pub enum Operation<R, Offset = <R as Reader>::Offset> where
R: Reader<Offset = Offset>,
Offset: ReaderOffset, {
Show 53 variants
Deref {
base_type: UnitOffset<Offset>,
size: u8,
space: bool,
},
Drop,
Pick {
index: u8,
},
Swap,
Rot,
Abs,
And,
Div,
Minus,
Mod,
Mul,
Neg,
Not,
Or,
Plus,
PlusConstant {
value: u64,
},
Shl,
Shr,
Shra,
Xor,
Bra {
target: i16,
},
Eq,
Ge,
Gt,
Le,
Lt,
Ne,
Skip {
target: i16,
},
UnsignedConstant {
value: u64,
},
SignedConstant {
value: i64,
},
Register {
register: Register,
},
RegisterOffset {
register: Register,
offset: i64,
base_type: UnitOffset<Offset>,
},
FrameOffset {
offset: i64,
},
Nop,
PushObjectAddress,
Call {
offset: DieReference<Offset>,
},
TLS,
CallFrameCFA,
Piece {
size_in_bits: u64,
bit_offset: Option<u64>,
},
ImplicitValue {
data: R,
},
StackValue,
ImplicitPointer {
value: DebugInfoOffset<Offset>,
byte_offset: i64,
},
EntryValue {
expression: R,
},
ParameterRef {
offset: UnitOffset<Offset>,
},
Address {
address: u64,
},
AddressIndex {
index: DebugAddrIndex<Offset>,
},
ConstantIndex {
index: DebugAddrIndex<Offset>,
},
TypedLiteral {
base_type: UnitOffset<Offset>,
value: R,
},
Convert {
base_type: UnitOffset<Offset>,
},
Reinterpret {
base_type: UnitOffset<Offset>,
},
WasmLocal {
index: u32,
},
WasmGlobal {
index: u32,
},
WasmStack {
index: u32,
},
}
Expand description
A single decoded DWARF expression operation.
DWARF expression evaluation is done in two parts: first the raw bytes of the next part of the expression are decoded; and then the decoded operation is evaluated. This approach lets other consumers inspect the DWARF expression without reimplementing the decoding operation.
Multiple DWARF opcodes may decode into a single Operation
. For
example, both DW_OP_deref
and DW_OP_xderef
are represented
using Operation::Deref
.
Variants
Deref
Fields
base_type: UnitOffset<Offset>
The DIE of the base type or 0 to indicate the generic type
size: u8
The size of the data to dereference.
space: bool
True if the dereference operation takes an address space argument from the stack; false otherwise.
Dereference the topmost value of the stack.
Drop
Drop an item from the stack.
Pick
Fields
index: u8
The index, from the top of the stack, of the item to copy.
Pick an item from the stack and push it on top of the stack.
This operation handles DW_OP_pick
, DW_OP_dup
, and
DW_OP_over
.
Swap
Swap the top two stack items.
Rot
Rotate the top three stack items.
Abs
Take the absolute value of the top of the stack.
And
Bitwise and
of the top two values on the stack.
Div
Divide the top two values on the stack.
Minus
Subtract the top two values on the stack.
Mod
Modulus of the top two values on the stack.
Mul
Multiply the top two values on the stack.
Neg
Negate the top of the stack.
Not
Bitwise not
of the top of the stack.
Or
Bitwise or
of the top two values on the stack.
Plus
Add the top two values on the stack.
PlusConstant
Fields
value: u64
The value to add.
Add a constant to the topmost value on the stack.
Shl
Logical left shift of the 2nd value on the stack by the number of bits given by the topmost value on the stack.
Shr
Right shift of the 2nd value on the stack by the number of bits given by the topmost value on the stack.
Shra
Arithmetic left shift of the 2nd value on the stack by the number of bits given by the topmost value on the stack.
Xor
Bitwise xor
of the top two values on the stack.
Bra
Fields
target: i16
The relative offset to the target bytecode.
Branch to the target location if the top of stack is nonzero.
Eq
Compare the top two stack values for equality.
Ge
Compare the top two stack values using >=
.
Gt
Compare the top two stack values using >
.
Le
Compare the top two stack values using <=
.
Lt
Compare the top two stack values using <
.
Ne
Compare the top two stack values using !=
.
Skip
Fields
target: i16
The relative offset to the target bytecode.
Unconditional branch to the target location.
UnsignedConstant
Fields
value: u64
The value to push.
Push an unsigned constant value on the stack. This handles multiple DWARF opcodes.
SignedConstant
Fields
value: i64
The value to push.
Push a signed constant value on the stack. This handles multiple DWARF opcodes.
Register
Fields
register: Register
The register number.
Indicate that this piece’s location is in the given register.
Completes the piece or expression.
RegisterOffset
Fields
register: Register
The register number.
offset: i64
The offset to add.
base_type: UnitOffset<Offset>
The DIE of the base type or 0 to indicate the generic type
Find the value of the given register, add the offset, and then push the resulting sum on the stack.
FrameOffset
Fields
offset: i64
The offset to add.
Compute the frame base (using DW_AT_frame_base
), add the
given offset, and then push the resulting sum on the stack.
Nop
No operation.
PushObjectAddress
Push the object address on the stack.
Call
Fields
offset: DieReference<Offset>
The DIE to use.
Evaluate a DWARF expression as a subroutine. The expression
comes from the DW_AT_location
attribute of the indicated
DIE.
TLS
Compute the address of a thread-local variable and push it on the stack.
CallFrameCFA
Compute the call frame CFA and push it on the stack.
Piece
Fields
size_in_bits: u64
The size of this piece in bits.
Terminate a piece.
ImplicitValue
The object has no location, but has a known constant value.
Represents DW_OP_implicit_value
.
Completes the piece or expression.
StackValue
The object has no location, but its value is at the top of the stack.
Represents DW_OP_stack_value
.
Completes the piece or expression.
ImplicitPointer
Fields
value: DebugInfoOffset<Offset>
The .debug_info
offset of the value that this is an implicit pointer into.
byte_offset: i64
The byte offset into the value that the implicit pointer points to.
The object is a pointer to a value which has no actual location, such as an implicit value or a stack value.
Represents DW_OP_implicit_pointer
.
Completes the piece or expression.
EntryValue
Evaluate an expression at the entry to the current subprogram, and push it on the stack.
Represents DW_OP_entry_value
.
ParameterRef
Fields
offset: UnitOffset<Offset>
The DIE to use.
This represents a parameter that was optimized out.
The offset points to the definition of the parameter, and is
matched to the DW_TAG_GNU_call_site_parameter
in the caller that also
points to the same definition of the parameter.
Represents DW_OP_GNU_parameter_ref
.
Address
Fields
address: u64
The offset to add.
Relocate the address if needed, and push it on the stack.
Represents DW_OP_addr
.
AddressIndex
Fields
index: DebugAddrIndex<Offset>
The index of the address in .debug_addr
.
Read the address at the given index in `.debug_addr, relocate the address if needed, and push it on the stack.
Represents DW_OP_addrx
.
ConstantIndex
Fields
index: DebugAddrIndex<Offset>
The index of the address in .debug_addr
.
Read the address at the given index in `.debug_addr, and push it on the stack. Do not relocate the address.
Represents DW_OP_constx
.
TypedLiteral
Interpret the value bytes as a constant of a given type, and push it on the stack.
Represents DW_OP_const_type
.
Convert
Fields
base_type: UnitOffset<Offset>
The DIE of the base type.
Pop the top stack entry, convert it to a different type, and push it on the stack.
Represents DW_OP_convert
.
Reinterpret
Fields
base_type: UnitOffset<Offset>
The DIE of the base type.
Pop the top stack entry, reinterpret the bits in its value as a different type, and push it on the stack.
Represents DW_OP_reinterpret
.
WasmLocal
Fields
index: u32
The index of the local.
The index of a local in the currently executing function.
Represents DW_OP_WASM_location 0x00
.
Completes the piece or expression.
WasmGlobal
Fields
index: u32
The index of the global.
The index of a global.
Represents DW_OP_WASM_location 0x01
or DW_OP_WASM_location 0x03
.
Completes the piece or expression.
WasmStack
Fields
index: u32
The index of the stack item. 0 is the bottom of the operand stack.
The index of an item on the operand stack.
Represents DW_OP_WASM_location 0x02
.
Completes the piece or expression.
Implementations
Parse a single DWARF expression operation.
This is useful when examining a DWARF expression for reasons other than direct evaluation.
bytes
points to a the operation to decode. It should point into
the same array as bytecode
, which should be the entire
expression.
Trait Implementations
impl<R: Copy, Offset: Copy> Copy for Operation<R, Offset> where
R: Reader<Offset = Offset>,
Offset: ReaderOffset,
impl<R: Eq, Offset: Eq> Eq for Operation<R, Offset> where
R: Reader<Offset = Offset>,
Offset: ReaderOffset,
impl<R, Offset> StructuralEq for Operation<R, Offset> where
R: Reader<Offset = Offset>,
Offset: ReaderOffset,
impl<R, Offset> StructuralPartialEq for Operation<R, Offset> where
R: Reader<Offset = Offset>,
Offset: ReaderOffset,
Auto Trait Implementations
impl<R, Offset> RefUnwindSafe for Operation<R, Offset> where
Offset: RefUnwindSafe,
R: RefUnwindSafe,
impl<R, Offset> UnwindSafe for Operation<R, Offset> where
Offset: UnwindSafe,
R: UnwindSafe,
Blanket Implementations
Mutably borrows from an owned value. Read more