Add range & fix small bug

Author: diondokter

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+- Fix small crash when evaluating a variable location.
+  - Now it will accurately report that the memory doesn't exist instead of returning an error.
+- *Breaking*: Add range to memory region
+
 ## 0.10.1 (24-07-25)
 
 - Fix accidental use of std

core/src/memory_region.rs

@@ -9,6 +9,9 @@ pub const MEMORY_REGION_IDENTIFIER: u8 = 0x01;
 /// A collection of bytes that capture a memory region
 #[cfg(feature = "std")]
 pub trait MemoryRegion {
+    /// Get the address range of this region
+    fn range(&self) -> std::ops::Range<u64>;
+
     /// Returns the slice of memory that can be found at the given address_range.
     /// If the given address range is not fully within the captured region, then None is returned.
     fn read(
@@ -107,6 +110,10 @@ impl<const SIZE: usize> ArrayMemoryRegion<SIZE> {
 
 #[cfg(feature = "std")]
 impl<const SIZE: usize> MemoryRegion for ArrayMemoryRegion<SIZE> {
+    fn range(&self) -> std::ops::Range<u64> {
+        self.start_address..self.start_address + self.data.len() as u64
+    }
+
     fn read(
         &self,
         index: core::ops::Range<u64>,
@@ -238,6 +245,10 @@ impl VecMemoryRegion {
 
 #[cfg(feature = "std")]
 impl MemoryRegion for VecMemoryRegion {
+    fn range(&self) -> std::ops::Range<u64> {
+        self.start_address..self.start_address + self.data.len() as u64
+    }
+
     fn read(
         &self,
         index: core::ops::Range<u64>,
@@ -364,6 +375,11 @@ impl<'a> SliceMemoryRegion<'a> {
 
 #[cfg(feature = "std")]
 impl<'a> MemoryRegion for SliceMemoryRegion<'a> {
+    fn range(&self) -> std::ops::Range<u64> {
+        let range = self.data.as_ptr_range();
+        range.start as u64..range.end as u64
+    }
+
     fn read(
         &self,
         index: core::ops::Range<u64>,

trace/src/platform/mod.rs

@@ -234,18 +234,16 @@ fn add_current_frames<'a, P: Platform<'a>>(
 where
     <P::Word as funty::Numeric>::Bytes: bitvec::view::BitView<Store = u8>,
 {
+    let pc = device_memory.register(gimli::Arm::PC)?.as_u64();
+
     // Find the frames of the current register context
-    let mut context_frames = addr2line_context
-        .find_frames(device_memory.register(gimli::Arm::PC)?.as_u64())
-        .skip_all_loads()?;
+    let mut context_frames = addr2line_context.find_frames(pc).skip_all_loads()?;
 
     // Get the debug compilation unit of the current register context
     let unit_ref = addr2line_context
-        .find_dwarf_and_unit(device_memory.register(gimli::Arm::PC)?.as_u64())
+        .find_dwarf_and_unit(pc)
         .skip_all_loads()
-        .ok_or(TraceError::DwarfUnitNotFound {
-            pc: device_memory.register(gimli::Arm::PC)?.as_u64(),
-        })?;
+        .ok_or(TraceError::DwarfUnitNotFound { pc })?;
 
     // Get the abbreviations of the unit
     let abbreviations = unit_ref.dwarf.abbreviations(&unit_ref.header)?;

trace/src/variables/mod.rs

@@ -560,6 +560,7 @@ where
         Err(TraceError::LocationEvaluationStepNotImplemented(step)) => {
             Ok(VariableLocationResult::LocationEvaluationStepNotImplemented(step))
         }
+        Err(TraceError::MissingMemory(_)) => Ok(VariableLocationResult::NoLocationFound),
         Err(e) => Err(e),
         Ok(pieces) if pieces.is_empty() => Ok(VariableLocationResult::NoLocationFound),
         Ok(pieces) => Ok(VariableLocationResult::LocationsFound(pieces)),