Add RawRangeListsOffset

This allows us to distinguish offsets which may be relative to `DW_AT_GNU_ranges_base`.
saethlin · Jul 16, 2021 · 1a2439a · 1a2439a
1 parent 7c13056
commit 1a2439a
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Showing 7 changed files with 39 additions and 25 deletions.
diff --git a/benches/bench.rs b/benches/bench.rs
@@ -6,7 +6,7 @@ use gimli::{
     AttributeValue, DebugAbbrev, DebugAddr, DebugAddrBase, DebugAranges, DebugInfo, DebugLine,
     DebugLineOffset, DebugLoc, DebugLocLists, DebugPubNames, DebugPubTypes, DebugRanges,
     DebugRngLists, Encoding, EndianSlice, EntriesTreeNode, Expression, LittleEndian, LocationLists,
-    Operation, RangeLists, Reader, ReaderOffset,
+    Operation, RangeLists, RangeListsOffset, Reader, ReaderOffset,
 };
 use std::env;
 use std::fs::File;
@@ -384,7 +384,7 @@ fn bench_parsing_debug_ranges(b: &mut test::Bencher) {
             let mut attrs = entry.attrs();
             while let Some(attr) = attrs.next().expect("Should parse entry's attribute") {
                 if let gimli::AttributeValue::RangeListsRef(offset) = attr.value() {
-                    offsets.push((offset, unit.encoding(), low_pc));
+                    offsets.push((RangeListsOffset(offset.0), unit.encoding(), low_pc));
                 }
             }
         }

diff --git a/examples/dwarfdump.rs b/examples/dwarfdump.rs
@@ -1383,6 +1383,7 @@ fn dump_attr_value<R: Reader, W: Write>(
             writeln!(w, "<.debug_macro+0x{:08x}>", offset.0)?;
         }
         gimli::AttributeValue::RangeListsRef(offset) => {
+            let offset = dwarf.ranges_offset_from_raw(unit, offset);
             dump_range_list(w, offset, unit, dwarf)?;
         }
         gimli::AttributeValue::DebugRngListsBase(base) => {

diff --git a/src/common.rs b/src/common.rs
@@ -136,6 +136,14 @@ pub struct DebugMacinfoOffset<T = usize>(pub T);
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct DebugMacroOffset<T = usize>(pub T);
 
+/// An offset into either the `.debug_ranges` section or the `.debug_rnglists` section,
+/// depending on the version of the unit the offset was contained in.
+///
+/// If this is from a DWARF 4 DWO file, then it must additionally be offset by the
+/// value of `DW_AT_GNU_ranges_base`. You can use `Dwarf::ranges_offset_from_raw` to do this.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+pub struct RawRangeListsOffset<T = usize>(pub T);
+
 /// An offset into either the `.debug_ranges` section or the `.debug_rnglists` section,
 /// depending on the version of the unit the offset was contained in.
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]

diff --git a/src/read/dwarf.rs b/src/read/dwarf.rs
@@ -5,7 +5,7 @@ use crate::common::{
     DebugAddrBase, DebugAddrIndex, DebugInfoOffset, DebugLineStrOffset, DebugLocListsBase,
     DebugLocListsIndex, DebugRngListsBase, DebugRngListsIndex, DebugStrOffset, DebugStrOffsetsBase,
     DebugStrOffsetsIndex, DebugTypesOffset, DwarfFileType, Encoding, LocationListsOffset,
-    RangeListsOffset, SectionId, UnitSectionOffset,
+    RangeListsOffset, RawRangeListsOffset, SectionId, UnitSectionOffset,
 };
 use crate::constants;
 use crate::read::{
@@ -281,6 +281,21 @@ impl<R: Reader> Dwarf<R> {
         }
     }
 
+    /// Return the range list offset for the given raw offset.
+    ///
+    /// This handles adding `DW_AT_GNU_ranges_base` if required.
+    pub fn ranges_offset_from_raw(
+        &self,
+        unit: &Unit<R>,
+        offset: RawRangeListsOffset<R::Offset>,
+    ) -> RangeListsOffset<R::Offset> {
+        if self.file_type == DwarfFileType::Dwo && unit.header.version() < 5 {
+            RangeListsOffset(offset.0.wrapping_add(unit.rnglists_base.0))
+        } else {
+            RangeListsOffset(offset.0)
+        }
+    }
+
     /// Return the range list offset at the given index.
     pub fn ranges_offset(
         &self,
@@ -297,12 +312,6 @@ impl<R: Reader> Dwarf<R> {
         unit: &Unit<R>,
         offset: RangeListsOffset<R::Offset>,
     ) -> Result<RngListIter<R>> {
-        let offset = if self.file_type == DwarfFileType::Dwo && unit.header.version() < 5 {
-            RangeListsOffset(offset.0.wrapping_add(unit.rnglists_base.0))
-        } else {
-            offset
-        };
-
         self.ranges.ranges(
             offset,
             unit.encoding(),
@@ -318,11 +327,6 @@ impl<R: Reader> Dwarf<R> {
         unit: &Unit<R>,
         offset: RangeListsOffset<R::Offset>,
     ) -> Result<RawRngListIter<R>> {
-        let offset = if self.file_type == DwarfFileType::Dwo && unit.header.version() < 5 {
-            RangeListsOffset(offset.0.wrapping_add(unit.rnglists_base.0))
-        } else {
-            offset
-        };
         self.ranges.raw_ranges(offset, unit.encoding())
     }
 
@@ -341,7 +345,9 @@ impl<R: Reader> Dwarf<R> {
         attr: AttributeValue<R>,
     ) -> Result<Option<RangeListsOffset<R::Offset>>> {
         match attr {
-            AttributeValue::RangeListsRef(offset) => Ok(Some(offset)),
+            AttributeValue::RangeListsRef(offset) => {
+                Ok(Some(self.ranges_offset_from_raw(unit, offset)))
+            }
             AttributeValue::DebugRngListsIndex(index) => self.ranges_offset(unit, index).map(Some),
             _ => Ok(None),
         }

diff --git a/src/read/unit.rs b/src/read/unit.rs
@@ -9,7 +9,7 @@ use crate::common::{
     DebugLineStrOffset, DebugLocListsBase, DebugLocListsIndex, DebugMacinfoOffset,
     DebugMacroOffset, DebugRngListsBase, DebugRngListsIndex, DebugStrOffset, DebugStrOffsetsBase,
     DebugStrOffsetsIndex, DebugTypeSignature, DebugTypesOffset, DwoId, Encoding, Format,
-    LocationListsOffset, RangeListsOffset, SectionId, UnitSectionOffset,
+    LocationListsOffset, RawRangeListsOffset, SectionId, UnitSectionOffset,
 };
 use crate::constants;
 use crate::endianity::Endianity;
@@ -1044,7 +1044,7 @@ where
     DebugMacroRef(DebugMacroOffset<Offset>),
 
     /// An offset into the `.debug_ranges` section.
-    RangeListsRef(RangeListsOffset<Offset>),
+    RangeListsRef(RawRangeListsOffset<Offset>),
 
     /// An offset to a set of offsets in the `.debug_rnglists` section.
     DebugRngListsBase(DebugRngListsBase<Offset>),
@@ -1286,7 +1286,7 @@ impl<R: Reader> Attribute<R> {
             () => {
                 // DebugRngListsIndex is also an allowed form in DWARF version 5.
                 if let Some(offset) = self.offset_value() {
-                    return AttributeValue::RangeListsRef(RangeListsOffset(offset));
+                    return AttributeValue::RangeListsRef(RawRangeListsOffset(offset));
                 }
             };
         }

diff --git a/src/write/unit.rs b/src/write/unit.rs
@@ -1827,11 +1827,9 @@ pub(crate) mod convert {
                     let loc_id = context.locations.add(loc_list);
                     AttributeValue::LocationListRef(loc_id)
                 }
-                read::AttributeValue::RangeListsRef(val) => {
-                    let iter = context
-                        .dwarf
-                        .ranges
-                        .raw_ranges(val, context.unit.encoding())?;
+                read::AttributeValue::RangeListsRef(offset) => {
+                    let offset = context.dwarf.ranges_offset_from_raw(context.unit, offset);
+                    let iter = context.dwarf.raw_ranges(context.unit, offset)?;
                     let range_list = RangeList::from(iter, context)?;
                     let range_id = context.ranges.add(range_list);
                     AttributeValue::RangeListRef(range_id)

diff --git a/tests/parse_self.rs b/tests/parse_self.rs
@@ -3,7 +3,8 @@
 use gimli::{
     AttributeValue, DebugAbbrev, DebugAddr, DebugAddrBase, DebugAranges, DebugInfo, DebugLine,
     DebugLoc, DebugLocLists, DebugPubNames, DebugPubTypes, DebugRanges, DebugRngLists, DebugStr,
-    Encoding, EndianSlice, Expression, LittleEndian, LocationLists, Operation, RangeLists, Reader,
+    Encoding, EndianSlice, Expression, LittleEndian, LocationLists, Operation, RangeLists,
+    RangeListsOffset, Reader,
 };
 use std::collections::hash_map::HashMap;
 use std::env;
@@ -274,7 +275,7 @@ fn test_parse_self_debug_ranges() {
                 if let AttributeValue::RangeListsRef(offset) = attr.value() {
                     let mut ranges = rnglists
                         .ranges(
-                            offset,
+                            RangeListsOffset(offset.0),
                             unit.encoding(),
                             low_pc,
                             &debug_addr,