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Add 'compiler/rustc_codegen_cranelift/' from commit '793d26047f994e23415f8f6bb5686ff25d3dda92'

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git-subtree-dir: compiler/rustc_codegen_cranelift
git-subtree-mainline: cf798c1ec6
git-subtree-split: 793d26047f
This commit is contained in:
bjorn3
2020-10-26 09:53:27 +01:00
parent cf798c1ec6 793d26047f
commit ac4f7deb2f
86 changed files with 16617 additions and 0 deletions
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201
compiler/rustc_codegen_cranelift/src/cast.rs Normal file
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//! Various number casting functions
use crate::prelude::*;
pub(crate) fn clif_intcast(
fx: &mut FunctionCx<'_, '_, impl Module>,
val: Value,
to: Type,
signed: bool,
) -> Value {
let from = fx.bcx.func.dfg.value_type(val);
match (from, to) {
// equal
(_, _) if from == to => val,
// extend
(_, types::I128) => {
let lo = if from == types::I64 {
val
} else if signed {
fx.bcx.ins().sextend(types::I64, val)
} else {
fx.bcx.ins().uextend(types::I64, val)
};
let hi = if signed {
fx.bcx.ins().sshr_imm(lo, 63)
} else {
fx.bcx.ins().iconst(types::I64, 0)
};
fx.bcx.ins().iconcat(lo, hi)
}
(_, _) if to.wider_or_equal(from) => {
if signed {
fx.bcx.ins().sextend(to, val)
} else {
fx.bcx.ins().uextend(to, val)
}
}
// reduce
(types::I128, _) => {
let (lsb, _msb) = fx.bcx.ins().isplit(val);
if to == types::I64 {
lsb
} else {
fx.bcx.ins().ireduce(to, lsb)
}
}
(_, _) => fx.bcx.ins().ireduce(to, val),
}
}
pub(crate) fn clif_int_or_float_cast(
fx: &mut FunctionCx<'_, '_, impl Module>,
from: Value,
from_signed: bool,
to_ty: Type,
to_signed: bool,
) -> Value {
let from_ty = fx.bcx.func.dfg.value_type(from);
if from_ty.is_int() && to_ty.is_int() {
// int-like -> int-like
clif_intcast(
fx,
from,
to_ty,
// This is correct as either from_signed == to_signed (=> this is trivially correct)
// Or from_clif_ty == to_clif_ty, which means this is a no-op.
from_signed,
)
} else if from_ty.is_int() && to_ty.is_float() {
if from_ty == types::I128 {
// _______ss__f_
// __float tisf: i128 -> f32
// __float tidf: i128 -> f64
// __floatuntisf: u128 -> f32
// __floatuntidf: u128 -> f64
let name = format!(
"__float{sign}ti{flt}f",
sign = if from_signed { "" } else { "un" },
flt = match to_ty {
types::F32 => "s",
types::F64 => "d",
_ => unreachable!("{:?}", to_ty),
},
);
let from_rust_ty = if from_signed {
fx.tcx.types.i128
} else {
fx.tcx.types.u128
};
let to_rust_ty = match to_ty {
types::F32 => fx.tcx.types.f32,
types::F64 => fx.tcx.types.f64,
_ => unreachable!(),
};
return fx
.easy_call(
&name,
&[CValue::by_val(from, fx.layout_of(from_rust_ty))],
to_rust_ty,
)
.load_scalar(fx);
}
// int-like -> float
if from_signed {
fx.bcx.ins().fcvt_from_sint(to_ty, from)
} else {
fx.bcx.ins().fcvt_from_uint(to_ty, from)
}
} else if from_ty.is_float() && to_ty.is_int() {
if to_ty == types::I128 {
// _____sssf___
// __fix sfti: f32 -> i128
// __fix dfti: f64 -> i128
// __fixunssfti: f32 -> u128
// __fixunsdfti: f64 -> u128
let name = format!(
"__fix{sign}{flt}fti",
sign = if to_signed { "" } else { "uns" },
flt = match from_ty {
types::F32 => "s",
types::F64 => "d",
_ => unreachable!("{:?}", to_ty),
},
);
let from_rust_ty = match from_ty {
types::F32 => fx.tcx.types.f32,
types::F64 => fx.tcx.types.f64,
_ => unreachable!(),
};
let to_rust_ty = if to_signed {
fx.tcx.types.i128
} else {
fx.tcx.types.u128
};
return fx
.easy_call(
&name,
&[CValue::by_val(from, fx.layout_of(from_rust_ty))],
to_rust_ty,
)
.load_scalar(fx);
}
// float -> int-like
if to_ty == types::I8 || to_ty == types::I16 {
// FIXME implement fcvt_to_*int_sat.i8/i16
let val = if to_signed {
fx.bcx.ins().fcvt_to_sint_sat(types::I32, from)
} else {
fx.bcx.ins().fcvt_to_uint_sat(types::I32, from)
};
let (min, max) = match (to_ty, to_signed) {
(types::I8, false) => (0, i64::from(u8::MAX)),
(types::I16, false) => (0, i64::from(u16::MAX)),
(types::I8, true) => (i64::from(i8::MIN), i64::from(i8::MAX)),
(types::I16, true) => (i64::from(i16::MIN), i64::from(i16::MAX)),
_ => unreachable!(),
};
let min_val = fx.bcx.ins().iconst(types::I32, min);
let max_val = fx.bcx.ins().iconst(types::I32, max);
let val = if to_signed {
let has_underflow = fx.bcx.ins().icmp_imm(IntCC::SignedLessThan, val, min);
let has_overflow = fx.bcx.ins().icmp_imm(IntCC::SignedGreaterThan, val, max);
let bottom_capped = fx.bcx.ins().select(has_underflow, min_val, val);
fx.bcx.ins().select(has_overflow, max_val, bottom_capped)
} else {
let has_overflow = fx.bcx.ins().icmp_imm(IntCC::UnsignedGreaterThan, val, max);
fx.bcx.ins().select(has_overflow, max_val, val)
};
fx.bcx.ins().ireduce(to_ty, val)
} else {
if to_signed {
fx.bcx.ins().fcvt_to_sint_sat(to_ty, from)
} else {
fx.bcx.ins().fcvt_to_uint_sat(to_ty, from)
}
}
} else if from_ty.is_float() && to_ty.is_float() {
// float -> float
match (from_ty, to_ty) {
(types::F32, types::F64) => fx.bcx.ins().fpromote(types::F64, from),
(types::F64, types::F32) => fx.bcx.ins().fdemote(types::F32, from),
_ => from,
}
} else {
unreachable!("cast value from {:?} to {:?}", from_ty, to_ty);
}
}