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use rustc::ty::{self, Ty, TypeFoldable, UpvarSubsts, Instance};
use rustc::ty::layout::{TyLayout, HasTyCtxt, FnTypeExt};
use rustc::mir::{self, Body};
use rustc::session::config::DebugInfo;
use rustc_target::abi::call::{FnType, PassMode, IgnoreMode};
use rustc_target::abi::{Variants, VariantIdx};
use crate::base;
use crate::debuginfo::{self, VariableAccess, VariableKind, FunctionDebugContext};
use crate::traits::*;
use syntax_pos::{DUMMY_SP, NO_EXPANSION, BytePos, Span};
use syntax::symbol::kw;
use std::iter;
use rustc_data_structures::bit_set::BitSet;
use rustc_data_structures::indexed_vec::IndexVec;
use self::analyze::CleanupKind;
use self::place::PlaceRef;
use rustc::mir::traversal;
use self::operand::{OperandRef, OperandValue};
/// Master context for codegenning from MIR.
pub struct FunctionCx<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> {
instance: Instance<'tcx>,
mir: &'a mir::Body<'tcx>,
debug_context: FunctionDebugContext<Bx::DIScope>,
llfn: Bx::Value,
cx: &'a Bx::CodegenCx,
fn_ty: FnType<'tcx, Ty<'tcx>>,
/// 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.
personality_slot: Option<PlaceRef<'tcx, Bx::Value>>,
/// A `Block` for each MIR `BasicBlock`
blocks: IndexVec<mir::BasicBlock, Bx::BasicBlock>,
/// The funclet status of each basic block
cleanup_kinds: IndexVec<mir::BasicBlock, analyze::CleanupKind>,
/// When targeting MSVC, this stores the cleanup info for each funclet
/// BB. This is initialized as we compute the funclets' head block in RPO.
funclets: IndexVec<mir::BasicBlock, Option<Bx::Funclet>>,
/// This stores the landing-pad block for a given BB, computed lazily on GNU
/// and eagerly on MSVC.
landing_pads: IndexVec<mir::BasicBlock, Option<Bx::BasicBlock>>,
/// Cached unreachable block
unreachable_block: Option<Bx::BasicBlock>,
/// 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`.
locals: IndexVec<mir::Local, LocalRef<'tcx, Bx::Value>>,
/// Debug information for MIR scopes.
scopes: IndexVec<mir::SourceScope, debuginfo::MirDebugScope<Bx::DIScope>>,
/// If this function is a C-variadic function, this contains the `PlaceRef` of the
/// "spoofed" `VaListImpl`.
va_list_ref: Option<PlaceRef<'tcx, Bx::Value>>,
}
impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
pub fn monomorphize<T>(&self, value: &T) -> T
where T: TypeFoldable<'tcx>
{
self.cx.tcx().subst_and_normalize_erasing_regions(
self.instance.substs,
ty::ParamEnv::reveal_all(),
value,
)
}
pub fn set_debug_loc(
&mut self,
bx: &mut Bx,
source_info: mir::SourceInfo
) {
let (scope, span) = self.debug_loc(source_info);
bx.set_source_location(&mut self.debug_context, scope, span);
}
pub fn debug_loc(&self, source_info: mir::SourceInfo) -> (Option<Bx::DIScope>, Span) {
// Bail out if debug info emission is not enabled.
match self.debug_context {
FunctionDebugContext::DebugInfoDisabled |
FunctionDebugContext::FunctionWithoutDebugInfo => {
return (self.scopes[source_info.scope].scope_metadata, source_info.span);
}
FunctionDebugContext::RegularContext(_) =>{}
}
// In order to have a good line stepping behavior in debugger, we overwrite debug
// locations of macro expansions with that of the outermost expansion site
// (unless the crate is being compiled with `-Z debug-macros`).
if source_info.span.ctxt() == NO_EXPANSION ||
self.cx.sess().opts.debugging_opts.debug_macros {
let scope = self.scope_metadata_for_loc(source_info.scope, source_info.span.lo());
(scope, source_info.span)
} else {
// Walk up the macro expansion chain until we reach a non-expanded span.
// We also stop at the function body level because no line stepping can occur
// at the level above that.
let span = syntax_pos::hygiene::walk_chain(source_info.span, self.mir.span.ctxt());
let scope = self.scope_metadata_for_loc(source_info.scope, span.lo());
// Use span of the outermost expansion site, while keeping the original lexical scope.
(scope, span)
}
}
// DILocations inherit source file name from the parent DIScope. Due to macro expansions
// it may so happen that the current span belongs to a different file than the DIScope
// corresponding to span's containing source scope. If so, we need to create a DIScope
// "extension" into that file.
fn scope_metadata_for_loc(&self, scope_id: mir::SourceScope, pos: BytePos)
-> Option<Bx::DIScope> {
let scope_metadata = self.scopes[scope_id].scope_metadata;
if pos < self.scopes[scope_id].file_start_pos ||
pos >= self.scopes[scope_id].file_end_pos {
let sm = self.cx.sess().source_map();
let defining_crate = self.debug_context.get_ref(DUMMY_SP).defining_crate;
Some(self.cx.extend_scope_to_file(
scope_metadata.unwrap(),
&sm.lookup_char_pos(pos).file,
defining_crate
))
} else {
scope_metadata
}
}
}
enum LocalRef<'tcx, V> {
Place(PlaceRef<'tcx, V>),
/// `UnsizedPlace(p)`: `p` itself is a thin pointer (indirect place).
/// `*p` is the fat pointer that references the actual unsized place.
/// Every time it is initialized, we have to reallocate the place
/// and update the fat pointer. That's the reason why it is indirect.
UnsizedPlace(PlaceRef<'tcx, V>),
Operand(Option<OperandRef<'tcx, V>>),
}
impl<'a, 'tcx, V: CodegenObject> LocalRef<'tcx, V> {
fn new_operand<Bx: BuilderMethods<'a, 'tcx, Value = V>>(
bx: &mut Bx,
layout: TyLayout<'tcx>,
) -> LocalRef<'tcx, V> {
if layout.is_zst() {
// Zero-size temporaries aren't always initialized, which
// doesn't matter because they don't contain data, but
// we need something in the operand.
LocalRef::Operand(Some(OperandRef::new_zst(bx, layout)))
} else {
LocalRef::Operand(None)
}
}
}
///////////////////////////////////////////////////////////////////////////
pub fn codegen_mir<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
cx: &'a Bx::CodegenCx,
llfn: Bx::Value,
mir: &'a Body<'tcx>,
instance: Instance<'tcx>,
sig: ty::FnSig<'tcx>,
) {
assert!(!instance.substs.needs_infer());
let fn_ty = FnType::new(cx, sig, &[]);
debug!("fn_ty: {:?}", fn_ty);
let mut debug_context =
cx.create_function_debug_context(instance, sig, llfn, mir);
let mut bx = Bx::new_block(cx, llfn, "start");
if mir.basic_blocks().iter().any(|bb| bb.is_cleanup) {
bx.set_personality_fn(cx.eh_personality());
}
let cleanup_kinds = analyze::cleanup_kinds(&mir);
// Allocate a `Block` for every basic block, except
// the start block, if nothing loops back to it.
let reentrant_start_block = !mir.predecessors_for(mir::START_BLOCK).is_empty();
let block_bxs: IndexVec<mir::BasicBlock, Bx::BasicBlock> =
mir.basic_blocks().indices().map(|bb| {
if bb == mir::START_BLOCK && !reentrant_start_block {
bx.llbb()
} else {
bx.build_sibling_block(&format!("{:?}", bb)).llbb()
}
}).collect();
// Compute debuginfo scopes from MIR scopes.
let scopes = cx.create_mir_scopes(mir, &mut debug_context);
let (landing_pads, funclets) = create_funclets(mir, &mut bx, &cleanup_kinds, &block_bxs);
let mut fx = FunctionCx {
instance,
mir,
llfn,
fn_ty,
cx,
personality_slot: None,
blocks: block_bxs,
unreachable_block: None,
cleanup_kinds,
landing_pads,
funclets,
scopes,
locals: IndexVec::new(),
debug_context,
va_list_ref: None,
};
let memory_locals = analyze::non_ssa_locals(&fx);
// Allocate variable and temp allocas
fx.locals = {
// FIXME(dlrobertson): This is ugly. Find a better way of getting the `PlaceRef` or
// `LocalRef` from `arg_local_refs`
let mut va_list_ref = None;
let args = arg_local_refs(&mut bx, &fx, &memory_locals, &mut va_list_ref);
fx.va_list_ref = va_list_ref;
let mut allocate_local = |local| {
let decl = &mir.local_decls[local];
let layout = bx.layout_of(fx.monomorphize(&decl.ty));
assert!(!layout.ty.has_erasable_regions());
if let Some(name) = decl.name {
// User variable
let debug_scope = fx.scopes[decl.visibility_scope];
let dbg = debug_scope.is_valid() &&
bx.sess().opts.debuginfo == DebugInfo::Full;
if !memory_locals.contains(local) && !dbg {
debug!("alloc: {:?} ({}) -> operand", local, name);
return LocalRef::new_operand(&mut bx, layout);
}
debug!("alloc: {:?} ({}) -> place", local, name);
if layout.is_unsized() {
let indirect_place =
PlaceRef::alloca_unsized_indirect(&mut bx, layout, &name.as_str());
// FIXME: add an appropriate debuginfo
LocalRef::UnsizedPlace(indirect_place)
} else {
let place = PlaceRef::alloca(&mut bx, layout, &name.as_str());
if dbg {
let (scope, span) = fx.debug_loc(mir::SourceInfo {
span: decl.source_info.span,
scope: decl.visibility_scope,
});
bx.declare_local(&fx.debug_context, name, layout.ty, scope.unwrap(),
VariableAccess::DirectVariable { alloca: place.llval },
VariableKind::LocalVariable, span);
}
LocalRef::Place(place)
}
} else {
// Temporary or return place
if local == mir::RETURN_PLACE && fx.fn_ty.ret.is_indirect() {
debug!("alloc: {:?} (return place) -> place", local);
let llretptr = bx.get_param(0);
LocalRef::Place(PlaceRef::new_sized(llretptr, layout, layout.align.abi))
} else if memory_locals.contains(local) {
debug!("alloc: {:?} -> place", local);
if layout.is_unsized() {
let indirect_place = PlaceRef::alloca_unsized_indirect(
&mut bx,
layout,
&format!("{:?}", local),
);
LocalRef::UnsizedPlace(indirect_place)
} else {
LocalRef::Place(PlaceRef::alloca(&mut bx, layout, &format!("{:?}", local)))
}
} else {
// If this is an immediate local, we do not create an
// alloca in advance. Instead we wait until we see the
// definition and update the operand there.
debug!("alloc: {:?} -> operand", local);
LocalRef::new_operand(&mut bx, layout)
}
}
};
let retptr = allocate_local(mir::RETURN_PLACE);
iter::once(retptr)
.chain(args.into_iter())
.chain(mir.vars_and_temps_iter().map(allocate_local))
.collect()
};
// Branch to the START block, if it's not the entry block.
if reentrant_start_block {
bx.br(fx.blocks[mir::START_BLOCK]);
}
// Up until here, IR instructions for this function have explicitly not been annotated with
// source code location, so we don't step into call setup code. From here on, source location
// emitting should be enabled.
debuginfo::start_emitting_source_locations(&mut fx.debug_context);
let rpo = traversal::reverse_postorder(&mir);
let mut visited = BitSet::new_empty(mir.basic_blocks().len());
// Codegen the body of each block using reverse postorder
for (bb, _) in rpo {
visited.insert(bb.index());
fx.codegen_block(bb);
}
// Remove blocks that haven't been visited, or have no
// predecessors.
for bb in mir.basic_blocks().indices() {
// Unreachable block
if !visited.contains(bb.index()) {
debug!("codegen_mir: block {:?} was not visited", bb);
unsafe {
bx.delete_basic_block(fx.blocks[bb]);
}
}
}
}
fn create_funclets<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
mir: &'a Body<'tcx>,
bx: &mut Bx,
cleanup_kinds: &IndexVec<mir::BasicBlock, CleanupKind>,
block_bxs: &IndexVec<mir::BasicBlock, Bx::BasicBlock>,
) -> (
IndexVec<mir::BasicBlock, Option<Bx::BasicBlock>>,
IndexVec<mir::BasicBlock, Option<Bx::Funclet>>,
) {
block_bxs.iter_enumerated().zip(cleanup_kinds).map(|((bb, &llbb), cleanup_kind)| {
match *cleanup_kind {
CleanupKind::Funclet if base::wants_msvc_seh(bx.sess()) => {}
_ => return (None, None)
}
let funclet;
let ret_llbb;
match mir[bb].terminator.as_ref().map(|t| &t.kind) {
// This is a basic block that we're aborting the program for,
// notably in an `extern` function. These basic blocks are inserted
// so that we assert that `extern` functions do indeed not panic,
// and if they do we abort the process.
//
// On MSVC these are tricky though (where we're doing funclets). If
// we were to do a cleanuppad (like below) the normal functions like
// `longjmp` would trigger the abort logic, terminating the
// program. Instead we insert the equivalent of `catch(...)` for C++
// which magically doesn't trigger when `longjmp` files over this
// frame.
//
// Lots more discussion can be found on #48251 but this codegen is
// modeled after clang's for:
//
// try {
// foo();
// } catch (...) {
// bar();
// }
Some(&mir::TerminatorKind::Abort) => {
let mut cs_bx = bx.build_sibling_block(&format!("cs_funclet{:?}", bb));
let mut cp_bx = bx.build_sibling_block(&format!("cp_funclet{:?}", bb));
ret_llbb = cs_bx.llbb();
let cs = cs_bx.catch_switch(None, None, 1);
cs_bx.add_handler(cs, cp_bx.llbb());
// The "null" here is actually a RTTI type descriptor for the
// C++ personality function, but `catch (...)` has no type so
// it's null. The 64 here is actually a bitfield which
// represents that this is a catch-all block.
let null = bx.const_null(bx.type_i8p());
let sixty_four = bx.const_i32(64);
funclet = cp_bx.catch_pad(cs, &[null, sixty_four, null]);
cp_bx.br(llbb);
}
_ => {
let mut cleanup_bx = bx.build_sibling_block(&format!("funclet_{:?}", bb));
ret_llbb = cleanup_bx.llbb();
funclet = cleanup_bx.cleanup_pad(None, &[]);
cleanup_bx.br(llbb);
}
};
(Some(ret_llbb), Some(funclet))
}).unzip()
}
/// Produces, for each argument, a `Value` pointing at the
/// argument's value. As arguments are places, these are always
/// indirect.
fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
bx: &mut Bx,
fx: &FunctionCx<'a, 'tcx, Bx>,
memory_locals: &BitSet<mir::Local>,
va_list_ref: &mut Option<PlaceRef<'tcx, Bx::Value>>,
) -> Vec<LocalRef<'tcx, Bx::Value>> {
let mir = fx.mir;
let tcx = fx.cx.tcx();
let mut idx = 0;
let mut llarg_idx = fx.fn_ty.ret.is_indirect() as usize;
// Get the argument scope, if it exists and if we need it.
let arg_scope = fx.scopes[mir::OUTERMOST_SOURCE_SCOPE];
let arg_scope = if bx.sess().opts.debuginfo == DebugInfo::Full {
arg_scope.scope_metadata
} else {
None
};
// Store the index of the last argument. This is used to
// call va_start on the va_list instead of attempting
// to store_fn_arg.
let last_arg_idx = if fx.fn_ty.args.is_empty() {
None
} else {
Some(fx.fn_ty.args.len() - 1)
};
mir.args_iter().enumerate().map(|(arg_index, local)| {
let arg_decl = &mir.local_decls[local];
let name = if let Some(name) = arg_decl.name {
name.as_str().to_string()
} else {
format!("arg{}", arg_index)
};
if Some(local) == mir.spread_arg {
// This argument (e.g., the last argument in the "rust-call" ABI)
// is a tuple that was spread at the ABI level and now we have
// to reconstruct it into a tuple local variable, from multiple
// individual LLVM function arguments.
let arg_ty = fx.monomorphize(&arg_decl.ty);
let tupled_arg_tys = match arg_ty.sty {
ty::Tuple(ref tys) => tys,
_ => bug!("spread argument isn't a tuple?!")
};
let place = PlaceRef::alloca(bx, bx.layout_of(arg_ty), &name);
for i in 0..tupled_arg_tys.len() {
let arg = &fx.fn_ty.args[idx];
idx += 1;
if arg.pad.is_some() {
llarg_idx += 1;
}
let pr_field = place.project_field(bx, i);
bx.store_fn_arg(arg, &mut llarg_idx, pr_field);
}
// Now that we have one alloca that contains the aggregate value,
// we can create one debuginfo entry for the argument.
arg_scope.map(|scope| {
let variable_access = VariableAccess::DirectVariable {
alloca: place.llval
};
bx.declare_local(
&fx.debug_context,
arg_decl.name.unwrap_or(kw::Invalid),
arg_ty, scope,
variable_access,
VariableKind::ArgumentVariable(arg_index + 1),
DUMMY_SP
);
});
return LocalRef::Place(place);
}
let arg = &fx.fn_ty.args[idx];
idx += 1;
if arg.pad.is_some() {
llarg_idx += 1;
}
if arg_scope.is_none() && !memory_locals.contains(local) {
// We don't have to cast or keep the argument in the alloca.
// FIXME(eddyb): We should figure out how to use llvm.dbg.value instead
// of putting everything in allocas just so we can use llvm.dbg.declare.
let local = |op| LocalRef::Operand(Some(op));
match arg.mode {
PassMode::Ignore(IgnoreMode::Zst) => {
return local(OperandRef::new_zst(bx, arg.layout));
}
PassMode::Ignore(IgnoreMode::CVarArgs) => {}
PassMode::Direct(_) => {
let llarg = bx.get_param(llarg_idx);
bx.set_value_name(llarg, &name);
llarg_idx += 1;
return local(
OperandRef::from_immediate_or_packed_pair(bx, llarg, arg.layout));
}
PassMode::Pair(..) => {
let a = bx.get_param(llarg_idx);
bx.set_value_name(a, &(name.clone() + ".0"));
llarg_idx += 1;
let b = bx.get_param(llarg_idx);
bx.set_value_name(b, &(name + ".1"));
llarg_idx += 1;
return local(OperandRef {
val: OperandValue::Pair(a, b),
layout: arg.layout
});
}
_ => {}
}
}
let place = if arg.is_sized_indirect() {
// Don't copy an indirect argument to an alloca, the caller
// already put it in a temporary alloca and gave it up.
// FIXME: lifetimes
let llarg = bx.get_param(llarg_idx);
bx.set_value_name(llarg, &name);
llarg_idx += 1;
PlaceRef::new_sized(llarg, arg.layout, arg.layout.align.abi)
} else if arg.is_unsized_indirect() {
// As the storage for the indirect argument lives during
// the whole function call, we just copy the fat pointer.
let llarg = bx.get_param(llarg_idx);
llarg_idx += 1;
let llextra = bx.get_param(llarg_idx);
llarg_idx += 1;
let indirect_operand = OperandValue::Pair(llarg, llextra);
let tmp = PlaceRef::alloca_unsized_indirect(bx, arg.layout, &name);
indirect_operand.store(bx, tmp);
tmp
} else {
let tmp = PlaceRef::alloca(bx, arg.layout, &name);
if fx.fn_ty.c_variadic && last_arg_idx.map(|idx| arg_index == idx).unwrap_or(false) {
let va_list_did = match tcx.lang_items().va_list() {
Some(did) => did,
None => bug!("`va_list` lang item required for C-variadic functions"),
};
match arg_decl.ty.sty {
ty::Adt(def, _) if def.did == va_list_did => {
// Call `va_start` on the spoofed `VaListImpl`.
bx.va_start(tmp.llval);
*va_list_ref = Some(tmp);
},
_ => bug!("last argument of variadic function is not a `va_list`")
}
} else {
bx.store_fn_arg(arg, &mut llarg_idx, tmp);
}
tmp
};
let upvar_debuginfo = &mir.__upvar_debuginfo_codegen_only_do_not_use;
arg_scope.map(|scope| {
// Is this a regular argument?
if arg_index > 0 || upvar_debuginfo.is_empty() {
// The Rust ABI passes indirect variables using a pointer and a manual copy, so we
// need to insert a deref here, but the C ABI uses a pointer and a copy using the
// byval attribute, for which LLVM always does the deref itself,
// so we must not add it.
let variable_access = VariableAccess::DirectVariable {
alloca: place.llval
};
bx.declare_local(
&fx.debug_context,
arg_decl.name.unwrap_or(kw::Invalid),
arg.layout.ty,
scope,
variable_access,
VariableKind::ArgumentVariable(arg_index + 1),
DUMMY_SP
);
return;
}
let pin_did = tcx.lang_items().pin_type();
// Or is it the closure environment?
let (closure_layout, env_ref) = match arg.layout.ty.sty {
ty::RawPtr(ty::TypeAndMut { ty, .. }) |
ty::Ref(_, ty, _) => (bx.layout_of(ty), true),
ty::Adt(def, substs) if Some(def.did) == pin_did => {
match substs.type_at(0).sty {
ty::Ref(_, ty, _) => (bx.layout_of(ty), true),
_ => (arg.layout, false),
}
}
_ => (arg.layout, false)
};
let (def_id, upvar_substs) = match closure_layout.ty.sty {
ty::Closure(def_id, substs) => (def_id, UpvarSubsts::Closure(substs)),
ty::Generator(def_id, substs, _) => (def_id, UpvarSubsts::Generator(substs)),
_ => bug!("upvar debuginfo with non-closure arg0 type `{}`", closure_layout.ty)
};
let upvar_tys = upvar_substs.upvar_tys(def_id, tcx);
let extra_locals = {
let upvars = upvar_debuginfo
.iter()
.zip(upvar_tys)
.enumerate()
.map(|(i, (upvar, ty))| {
(None, i, upvar.debug_name, upvar.by_ref, ty, scope, DUMMY_SP)
});
let generator_fields = mir.generator_layout.as_ref().map(|generator_layout| {
let (def_id, gen_substs) = match closure_layout.ty.sty {
ty::Generator(def_id, substs, _) => (def_id, substs),
_ => bug!("generator layout without generator substs"),
};
let state_tys = gen_substs.state_tys(def_id, tcx);
generator_layout.variant_fields.iter()
.zip(state_tys)
.enumerate()
.flat_map(move |(variant_idx, (fields, tys))| {
let variant_idx = Some(VariantIdx::from(variant_idx));
fields.iter()
.zip(tys)
.enumerate()
.filter_map(move |(i, (field, ty))| {
let decl = &generator_layout.
__local_debuginfo_codegen_only_do_not_use[*field];
if let Some(name) = decl.name {
let ty = fx.monomorphize(&ty);
let (var_scope, var_span) = fx.debug_loc(mir::SourceInfo {
span: decl.source_info.span,
scope: decl.visibility_scope,
});
let var_scope = var_scope.unwrap_or(scope);
Some((variant_idx, i, name, false, ty, var_scope, var_span))
} else {
None
}
})
})
}).into_iter().flatten();
upvars.chain(generator_fields)
};
for (variant_idx, field, name, by_ref, ty, var_scope, var_span) in extra_locals {
let fields = match variant_idx {
Some(variant_idx) => {
match &closure_layout.variants {
Variants::Multiple { variants, .. } => {
&variants[variant_idx].fields
},
_ => bug!("variant index on univariant layout"),
}
}
None => &closure_layout.fields,
};
let byte_offset_of_var_in_env = fields.offset(field).bytes();
let ops = bx.debuginfo_upvar_ops_sequence(byte_offset_of_var_in_env);
// The environment and the capture can each be indirect.
let mut ops = if env_ref { &ops[..] } else { &ops[1..] };
let ty = if let (true, &ty::Ref(_, ty, _)) = (by_ref, &ty.sty) {
ty
} else {
ops = &ops[..ops.len() - 1];
ty
};
let variable_access = VariableAccess::IndirectVariable {
alloca: place.llval,
address_operations: &ops
};
bx.declare_local(
&fx.debug_context,
name,
ty,
var_scope,
variable_access,
VariableKind::LocalVariable,
var_span
);
}
});
if arg.is_unsized_indirect() {
LocalRef::UnsizedPlace(place)
} else {
LocalRef::Place(place)
}
}).collect()
}
mod analyze;
mod block;
pub mod constant;
pub mod place;
pub mod operand;
mod rvalue;
mod statement;
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