+.Ldebug_ranges0:
+ .quad .Lfunc_begin0-.Lfunc_begin0
+ .quad .Ltmp0-.Lfunc_begin0
+ .quad .Ltmp1-.Lfunc_begin0
+ .quad .Ltmp2-.Lfunc_begin0
+ .quad 0xFFFFFFFFFFFFFFFF
+ .quad .text.foo1
+ .quad .Ltmp4-.text.foo1
+ .quad .Ltmp5-.text.foo1
+ .quad 0
+ .quad 0