@ -520,7 +520,7 @@ pub trait ABIMachineSpec {
/// ABI information shared between body (callee) and caller.
#[ derive(Clone) ]
struct ABISig {
pub struct ABISig {
/// Argument locations (regs or stack slots). Stack offsets are relative to
/// SP on entry to function.
args : Vec < ABIArg > ,
@ -533,15 +533,21 @@ struct ABISig {
stack_ret_space : i64 ,
/// Index in `args` of the stack-return-value-area argument.
stack_ret_arg : Option < usize > ,
/// Specific order for copying into arguments at callsites. We must be
/// careful to copy into StructArgs first, because we need to be able
/// to invoke memcpy() before we've loaded other arg regs (see above).
copy_to_arg_order : SmallVec < [ usize ; 8 ] > ,
/// Calling convention used.
call_conv : isa ::CallConv ,
}
impl ABISig {
fn from_func_sig < M : ABIMachineSpec > (
pub fn from_func_sig < M : ABIMachineSpec > (
sig : & ir ::Signature ,
flags : & settings ::Flags ,
) -> CodegenResult < ABISig > {
let sig = ensure_struct_return_ptr_is_returned ( sig ) ;
// Compute args and retvals from signature. Handle retvals first,
// because we may need to add a return-area arg to the args.
let ( rets , stack_ret_space , _ ) = M ::compute_arg_locs (
@ -560,14 +566,30 @@ impl ABISig {
need_stack_return_area ,
) ? ;
let mut copy_to_arg_order = SmallVec ::new ( ) ;
for ( i , arg ) in args . iter ( ) . enumerate ( ) {
// Struct args.
if arg . is_struct_arg ( ) {
copy_to_arg_order . push ( i ) ;
}
}
for ( i , arg ) in args . iter ( ) . enumerate ( ) {
// Non-struct args. Skip an appended return-area arg for multivalue
// returns, if any.
if ! arg . is_struct_arg ( ) & & i < sig . params . len ( ) {
copy_to_arg_order . push ( i ) ;
}
}
log ::trace ! (
"ABISig: sig {:?} => args = {:?} rets = {:?} arg stack = {} ret stack = {} stack_ret_arg = {:?}" ,
"ABISig: sig {:?} => args = {:?} rets = {:?} arg stack = {} ret stack = {} stack_ret_arg = {:?} copy_to_arg_order = {:?} " ,
sig ,
args ,
rets ,
stack_arg_space ,
stack_ret_space ,
stack_ret_arg
stack_ret_arg ,
copy_to_arg_order ,
) ;
Ok ( ABISig {
@ -576,9 +598,99 @@ impl ABISig {
stack_arg_space ,
stack_ret_space ,
stack_ret_arg ,
copy_to_arg_order ,
call_conv : sig . call_conv ,
} )
}
/// Return all uses (i.e, function args), defs (i.e., return values
/// and caller-saved registers), and clobbers for the callsite.
pub fn call_uses_defs_clobbers < M : ABIMachineSpec > (
& self ,
) -> ( SmallVec < [ Reg ; 8 ] > , SmallVec < [ Writable < Reg > ; 8 ] > , PRegSet ) {
// Compute uses: all arg regs.
let mut uses = smallvec ! [ ] ;
for arg in & self . args {
if let & ABIArg ::Slots { ref slots , . . } = arg {
for slot in slots {
match slot {
& ABIArgSlot ::Reg { reg , . . } = > {
uses . push ( Reg ::from ( reg ) ) ;
}
_ = > { }
}
}
}
}
// Get clobbers: all caller-saves. These may include return value
// regs, which we will remove from the clobber set below.
let mut clobbers = M ::get_regs_clobbered_by_call ( self . call_conv ) ;
// Compute defs: all retval regs, and all caller-save (clobbered) regs.
let mut defs = smallvec ! [ ] ;
for ret in & self . rets {
if let & ABIArg ::Slots { ref slots , . . } = ret {
for slot in slots {
match slot {
& ABIArgSlot ::Reg { reg , . . } = > {
defs . push ( Writable ::from_reg ( Reg ::from ( reg ) ) ) ;
clobbers . remove ( PReg ::from ( reg ) ) ;
}
_ = > { }
}
}
}
}
( uses , defs , clobbers )
}
/// Specific order for copying into arguments at callsites.
pub fn copy_to_arg_order ( & self , idx : usize ) -> usize {
self . copy_to_arg_order [ idx ]
}
/// Get the number of arguments expected.
pub fn num_args ( & self ) -> usize {
if self . stack_ret_arg . is_some ( ) {
self . args . len ( ) - 1
} else {
self . args . len ( )
}
}
/// Get information specifying how to pass one argument.
pub fn get_arg ( & self , idx : usize ) -> ABIArg {
self . args [ idx ] . clone ( )
}
/// Get total stack space required for arguments.
pub fn stack_arg_space ( & self ) -> i64 {
self . stack_arg_space
}
/// Get the number of return values expected.
pub fn num_rets ( & self ) -> usize {
self . rets . len ( )
}
/// Get information specifying how to pass one return value.
pub fn get_ret ( & self , idx : usize ) -> ABIArg {
self . rets [ idx ] . clone ( )
}
/// Get total stack space required for return values.
pub fn stack_ret_space ( & self ) -> i64 {
self . stack_ret_space
}
/// Get information specifying how to pass the implicit pointer
/// to the return-value area on the stack, if required.
pub fn get_ret_arg ( & self ) -> Option < ABIArg > {
let ret_arg = self . stack_ret_arg ? ;
Some ( self . args [ ret_arg ] . clone ( ) )
}
}
/// ABI object for a function body.
@ -1357,47 +1469,6 @@ impl<M: ABIMachineSpec> ABICallee for ABICalleeImpl<M> {
}
}
fn abisig_to_uses_defs_clobbers < M : ABIMachineSpec > (
sig : & ABISig ,
) -> ( SmallVec < [ Reg ; 8 ] > , SmallVec < [ Writable < Reg > ; 8 ] > , PRegSet ) {
// Compute uses: all arg regs.
let mut uses = smallvec ! [ ] ;
for arg in & sig . args {
if let & ABIArg ::Slots { ref slots , . . } = arg {
for slot in slots {
match slot {
& ABIArgSlot ::Reg { reg , . . } = > {
uses . push ( Reg ::from ( reg ) ) ;
}
_ = > { }
}
}
}
}
// Get clobbers: all caller-saves. These may include return value
// regs, which we will remove from the clobber set below.
let mut clobbers = M ::get_regs_clobbered_by_call ( sig . call_conv ) ;
// Compute defs: all retval regs, and all caller-save (clobbered) regs.
let mut defs = smallvec ! [ ] ;
for ret in & sig . rets {
if let & ABIArg ::Slots { ref slots , . . } = ret {
for slot in slots {
match slot {
& ABIArgSlot ::Reg { reg , . . } = > {
defs . push ( Writable ::from_reg ( Reg ::from ( reg ) ) ) ;
clobbers . remove ( PReg ::from ( reg ) ) ;
}
_ = > { }
}
}
}
}
( uses , defs , clobbers )
}
/// ABI object for a callsite.
pub struct ABICallerImpl < M : ABIMachineSpec > {
/// CLIF-level signature, possibly normalized.
@ -1442,7 +1513,7 @@ impl<M: ABIMachineSpec> ABICallerImpl<M> {
) -> CodegenResult < ABICallerImpl < M > > {
let ir_sig = ensure_struct_return_ptr_is_returned ( sig ) ;
let sig = ABISig ::from_func_sig ::< M > ( & ir_sig , flags ) ? ;
let ( uses , defs , clobbers ) = abisig_to _uses_defs_clobbers< M > ( & sig ) ;
let ( uses , defs , clobbers ) = sig . call _uses_defs_clobbers< M > ( ) ;
Ok ( ABICallerImpl {
ir_sig ,
sig ,
@ -1468,7 +1539,7 @@ impl<M: ABIMachineSpec> ABICallerImpl<M> {
) -> CodegenResult < ABICallerImpl < M > > {
let ir_sig = ensure_struct_return_ptr_is_returned ( sig ) ;
let sig = ABISig ::from_func_sig ::< M > ( & ir_sig , flags ) ? ;
let ( uses , defs , clobbers ) = abisig_to _uses_defs_clobbers< M > ( & sig ) ;
let ( uses , defs , clobbers ) = sig . call _uses_defs_clobbers< M > ( ) ;
Ok ( ABICallerImpl {
ir_sig ,
sig ,
@ -1629,21 +1700,7 @@ impl<M: ABIMachineSpec> ABICaller for ABICallerImpl<M> {
}
fn get_copy_to_arg_order ( & self ) -> SmallVec < [ usize ; 8 ] > {
let mut ret = SmallVec ::new ( ) ;
for ( i , arg ) in self . sig . args . iter ( ) . enumerate ( ) {
// Struct args.
if arg . is_struct_arg ( ) {
ret . push ( i ) ;
}
}
for ( i , arg ) in self . sig . args . iter ( ) . enumerate ( ) {
// Non-struct args. Skip an appended return-area arg for multivalue
// returns, if any.
if ! arg . is_struct_arg ( ) & & i < self . ir_sig . params . len ( ) {
ret . push ( i ) ;
}
}
ret
self . sig . copy_to_arg_order . clone ( )
}
fn emit_copy_retval_to_regs < C : LowerCtx < I = Self ::I > > (
Ulrich Weigand
2 years ago
GitHub