Struct FunctionCx

pub struct FunctionCx<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> {

    instance: Instance<'tcx>,
    mir: &'tcx Body<'tcx>,
    debug_context: Option<FunctionDebugContext<'tcx, Bx::DIScope, Bx::DILocation>>,
    llfn: Bx::Function,
    cx: &'a Bx::CodegenCx,
    fn_abi: &'tcx FnAbi<'tcx, Ty<'tcx>>,
    personality_slot: Option<PlaceRef<'tcx, Bx::Value>>,
    cached_llbbs: IndexVec<BasicBlock, CachedLlbb<Bx::BasicBlock>>,
    cleanup_kinds: Option<IndexVec<BasicBlock, CleanupKind>>,
    funclets: IndexVec<BasicBlock, Option<Bx::Funclet>>,
    landing_pads: IndexVec<BasicBlock, Option<Bx::BasicBlock>>,
    unreachable_block: Option<Bx::BasicBlock>,
    terminate_block: Option<(Bx::BasicBlock, UnwindTerminateReason)>,
    cold_blocks: IndexVec<BasicBlock, bool>,
    locals: Locals<'tcx, Bx::Value>,
    per_local_var_debug_info: Option<IndexVec<Local, Vec<PerLocalVarDebugInfo<'tcx, Bx::DIVariable>>>>,
    caller_location: Option<OperandRef<'tcx, Bx::Value>>,
}

Master context for codegenning from MIR.

Fields

instance: Instance<'tcx>

mir: &'tcx Body<'tcx>

debug_context: Option<FunctionDebugContext<'tcx, Bx::DIScope, Bx::DILocation>>

llfn: Bx::Function

cx: &'a Bx::CodegenCx

fn_abi: &'tcx FnAbi<'tcx, Ty<'tcx>>

personality_slot: Option<PlaceRef<'tcx, Bx::Value>>

When unwinding is initiated, we have to store this personality value somewhere so that we can load it and re-use it in the resume instruction. The personality is (afaik) some kind of value used for C++ unwinding, which must filter by type: we don’t really care about it very much. Anyway, this value contains an alloca into which the personality is stored and then later loaded when generating the DIVERGE_BLOCK.

cached_llbbs: IndexVec<BasicBlock, CachedLlbb<Bx::BasicBlock>>

A backend BasicBlock for each MIR BasicBlock, created lazily as-needed (e.g. RPO reaching it or another block branching to it).

cleanup_kinds: Option<IndexVec<BasicBlock, CleanupKind>>

The funclet status of each basic block

funclets: IndexVec<BasicBlock, Option<Bx::Funclet>>

When targeting MSVC, this stores the cleanup info for each funclet BB. This is initialized at the same time as the landing_pads entry for the funclets’ head block, i.e. when needed by an unwind / cleanup_ret edge.

landing_pads: IndexVec<BasicBlock, Option<Bx::BasicBlock>>

This stores the cached landing/cleanup pad block for a given BB.

unreachable_block: Option<Bx::BasicBlock>

Cached unreachable block

terminate_block: Option<(Bx::BasicBlock, UnwindTerminateReason)>

Cached terminate upon unwinding block and its reason

cold_blocks: IndexVec<BasicBlock, bool>

A bool flag for each basic block indicating whether it is a cold block. A cold block is a block that is unlikely to be executed at runtime.

locals: Locals<'tcx, Bx::Value>

The location where each MIR arg/var/tmp/ret is stored. This is usually an PlaceRef representing an alloca, but not always: sometimes we can skip the alloca and just store the value directly using an OperandRef, which makes for tighter LLVM IR. The conditions for using an OperandRef are as follows:

• the type of the local must be judged “immediate” by is_llvm_immediate
• the operand must never be referenced indirectly
  • we should not take its address using the & operator
  • nor should it appear in a place path like tmp.a
• the operand must be defined by an rvalue that can generate immediate values

Avoiding allocs can also be important for certain intrinsics, notably expect.

per_local_var_debug_info: Option<IndexVec<Local, Vec<PerLocalVarDebugInfo<'tcx, Bx::DIVariable>>>>

All VarDebugInfo from the MIR body, partitioned by Local. This is None if no variable debuginfo/names are needed.

caller_location: Option<OperandRef<'tcx, Bx::Value>>

Caller location propagated if this function has #[track_caller].

Implementations

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

Codegen implementations for some terminator variants.

fn codegen_resume_terminator( &mut self, helper: TerminatorCodegenHelper<'tcx>, bx: &mut Bx, )

Generates code for a Resume terminator.

fn codegen_switchint_terminator( &mut self, helper: TerminatorCodegenHelper<'tcx>, bx: &mut Bx, discr: &Operand<'tcx>, targets: &SwitchTargets, )

fn codegen_return_terminator(&mut self, bx: &mut Bx)

fn codegen_drop_terminator( &mut self, helper: TerminatorCodegenHelper<'tcx>, bx: &mut Bx, source_info: &SourceInfo, location: Place<'tcx>, target: BasicBlock, unwind: UnwindAction, mergeable_succ: bool, ) -> MergingSucc

fn codegen_assert_terminator( &mut self, helper: TerminatorCodegenHelper<'tcx>, bx: &mut Bx, terminator: &Terminator<'tcx>, cond: &Operand<'tcx>, expected: bool, msg: &AssertMessage<'tcx>, target: BasicBlock, unwind: UnwindAction, mergeable_succ: bool, ) -> MergingSucc

fn codegen_terminate_terminator( &mut self, helper: TerminatorCodegenHelper<'tcx>, bx: &mut Bx, terminator: &Terminator<'tcx>, reason: UnwindTerminateReason, )

fn codegen_panic_intrinsic( &mut self, helper: &TerminatorCodegenHelper<'tcx>, bx: &mut Bx, intrinsic: IntrinsicDef, instance: Instance<'tcx>, source_info: SourceInfo, target: Option<BasicBlock>, unwind: UnwindAction, mergeable_succ: bool, ) -> Option<MergingSucc>

Returns Some if this is indeed a panic intrinsic and codegen is done.

fn codegen_call_terminator( &mut self, helper: TerminatorCodegenHelper<'tcx>, bx: &mut Bx, terminator: &Terminator<'tcx>, func: &Operand<'tcx>, args: &[Spanned<Operand<'tcx>>], destination: Place<'tcx>, target: Option<BasicBlock>, unwind: UnwindAction, fn_span: Span, mergeable_succ: bool, ) -> MergingSucc

fn codegen_asm_terminator( &mut self, helper: TerminatorCodegenHelper<'tcx>, bx: &mut Bx, asm_macro: InlineAsmMacro, terminator: &Terminator<'tcx>, template: &[InlineAsmTemplatePiece], operands: &[InlineAsmOperand<'tcx>], options: InlineAsmOptions, line_spans: &[Span], targets: &[BasicBlock], unwind: UnwindAction, instance: Instance<'_>, mergeable_succ: bool, ) -> MergingSucc

pub(crate) fn codegen_block(&mut self, bb: BasicBlock)

pub(crate) fn codegen_block_as_unreachable(&mut self, bb: BasicBlock)

fn codegen_terminator( &mut self, bx: &mut Bx, bb: BasicBlock, terminator: &'tcx Terminator<'tcx>, ) -> MergingSucc

fn codegen_argument( &mut self, bx: &mut Bx, op: OperandRef<'tcx, Bx::Value>, llargs: &mut Vec<Bx::Value>, arg: &ArgAbi<'tcx, Ty<'tcx>>, lifetime_ends_after_call: &mut Vec<(Bx::Value, Size)>, )

fn codegen_arguments_untupled( &mut self, bx: &mut Bx, operand: &Operand<'tcx>, llargs: &mut Vec<Bx::Value>, args: &[ArgAbi<'tcx, Ty<'tcx>>], lifetime_ends_after_call: &mut Vec<(Bx::Value, Size)>, ) -> usize

pub(super) fn get_caller_location( &mut self, bx: &mut Bx, source_info: SourceInfo, ) -> OperandRef<'tcx, Bx::Value>

fn get_personality_slot(&mut self, bx: &mut Bx) -> PlaceRef<'tcx, Bx::Value>

fn landing_pad_for(&mut self, bb: BasicBlock) -> Bx::BasicBlock

Returns the landing/cleanup pad wrapper around the given basic block.

fn landing_pad_for_uncached(&mut self, bb: BasicBlock) -> Bx::BasicBlock

fn unreachable_block(&mut self) -> Bx::BasicBlock

fn terminate_block(&mut self, reason: UnwindTerminateReason) -> Bx::BasicBlock

pub fn llbb(&mut self, bb: BasicBlock) -> Bx::BasicBlock

Get the backend BasicBlock for a MIR BasicBlock, either already cached in self.cached_llbbs, or created on demand (and cached).

pub(crate) fn try_llbb(&mut self, bb: BasicBlock) -> Option<Bx::BasicBlock>

Like llbb, but may fail if the basic block should be skipped.

fn make_return_dest( &mut self, bx: &mut Bx, dest: Place<'tcx>, fn_ret: &ArgAbi<'tcx, Ty<'tcx>>, llargs: &mut Vec<Bx::Value>, ) -> ReturnDest<'tcx, Bx::Value>

fn store_return( &mut self, bx: &mut Bx, dest: ReturnDest<'tcx, Bx::Value>, ret_abi: &ArgAbi<'tcx, Ty<'tcx>>, llval: Bx::Value, )

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub(crate) fn eval_mir_constant_to_operand( &self, bx: &mut Bx, constant: &ConstOperand<'tcx>, ) -> OperandRef<'tcx, Bx::Value>

pub fn eval_mir_constant( &self, constant: &ConstOperand<'tcx>, ) -> ConstValue<'tcx>

fn eval_unevaluated_mir_constant_to_valtree( &self, constant: &ConstOperand<'tcx>, ) -> Result<Result<ValTree<'tcx>, Ty<'tcx>>, ErrorHandled>

This is a convenience helper for immediate_const_vector. It has the precondition that the given constant is an Const::Unevaluated and must be convertible to a ValTree. If you want a more general version of this, talk to wg-const-eval on zulip.

Note that this function is cursed, since usually MIR consts should not be evaluated to valtrees!

pub fn immediate_const_vector( &mut self, bx: &Bx, constant: &ConstOperand<'tcx>, ) -> (Bx::Value, Ty<'tcx>)

process constant containing SIMD shuffle indices & constant vectors

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub(crate) fn codegen_coverage( &self, bx: &mut Bx, kind: &CoverageKind, scope: SourceScope, )

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub fn set_debug_loc(&self, bx: &mut Bx, source_info: SourceInfo)

fn dbg_loc(&self, source_info: SourceInfo) -> Option<Bx::DILocation>

fn adjusted_span_and_dbg_scope( &self, source_info: SourceInfo, ) -> Option<(Bx::DIScope, Option<Bx::DILocation>, Span)>

fn spill_operand_to_stack( operand: OperandRef<'tcx, Bx::Value>, name: Option<String>, bx: &mut Bx, ) -> PlaceRef<'tcx, Bx::Value>

pub(crate) fn debug_introduce_local(&self, bx: &mut Bx, local: Local)

Apply debuginfo and/or name, after creating the alloca for a local, or initializing the local with an operand (whichever applies).

fn debug_introduce_local_as_var( &self, bx: &mut Bx, local: Local, base: PlaceRef<'tcx, Bx::Value>, var: PerLocalVarDebugInfo<'tcx, Bx::DIVariable>, )

pub(crate) fn debug_introduce_locals( &self, bx: &mut Bx, consts: Vec<ConstDebugInfo<'a, 'tcx, Bx>>, )

pub(crate) fn compute_per_local_var_debug_info( &self, bx: &mut Bx, ) -> Option<(IndexVec<Local, Vec<PerLocalVarDebugInfo<'tcx, Bx::DIVariable>>>, Vec<ConstDebugInfo<'a, 'tcx, Bx>>)>

Partition all VarDebugInfo in self.mir, by their base Local.

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub fn codegen_intrinsic_call( &mut self, bx: &mut Bx, instance: Instance<'tcx>, args: &[OperandRef<'tcx, Bx::Value>], result: PlaceRef<'tcx, Bx::Value>, source_info: SourceInfo, ) -> Result<(), Instance<'tcx>>

In the Err case, returns the instance that should be called instead.

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub(super) fn initialize_locals( &mut self, values: Vec<LocalRef<'tcx, Bx::Value>>, )

pub(super) fn overwrite_local( &mut self, local: Local, value: LocalRef<'tcx, Bx::Value>, )

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

fn maybe_codegen_consume_direct( &mut self, bx: &mut Bx, place_ref: PlaceRef<'tcx>, ) -> Option<OperandRef<'tcx, Bx::Value>>

pub fn codegen_consume( &mut self, bx: &mut Bx, place_ref: PlaceRef<'tcx>, ) -> OperandRef<'tcx, Bx::Value>

pub fn codegen_operand( &mut self, bx: &mut Bx, operand: &Operand<'tcx>, ) -> OperandRef<'tcx, Bx::Value>

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub fn codegen_place( &mut self, bx: &mut Bx, place_ref: PlaceRef<'tcx>, ) -> PlaceRef<'tcx, Bx::Value>

pub fn monomorphized_place_ty(&self, place_ref: PlaceRef<'tcx>) -> Ty<'tcx>

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub(crate) fn codegen_rvalue( &mut self, bx: &mut Bx, dest: PlaceRef<'tcx, Bx::Value>, rvalue: &Rvalue<'tcx>, )

fn codegen_transmute( &mut self, bx: &mut Bx, src: OperandRef<'tcx, Bx::Value>, dst: PlaceRef<'tcx, Bx::Value>, )

Transmutes the src value to the destination type by writing it to dst.

See also Self::codegen_transmute_operand for cases that can be done without needing a pre-allocated place for the destination.

pub(crate) fn codegen_transmute_operand( &mut self, bx: &mut Bx, operand: OperandRef<'tcx, Bx::Value>, cast: TyAndLayout<'tcx>, ) -> OperandValue<Bx::Value>

Transmutes an OperandValue to another OperandValue.

This is supported only for cases where Self::rvalue_creates_operand returns true, and will ICE otherwise. (In particular, anything that would need to alloca in order to return a PlaceValue will ICE, expecting those to go via Self::codegen_transmute instead where the destination place is already allocated.)

fn cast_immediate( &self, bx: &mut Bx, imm: Bx::Value, from_scalar: Scalar, from_backend_ty: Bx::Type, to_scalar: Scalar, to_backend_ty: Bx::Type, ) -> Option<Bx::Value>

Cast one of the immediates from an OperandValue::Immediate or an OperandValue::Pair to an immediate of the target type.

Returns None if the cast is not possible.

pub(crate) fn codegen_rvalue_unsized( &mut self, bx: &mut Bx, indirect_dest: PlaceRef<'tcx, Bx::Value>, rvalue: &Rvalue<'tcx>, )

pub(crate) fn codegen_rvalue_operand( &mut self, bx: &mut Bx, rvalue: &Rvalue<'tcx>, ) -> OperandRef<'tcx, Bx::Value>

fn evaluate_array_len(&mut self, bx: &mut Bx, place: Place<'tcx>) -> Bx::Value

fn codegen_place_to_pointer( &mut self, bx: &mut Bx, place: Place<'tcx>, mk_ptr_ty: impl FnOnce(TyCtxt<'tcx>, Ty<'tcx>) -> Ty<'tcx>, ) -> OperandRef<'tcx, Bx::Value>

Codegen an Rvalue::RawPtr or Rvalue::Ref

fn codegen_scalar_binop( &mut self, bx: &mut Bx, op: BinOp, lhs: Bx::Value, rhs: Bx::Value, lhs_ty: Ty<'tcx>, rhs_ty: Ty<'tcx>, ) -> Bx::Value

fn codegen_wide_ptr_binop( &mut self, bx: &mut Bx, op: BinOp, lhs_addr: Bx::Value, lhs_extra: Bx::Value, rhs_addr: Bx::Value, rhs_extra: Bx::Value, _input_ty: Ty<'tcx>, ) -> Bx::Value

fn codegen_scalar_checked_binop( &mut self, bx: &mut Bx, op: BinOp, lhs: Bx::Value, rhs: Bx::Value, input_ty: Ty<'tcx>, ) -> OperandValue<Bx::Value>

pub(crate) fn rvalue_creates_operand( &self, rvalue: &Rvalue<'tcx>, span: Span, ) -> bool

Returns true if the rvalue can be computed into an OperandRef, rather than needing a full PlaceRef for the assignment destination.

This is used by the super::analyze code to decide which MIR locals can stay as SSA values (as opposed to generating alloca slots for them). As such, some paths here return true even where the specific rvalue will not actually take the operand path because the result type is such that it always gets an alloca, but where it’s not worth re-checking the layout in this code when the right thing will happen anyway.

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub(crate) fn codegen_statement( &mut self, bx: &mut Bx, statement: &Statement<'tcx>, )

impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx>

pub fn monomorphize<T>(&self, value: T) -> T

where T: Copy + TypeFoldable<TyCtxt<'tcx>>,

Layout

Note: Unable to compute type layout, possibly due to this type having generic parameters. Layout can only be computed for concrete, fully-instantiated types.