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Convert the legalizer/boundary module to FuncCursor.

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This is a larger refactoring because all the changes need to be done
together. Either you pass a Function reference around, or you pass
around references to the parts. There is no in between.
This commit is contained in:
Jakob Stoklund Olesen
2017-09-21 16:43:47 -07:00
parent 85e4e9f511
commit a9acbd1afd
1 changed files with 163 additions and 164 deletions
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283
lib/cretonne/src/legalizer/boundary.rs
View File

@@ -18,10 +18,10 @@
//! intermediate state doesn't type check.
use abi::{legalize_abi_value, ValueConversion};
use cursor::{Cursor, FuncCursor};
use flowgraph::ControlFlowGraph;
use ir::{Function, Cursor, CursorBase, DataFlowGraph, Inst, InstBuilder, Ebb, Type, Value,
Signature, SigRef, ArgumentType, ArgumentPurpose, ArgumentLoc, ValueLoc, ValueLocations,
StackSlots, StackSlotKind};
use ir::{Function, DataFlowGraph, Inst, InstBuilder, Ebb, Type, Value, Signature, SigRef,
ArgumentType, ArgumentPurpose, ArgumentLoc, ValueLoc, StackSlotKind};
use ir::instructions::CallInfo;
use isa::TargetIsa;
use legalizer::split::{isplit, vsplit};
@@ -62,25 +62,25 @@ fn legalize_entry_arguments(func: &mut Function, entry: Ebb) {
// Insert position for argument conversion code.
// We want to insert instructions before the first instruction in the entry block.
// If the entry block is empty, append instructions to it instead.
let mut pos = Cursor::new(&mut func.layout, &mut func.srclocs).at_first_inst(entry);
let mut pos = FuncCursor::new(func).at_first_inst(entry);
// Keep track of the argument types in the ABI-legalized signature.
let abi_types = &func.signature.argument_types;
let mut abi_arg = 0;
// Process the EBB arguments one at a time, possibly replacing one argument with multiple new
// ones. We do this by detaching the entry EBB arguments first.
let ebb_args = func.dfg.detach_ebb_args(entry);
let ebb_args = pos.func.dfg.detach_ebb_args(entry);
let mut old_arg = 0;
while let Some(arg) = ebb_args.get(old_arg, &func.dfg.value_lists) {
while let Some(arg) = ebb_args.get(old_arg, &pos.func.dfg.value_lists) {
old_arg += 1;
let arg_type = func.dfg.value_type(arg);
if arg_type == abi_types[abi_arg].value_type {
let abi_type = pos.func.signature.argument_types[abi_arg];
let arg_type = pos.func.dfg.value_type(arg);
if arg_type == abi_type.value_type {
// No value translation is necessary, this argument matches the ABI type.
// Just use the original EBB argument value. This is the most common case.
func.dfg.attach_ebb_arg(entry, arg);
match abi_types[abi_arg].purpose {
pos.func.dfg.attach_ebb_arg(entry, arg);
match abi_type.purpose {
ArgumentPurpose::Normal => {}
ArgumentPurpose::StructReturn => {
assert!(!has_sret, "Multiple sret arguments found");
@@ -94,13 +94,13 @@ fn legalize_entry_arguments(func: &mut Function, entry: Ebb) {
assert!(!has_sigid, "Multiple sigid arguments found");
has_sigid = true;
}
_ => panic!("Unexpected special-purpose arg {}", abi_types[abi_arg]),
_ => panic!("Unexpected special-purpose arg {}", abi_type),
}
abi_arg += 1;
} else {
// Compute the value we want for `arg` from the legalized ABI arguments.
let mut get_arg = |dfg: &mut DataFlowGraph, ty| {
let abi_type = abi_types[abi_arg];
let mut get_arg = |func: &mut Function, ty| {
let abi_type = func.signature.argument_types[abi_arg];
assert_eq!(
abi_type.purpose,
ArgumentPurpose::Normal,
@@ -108,22 +108,21 @@ fn legalize_entry_arguments(func: &mut Function, entry: Ebb) {
);
if ty == abi_type.value_type {
abi_arg += 1;
Ok(dfg.append_ebb_arg(entry, ty))
Ok(func.dfg.append_ebb_arg(entry, ty))
} else {
Err(abi_type)
}
};
let converted =
convert_from_abi(&mut func.dfg, &mut pos, arg_type, Some(arg), &mut get_arg);
let converted = convert_from_abi(&mut pos, arg_type, Some(arg), &mut get_arg);
// The old `arg` is no longer an attached EBB argument, but there are probably still
// uses of the value.
assert_eq!(func.dfg.resolve_aliases(arg), converted);
assert_eq!(pos.func.dfg.resolve_aliases(arg), converted);
}
}
// The legalized signature may contain additional arguments representing special-purpose
// registers.
for &arg in &abi_types[abi_arg..] {
for &arg in &pos.func.signature.argument_types[abi_arg..] {
match arg.purpose {
// Any normal arguments should have been processed above.
ArgumentPurpose::Normal => {
@@ -156,7 +155,7 @@ fn legalize_entry_arguments(func: &mut Function, entry: Ebb) {
// Just create entry block values to match here. We will use them in `handle_return_abi()`
// below.
func.dfg.append_ebb_arg(entry, arg.value_type);
pos.func.dfg.append_ebb_arg(entry, arg.value_type);
}
}
@@ -168,13 +167,9 @@ fn legalize_entry_arguments(func: &mut Function, entry: Ebb) {
/// This function is very similar to the `legalize_entry_arguments` function above.
///
/// Returns the possibly new instruction representing the call.
fn legalize_inst_results<ResType>(
dfg: &mut DataFlowGraph,
pos: &mut Cursor,
mut get_abi_type: ResType,
) -> Inst
fn legalize_inst_results<ResType>(pos: &mut FuncCursor, mut get_abi_type: ResType) -> Inst
where
ResType: FnMut(&DataFlowGraph, usize) -> ArgumentType,
ResType: FnMut(&Function, usize) -> ArgumentType,
{
let call = pos.current_inst().expect(
"Cursor must point to a call instruction",
@@ -182,37 +177,37 @@ where
// We theoretically allow for call instructions that return a number of fixed results before
// the call return values. In practice, it doesn't happen.
let fixed_results = dfg[call].opcode().constraints().fixed_results();
let fixed_results = pos.func.dfg[call].opcode().constraints().fixed_results();
assert_eq!(fixed_results, 0, "Fixed results on calls not supported");
let results = dfg.detach_results(call);
let results = pos.func.dfg.detach_results(call);
let mut next_res = 0;
let mut abi_res = 0;
// Point immediately after the call.
pos.next_inst();
while let Some(res) = results.get(next_res, &dfg.value_lists) {
while let Some(res) = results.get(next_res, &pos.func.dfg.value_lists) {
next_res += 1;
let res_type = dfg.value_type(res);
if res_type == get_abi_type(dfg, abi_res).value_type {
let res_type = pos.func.dfg.value_type(res);
if res_type == get_abi_type(pos.func, abi_res).value_type {
// No value translation is necessary, this result matches the ABI type.
dfg.attach_result(call, res);
pos.func.dfg.attach_result(call, res);
abi_res += 1;
} else {
let mut get_res = |dfg: &mut DataFlowGraph, ty| {
let abi_type = get_abi_type(dfg, abi_res);
let mut get_res = |func: &mut Function, ty| {
let abi_type = get_abi_type(func, abi_res);
if ty == abi_type.value_type {
let last_res = dfg.append_result(call, ty);
let last_res = func.dfg.append_result(call, ty);
abi_res += 1;
Ok(last_res)
} else {
Err(abi_type)
}
};
let v = convert_from_abi(dfg, pos, res_type, Some(res), &mut get_res);
assert_eq!(dfg.resolve_aliases(res), v);
let v = convert_from_abi(pos, res_type, Some(res), &mut get_res);
assert_eq!(pos.func.dfg.resolve_aliases(res), v);
}
}
@@ -229,19 +224,18 @@ where
///
/// If the `into_result` value is provided, the converted result will be written into that value.
fn convert_from_abi<GetArg>(
dfg: &mut DataFlowGraph,
pos: &mut Cursor,
pos: &mut FuncCursor,
ty: Type,
into_result: Option<Value>,
get_arg: &mut GetArg,
) -> Value
where
GetArg: FnMut(&mut DataFlowGraph, Type) -> Result<Value, ArgumentType>,
GetArg: FnMut(&mut Function, Type) -> Result<Value, ArgumentType>,
{
// Terminate the recursion when we get the desired type.
let arg_type = match get_arg(dfg, ty) {
let arg_type = match get_arg(pos.func, ty) {
Ok(v) => {
debug_assert_eq!(dfg.value_type(v), ty);
debug_assert_eq!(pos.func.dfg.value_type(v), ty);
assert_eq!(into_result, None);
return v;
}
@@ -258,45 +252,45 @@ where
// Construct a `ty` by concatenating two ABI integers.
ValueConversion::IntSplit => {
let abi_ty = ty.half_width().expect("Invalid type for conversion");
let lo = convert_from_abi(dfg, pos, abi_ty, None, get_arg);
let hi = convert_from_abi(dfg, pos, abi_ty, None, get_arg);
let lo = convert_from_abi(pos, abi_ty, None, get_arg);
let hi = convert_from_abi(pos, abi_ty, None, get_arg);
dbg!(
"intsplit {}: {}, {}: {}",
lo,
dfg.value_type(lo),
pos.func.dfg.value_type(lo),
hi,
dfg.value_type(hi)
pos.func.dfg.value_type(hi)
);
dfg.ins(pos).with_results([into_result]).iconcat(lo, hi)
pos.ins().with_results([into_result]).iconcat(lo, hi)
}
// Construct a `ty` by concatenating two halves of a vector.
ValueConversion::VectorSplit => {
let abi_ty = ty.half_vector().expect("Invalid type for conversion");
let lo = convert_from_abi(dfg, pos, abi_ty, None, get_arg);
let hi = convert_from_abi(dfg, pos, abi_ty, None, get_arg);
dfg.ins(pos).with_results([into_result]).vconcat(lo, hi)
let lo = convert_from_abi(pos, abi_ty, None, get_arg);
let hi = convert_from_abi(pos, abi_ty, None, get_arg);
pos.ins().with_results([into_result]).vconcat(lo, hi)
}
// Construct a `ty` by bit-casting from an integer type.
ValueConversion::IntBits => {
assert!(!ty.is_int());
let abi_ty = Type::int(ty.bits()).expect("Invalid type for conversion");
let arg = convert_from_abi(dfg, pos, abi_ty, None, get_arg);
dfg.ins(pos).with_results([into_result]).bitcast(ty, arg)
let arg = convert_from_abi(pos, abi_ty, None, get_arg);
pos.ins().with_results([into_result]).bitcast(ty, arg)
}
// ABI argument is a sign-extended version of the value we want.
ValueConversion::Sext(abi_ty) => {
let arg = convert_from_abi(dfg, pos, abi_ty, None, get_arg);
let arg = convert_from_abi(pos, abi_ty, None, get_arg);
// TODO: Currently, we don't take advantage of the ABI argument being sign-extended.
// We could insert an `assert_sreduce` which would fold with a following `sextend` of
// this value.
dfg.ins(pos).with_results([into_result]).ireduce(ty, arg)
pos.ins().with_results([into_result]).ireduce(ty, arg)
}
ValueConversion::Uext(abi_ty) => {
let arg = convert_from_abi(dfg, pos, abi_ty, None, get_arg);
let arg = convert_from_abi(pos, abi_ty, None, get_arg);
// TODO: Currently, we don't take advantage of the ABI argument being sign-extended.
// We could insert an `assert_ureduce` which would fold with a following `uextend` of
// this value.
dfg.ins(pos).with_results([into_result]).ireduce(ty, arg)
pos.ins().with_results([into_result]).ireduce(ty, arg)
}
}
}
@@ -313,48 +307,47 @@ where
/// return the `Err(ArgumentType)` that is needed.
///
fn convert_to_abi<PutArg>(
dfg: &mut DataFlowGraph,
pos: &mut FuncCursor,
cfg: &ControlFlowGraph,
pos: &mut Cursor,
value: Value,
put_arg: &mut PutArg,
) where
PutArg: FnMut(&mut DataFlowGraph, Value) -> Result<(), ArgumentType>,
PutArg: FnMut(&mut Function, Value) -> Result<(), ArgumentType>,
{
// Start by invoking the closure to either terminate the recursion or get the argument type
// we're trying to match.
let arg_type = match put_arg(dfg, value) {
let arg_type = match put_arg(pos.func, value) {
Ok(_) => return,
Err(t) => t,
};
let ty = dfg.value_type(value);
let ty = pos.func.dfg.value_type(value);
match legalize_abi_value(ty, &arg_type) {
ValueConversion::IntSplit => {
let curpos = pos.position();
let (lo, hi) = isplit(dfg, pos.layout, cfg, curpos, value);
convert_to_abi(dfg, cfg, pos, lo, put_arg);
convert_to_abi(dfg, cfg, pos, hi, put_arg);
let (lo, hi) = isplit(&mut pos.func.dfg, &mut pos.func.layout, cfg, curpos, value);
convert_to_abi(pos, cfg, lo, put_arg);
convert_to_abi(pos, cfg, hi, put_arg);
}
ValueConversion::VectorSplit => {
let curpos = pos.position();
let (lo, hi) = vsplit(dfg, pos.layout, cfg, curpos, value);
convert_to_abi(dfg, cfg, pos, lo, put_arg);
convert_to_abi(dfg, cfg, pos, hi, put_arg);
let (lo, hi) = vsplit(&mut pos.func.dfg, &mut pos.func.layout, cfg, curpos, value);
convert_to_abi(pos, cfg, lo, put_arg);
convert_to_abi(pos, cfg, hi, put_arg);
}
ValueConversion::IntBits => {
assert!(!ty.is_int());
let abi_ty = Type::int(ty.bits()).expect("Invalid type for conversion");
let arg = dfg.ins(pos).bitcast(abi_ty, value);
convert_to_abi(dfg, cfg, pos, arg, put_arg);
let arg = pos.ins().bitcast(abi_ty, value);
convert_to_abi(pos, cfg, arg, put_arg);
}
ValueConversion::Sext(abi_ty) => {
let arg = dfg.ins(pos).sextend(abi_ty, value);
convert_to_abi(dfg, cfg, pos, arg, put_arg);
let arg = pos.ins().sextend(abi_ty, value);
convert_to_abi(pos, cfg, arg, put_arg);
}
ValueConversion::Uext(abi_ty) => {
let arg = dfg.ins(pos).uextend(abi_ty, value);
convert_to_abi(dfg, cfg, pos, arg, put_arg);
let arg = pos.ins().uextend(abi_ty, value);
convert_to_abi(pos, cfg, arg, put_arg);
}
}
}
@@ -402,28 +395,30 @@ fn check_return_signature(dfg: &DataFlowGraph, inst: Inst, sig: &Signature) -> b
/// argument number in `0..abi_args`.
///
fn legalize_inst_arguments<ArgType>(
dfg: &mut DataFlowGraph,
pos: &mut FuncCursor,
cfg: &ControlFlowGraph,
pos: &mut Cursor,
abi_args: usize,
mut get_abi_type: ArgType,
) where
ArgType: FnMut(&DataFlowGraph, usize) -> ArgumentType,
ArgType: FnMut(&Function, usize) -> ArgumentType,
{
let inst = pos.current_inst().expect(
"Cursor must point to a call instruction",
);
// Lift the value list out of the call instruction so we modify it.
let mut vlist = dfg[inst].take_value_list().expect(
let mut vlist = pos.func.dfg[inst].take_value_list().expect(
"Call must have a value list",
);
// The value list contains all arguments to the instruction, including the callee on an
// indirect call which isn't part of the call arguments that must match the ABI signature.
// Figure out how many fixed values are at the front of the list. We won't touch those.
let fixed_values = dfg[inst].opcode().constraints().fixed_value_arguments();
let have_args = vlist.len(&dfg.value_lists) - fixed_values;
let fixed_values = pos.func.dfg[inst]
.opcode()
.constraints()
.fixed_value_arguments();
let have_args = vlist.len(&pos.func.dfg.value_lists) - fixed_values;
// Grow the value list to the right size and shift all the existing arguments to the right.
// This lets us write the new argument values into the list without overwriting the old
@@ -450,30 +445,34 @@ fn legalize_inst_arguments<ArgType>(
// <------------------> abi_args
// [FFFFNNNNNNNNNNNNNNNNNNNN]
//
vlist.grow_at(fixed_values, abi_args - have_args, &mut dfg.value_lists);
vlist.grow_at(
fixed_values,
abi_args - have_args,
&mut pos.func.dfg.value_lists,
);
let old_arg_offset = fixed_values + abi_args - have_args;
let mut abi_arg = 0;
for old_arg in 0..have_args {
let old_value = vlist
.get(old_arg_offset + old_arg, &dfg.value_lists)
.get(old_arg_offset + old_arg, &pos.func.dfg.value_lists)
.unwrap();
let mut put_arg = |dfg: &mut DataFlowGraph, arg| {
let abi_type = get_abi_type(dfg, abi_arg);
if dfg.value_type(arg) == abi_type.value_type {
let mut put_arg = |func: &mut Function, arg| {
let abi_type = get_abi_type(func, abi_arg);
if func.dfg.value_type(arg) == abi_type.value_type {
// This is the argument type we need.
vlist.as_mut_slice(&mut dfg.value_lists)[fixed_values + abi_arg] = arg;
vlist.as_mut_slice(&mut func.dfg.value_lists)[fixed_values + abi_arg] = arg;
abi_arg += 1;
Ok(())
} else {
Err(abi_type)
}
};
convert_to_abi(dfg, cfg, pos, old_value, &mut put_arg);
convert_to_abi(pos, cfg, old_value, &mut put_arg);
}
// Put the modified value list back.
dfg[inst].put_value_list(vlist);
pos.func.dfg[inst].put_value_list(vlist);
}
/// Insert ABI conversion code before and after the call instruction at `pos`.
@@ -487,39 +486,38 @@ fn legalize_inst_arguments<ArgType>(
///
/// Returns `true` if any instructions were inserted.
pub fn handle_call_abi(mut inst: Inst, func: &mut Function, cfg: &ControlFlowGraph) -> bool {
let dfg = &mut func.dfg;
let pos = &mut Cursor::new(&mut func.layout, &mut func.srclocs).at_inst(inst);
let pos = &mut FuncCursor::new(func).at_inst(inst);
pos.use_srcloc(inst);
// Start by checking if the argument types already match the signature.
let sig_ref = match check_call_signature(dfg, inst) {
Ok(_) => return spill_call_arguments(dfg, &mut func.locations, &mut func.stack_slots, pos),
let sig_ref = match check_call_signature(&pos.func.dfg, inst) {
Ok(_) => return spill_call_arguments(pos),
Err(s) => s,
};
// OK, we need to fix the call arguments to match the ABI signature.
let abi_args = dfg.signatures[sig_ref].argument_types.len();
legalize_inst_arguments(dfg, cfg, pos, abi_args, |dfg, abi_arg| {
dfg.signatures[sig_ref].argument_types[abi_arg]
let abi_args = pos.func.dfg.signatures[sig_ref].argument_types.len();
legalize_inst_arguments(pos, cfg, abi_args, |func, abi_arg| {
func.dfg.signatures[sig_ref].argument_types[abi_arg]
});
if !dfg.signatures[sig_ref].return_types.is_empty() {
inst = legalize_inst_results(dfg, pos, |dfg, abi_res| {
dfg.signatures[sig_ref].return_types[abi_res]
if !pos.func.dfg.signatures[sig_ref].return_types.is_empty() {
inst = legalize_inst_results(pos, |func, abi_res| {
func.dfg.signatures[sig_ref].return_types[abi_res]
});
}
debug_assert!(
check_call_signature(dfg, inst).is_ok(),
check_call_signature(&pos.func.dfg, inst).is_ok(),
"Signature still wrong: {}, {}{}",
dfg.display_inst(inst, None),
pos.func.dfg.display_inst(inst, None),
sig_ref,
dfg.signatures[sig_ref]
pos.func.dfg.signatures[sig_ref]
);
// Go back and insert spills for any stack arguments.
pos.goto_inst(inst);
spill_call_arguments(dfg, &mut func.locations, &mut func.stack_slots, pos);
spill_call_arguments(pos);
// Yes, we changed stuff.
true
@@ -529,19 +527,15 @@ pub fn handle_call_abi(mut inst: Inst, func: &mut Function, cfg: &ControlFlowGra
///
/// Return `true` if any instructions were inserted.
pub fn handle_return_abi(inst: Inst, func: &mut Function, cfg: &ControlFlowGraph) -> bool {
let dfg = &mut func.dfg;
let sig = &mut func.signature;
let pos = &mut Cursor::new(&mut func.layout, &mut func.srclocs).at_inst(inst);
pos.use_srcloc(inst);
// Check if the returned types already match the signature.
if check_return_signature(dfg, inst, sig) {
if check_return_signature(&func.dfg, inst, &func.signature) {
return false;
}
// Count the special-purpose return values (`link`, `sret`, and `vmctx`) that were appended to
// the legalized signature.
let special_args = sig.return_types
let special_args = func.signature
.return_types
.iter()
.rev()
.take_while(|&rt| {
@@ -549,16 +543,15 @@ pub fn handle_return_abi(inst: Inst, func: &mut Function, cfg: &ControlFlowGraph
rt.purpose == ArgumentPurpose::VMContext
})
.count();
let abi_args = func.signature.return_types.len() - special_args;
let abi_args = sig.return_types.len() - special_args;
legalize_inst_arguments(
dfg,
cfg,
pos,
abi_args,
|_, abi_arg| sig.return_types[abi_arg],
);
assert_eq!(dfg.inst_variable_args(inst).len(), abi_args);
let pos = &mut FuncCursor::new(func).at_inst(inst);
pos.use_srcloc(inst);
legalize_inst_arguments(pos, cfg, abi_args, |func, abi_arg| {
func.signature.return_types[abi_arg]
});
assert_eq!(pos.func.dfg.inst_variable_args(inst).len(), abi_args);
// Append special return arguments for any `sret`, `link`, and `vmctx` return values added to
// the legalized signature. These values should simply be propagated from the entry block
@@ -567,10 +560,10 @@ pub fn handle_return_abi(inst: Inst, func: &mut Function, cfg: &ControlFlowGraph
dbg!(
"Adding {} special-purpose arguments to {}",
special_args,
dfg.display_inst(inst, None)
pos.func.dfg.display_inst(inst, None)
);
let mut vlist = dfg[inst].take_value_list().unwrap();
for arg in &sig.return_types[abi_args..] {
let mut vlist = pos.func.dfg[inst].take_value_list().unwrap();
for arg in &pos.func.signature.return_types[abi_args..] {
match arg.purpose {
ArgumentPurpose::Link |
ArgumentPurpose::StructReturn |
@@ -581,24 +574,29 @@ pub fn handle_return_abi(inst: Inst, func: &mut Function, cfg: &ControlFlowGraph
// A `link`/`sret`/`vmctx` return value can only appear in a signature that has a
// unique matching argument. They are appended at the end, so search the signature from
// the end.
let idx = sig.argument_types
let idx = pos.func
.signature
.argument_types
.iter()
.rposition(|t| t.purpose == arg.purpose)
.expect("No matching special purpose argument.");
// Get the corresponding entry block value and add it to the return instruction's
// arguments.
let val = dfg.ebb_args(pos.layout.entry_block().unwrap())[idx];
debug_assert_eq!(dfg.value_type(val), arg.value_type);
vlist.push(val, &mut dfg.value_lists);
let val = pos.func.dfg.ebb_args(
pos.func.layout.entry_block().unwrap(),
)
[idx];
debug_assert_eq!(pos.func.dfg.value_type(val), arg.value_type);
vlist.push(val, &mut pos.func.dfg.value_lists);
}
dfg[inst].put_value_list(vlist);
pos.func.dfg[inst].put_value_list(vlist);
}
debug_assert!(
check_return_signature(dfg, inst, sig),
check_return_signature(&pos.func.dfg, inst, &pos.func.signature),
"Signature still wrong: {} / signature {}",
dfg.display_inst(inst, None),
sig
pos.func.dfg.display_inst(inst, None),
pos.func.signature
);
// Yes, we changed stuff.
@@ -629,24 +627,24 @@ fn spill_entry_arguments(func: &mut Function, entry: Ebb) {
/// TODO: The outgoing stack slots can be written a bit earlier, as long as there are no branches
/// or calls between writing the stack slots and the call instruction. Writing the slots earlier
/// could help reduce register pressure before the call.
fn spill_call_arguments(
dfg: &mut DataFlowGraph,
locations: &mut ValueLocations,
stack_slots: &mut StackSlots,
pos: &mut Cursor,
) -> bool {
fn spill_call_arguments(pos: &mut FuncCursor) -> bool {
let inst = pos.current_inst().expect(
"Cursor must point to a call instruction",
);
let sig_ref = dfg.call_signature(inst).expect(
let sig_ref = pos.func.dfg.call_signature(inst).expect(
"Call instruction expected.",
);
// Start by building a list of stack slots and arguments to be replaced.
// This requires borrowing `dfg`, so we can't change anything.
let arglist = dfg.inst_variable_args(inst)
// This requires borrowing `pos.func.dfg`, so we can't change anything.
let arglist = {
let locations = &pos.func.locations;
let stack_slots = &mut pos.func.stack_slots;
pos.func
.dfg
.inst_variable_args(inst)
.iter()
.zip(&dfg.signatures[sig_ref].argument_types)
.zip(&pos.func.dfg.signatures[sig_ref].argument_types)
.enumerate()
.filter_map(|(idx, (&arg, abi))| {
match abi.location {
@@ -671,7 +669,8 @@ fn spill_call_arguments(
_ => None,
}
})
.collect::<Vec<_>>();
.collect::<Vec<_>>()
};
if arglist.is_empty() {
return false;
@@ -679,9 +678,9 @@ fn spill_call_arguments(
// Insert the spill instructions and rewrite call arguments.
for (idx, arg, ss) in arglist {
let stack_val = dfg.ins(pos).spill(arg);
locations[stack_val] = ValueLoc::Stack(ss);
dfg.inst_variable_args_mut(inst)[idx] = stack_val;
let stack_val = pos.ins().spill(arg);
pos.func.locations[stack_val] = ValueLoc::Stack(ss);
pos.func.dfg.inst_variable_args_mut(inst)[idx] = stack_val;
}
// We changed stuff.