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use rustc_apfloat::{
ieee::{Double, Single},
Float as _,
};
use rustc_middle::mir;
use rustc_middle::ty::layout::LayoutOf as _;
use rustc_middle::ty::Ty;
use rustc_span::Symbol;
use rustc_target::spec::abi::Abi;
use super::{bin_op_simd_float_all, bin_op_simd_float_first, FloatBinOp, FloatCmpOp};
use crate::*;
use shims::foreign_items::EmulateByNameResult;
impl<'mir, 'tcx: 'mir> EvalContextExt<'mir, 'tcx> for crate::MiriInterpCx<'mir, 'tcx> {}
pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
crate::MiriInterpCxExt<'mir, 'tcx>
{
fn emulate_x86_sse2_intrinsic(
&mut self,
link_name: Symbol,
abi: Abi,
args: &[OpTy<'tcx, Provenance>],
dest: &PlaceTy<'tcx, Provenance>,
) -> InterpResult<'tcx, EmulateByNameResult<'mir, 'tcx>> {
let this = self.eval_context_mut();
// Prefix should have already been checked.
let unprefixed_name = link_name.as_str().strip_prefix("llvm.x86.sse2.").unwrap();
// These intrinsics operate on 128-bit (f32x4, f64x2, i8x16, i16x8, i32x4, i64x2) SIMD
// vectors unless stated otherwise.
// Many intrinsic names are sufixed with "ps" (packed single), "ss" (scalar signle),
// "pd" (packed double) or "sd" (scalar double), where single means single precision
// floating point (f32) and double means double precision floating point (f64). "ps"
// and "pd" means thet the operation is performed on each element of the vector, while
// "ss" and "sd" means that the operation is performed only on the first element, copying
// the remaining elements from the input vector (for binary operations, from the left-hand
// side).
// Intrinsincs sufixed with "epiX" or "epuX" operate with X-bit signed or unsigned
// vectors.
match unprefixed_name {
// Used to implement the _mm_avg_epu8 and _mm_avg_epu16 functions.
// Averages packed unsigned 8/16-bit integers in `left` and `right`.
"pavg.b" | "pavg.w" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, left_len);
assert_eq!(dest_len, right_len);
for i in 0..dest_len {
let left = this.read_immediate(&this.project_index(&left, i)?)?;
let right = this.read_immediate(&this.project_index(&right, i)?)?;
let dest = this.project_index(&dest, i)?;
// Widen the operands to avoid overflow
let twice_wide = this.layout_of(this.get_twice_wide_int_ty(left.layout.ty))?;
let left = this.int_to_int_or_float(&left, twice_wide)?;
let right = this.int_to_int_or_float(&right, twice_wide)?;
// Calculate left + right + 1
let added = this.wrapping_binary_op(mir::BinOp::Add, &left, &right)?;
let added = this.wrapping_binary_op(
mir::BinOp::Add,
&added,
&ImmTy::from_uint(1u32, twice_wide),
)?;
// Calculate (left + right + 1) / 2
let divided = this.wrapping_binary_op(
mir::BinOp::Div,
&added,
&ImmTy::from_uint(2u32, twice_wide),
)?;
// Narrow back to the original type
let res = this.int_to_int_or_float(÷d, dest.layout)?;
this.write_immediate(*res, &dest)?;
}
}
// Used to implement the _mm_madd_epi16 function.
// Multiplies packed signed 16-bit integers in `left` and `right`, producing
// intermediate signed 32-bit integers. Horizontally add adjacent pairs of
// intermediate 32-bit integers, and pack the results in `dest`.
"pmadd.wd" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(left_len, right_len);
assert_eq!(dest_len.checked_mul(2).unwrap(), left_len);
for i in 0..dest_len {
let j1 = i.checked_mul(2).unwrap();
let left1 = this.read_scalar(&this.project_index(&left, j1)?)?.to_i16()?;
let right1 = this.read_scalar(&this.project_index(&right, j1)?)?.to_i16()?;
let j2 = j1.checked_add(1).unwrap();
let left2 = this.read_scalar(&this.project_index(&left, j2)?)?.to_i16()?;
let right2 = this.read_scalar(&this.project_index(&right, j2)?)?.to_i16()?;
let dest = this.project_index(&dest, i)?;
// Multiplications are i16*i16->i32, which will not overflow.
let mul1 = i32::from(left1).checked_mul(right1.into()).unwrap();
let mul2 = i32::from(left2).checked_mul(right2.into()).unwrap();
// However, this addition can overflow in the most extreme case
// (-0x8000)*(-0x8000)+(-0x8000)*(-0x8000) = 0x80000000
let res = mul1.wrapping_add(mul2);
this.write_scalar(Scalar::from_i32(res), &dest)?;
}
}
// Used to implement the _mm_mulhi_epi16 and _mm_mulhi_epu16 functions.
"pmulh.w" | "pmulhu.w" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, left_len);
assert_eq!(dest_len, right_len);
for i in 0..dest_len {
let left = this.read_immediate(&this.project_index(&left, i)?)?;
let right = this.read_immediate(&this.project_index(&right, i)?)?;
let dest = this.project_index(&dest, i)?;
// Widen the operands to avoid overflow
let twice_wide = this.layout_of(this.get_twice_wide_int_ty(left.layout.ty))?;
let left = this.int_to_int_or_float(&left, twice_wide)?;
let right = this.int_to_int_or_float(&right, twice_wide)?;
// Multiply
let multiplied = this.wrapping_binary_op(mir::BinOp::Mul, &left, &right)?;
// Keep the high half
let high = this.wrapping_binary_op(
mir::BinOp::Shr,
&multiplied,
&ImmTy::from_uint(dest.layout.size.bits(), twice_wide),
)?;
// Narrow back to the original type
let res = this.int_to_int_or_float(&high, dest.layout)?;
this.write_immediate(*res, &dest)?;
}
}
// Used to implement the _mm_mul_epu32 function.
// Multiplies the the low unsigned 32-bit integers from each packed
// 64-bit element and stores the result as 64-bit unsigned integers.
"pmulu.dq" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
// left and right are u32x4, dest is u64x2
assert_eq!(left_len, 4);
assert_eq!(right_len, 4);
assert_eq!(dest_len, 2);
for i in 0..dest_len {
let op_i = i.checked_mul(2).unwrap();
let left = this.read_scalar(&this.project_index(&left, op_i)?)?.to_u32()?;
let right = this.read_scalar(&this.project_index(&right, op_i)?)?.to_u32()?;
let dest = this.project_index(&dest, i)?;
// The multiplication will not overflow because stripping the
// operands are expanded from 32-bit to 64-bit.
let res = u64::from(left).checked_mul(u64::from(right)).unwrap();
this.write_scalar(Scalar::from_u64(res), &dest)?;
}
}
// Used to implement the _mm_sad_epu8 function.
// Computes the absolute differences of packed unsigned 8-bit integers in `a`
// and `b`, then horizontally sum each consecutive 8 differences to produce
// two unsigned 16-bit integers, and pack these unsigned 16-bit integers in
// the low 16 bits of 64-bit elements returned.
//
// https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=_mm_sad_epu8
"psad.bw" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
// left and right are u8x16, dest is u64x2
assert_eq!(left_len, right_len);
assert_eq!(left_len, 16);
assert_eq!(dest_len, 2);
for i in 0..dest_len {
let dest = this.project_index(&dest, i)?;
let mut res: u16 = 0;
let n = left_len.checked_div(dest_len).unwrap();
for j in 0..n {
let op_i = j.checked_add(i.checked_mul(n).unwrap()).unwrap();
let left = this.read_scalar(&this.project_index(&left, op_i)?)?.to_u8()?;
let right =
this.read_scalar(&this.project_index(&right, op_i)?)?.to_u8()?;
res = res.checked_add(left.abs_diff(right).into()).unwrap();
}
this.write_scalar(Scalar::from_u64(res.into()), &dest)?;
}
}
// Used to implement the _mm_{sll,srl,sra}_epi16 functions.
// Shifts 16-bit packed integers in left by the amount in right.
// Both operands are vectors of 16-bit integers. However, right is
// interpreted as a single 64-bit integer (remaining bits are ignored).
// For logic shifts, when right is larger than 15, zero is produced.
// For arithmetic shifts, when right is larger than 15, the sign bit
// is copied to remaining bits.
"psll.w" | "psrl.w" | "psra.w" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, left_len);
assert_eq!(dest_len, right_len);
enum ShiftOp {
Sll,
Srl,
Sra,
}
let which = match unprefixed_name {
"psll.w" => ShiftOp::Sll,
"psrl.w" => ShiftOp::Srl,
"psra.w" => ShiftOp::Sra,
_ => unreachable!(),
};
// Get the 64-bit shift operand and convert it to the type expected
// by checked_{shl,shr} (u32).
// It is ok to saturate the value to u32::MAX because any value
// above 15 will produce the same result.
let shift = extract_first_u64(this, &right)?.try_into().unwrap_or(u32::MAX);
for i in 0..dest_len {
let left = this.read_scalar(&this.project_index(&left, i)?)?.to_u16()?;
let dest = this.project_index(&dest, i)?;
let res = match which {
ShiftOp::Sll => left.checked_shl(shift).unwrap_or(0),
ShiftOp::Srl => left.checked_shr(shift).unwrap_or(0),
#[allow(clippy::cast_possible_wrap, clippy::cast_sign_loss)]
ShiftOp::Sra => {
// Convert u16 to i16 to use arithmetic shift
let left = left as i16;
// Copy the sign bit to the remaining bits
left.checked_shr(shift).unwrap_or(left >> 15) as u16
}
};
this.write_scalar(Scalar::from_u16(res), &dest)?;
}
}
// Used to implement the _mm_{sll,srl,sra}_epi32 functions.
// 32-bit equivalent to the shift functions above.
"psll.d" | "psrl.d" | "psra.d" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, left_len);
assert_eq!(dest_len, right_len);
enum ShiftOp {
Sll,
Srl,
Sra,
}
let which = match unprefixed_name {
"psll.d" => ShiftOp::Sll,
"psrl.d" => ShiftOp::Srl,
"psra.d" => ShiftOp::Sra,
_ => unreachable!(),
};
// Get the 64-bit shift operand and convert it to the type expected
// by checked_{shl,shr} (u32).
// It is ok to saturate the value to u32::MAX because any value
// above 31 will produce the same result.
let shift = extract_first_u64(this, &right)?.try_into().unwrap_or(u32::MAX);
for i in 0..dest_len {
let left = this.read_scalar(&this.project_index(&left, i)?)?.to_u32()?;
let dest = this.project_index(&dest, i)?;
let res = match which {
ShiftOp::Sll => left.checked_shl(shift).unwrap_or(0),
ShiftOp::Srl => left.checked_shr(shift).unwrap_or(0),
#[allow(clippy::cast_possible_wrap, clippy::cast_sign_loss)]
ShiftOp::Sra => {
// Convert u32 to i32 to use arithmetic shift
let left = left as i32;
// Copy the sign bit to the remaining bits
left.checked_shr(shift).unwrap_or(left >> 31) as u32
}
};
this.write_scalar(Scalar::from_u32(res), &dest)?;
}
}
// Used to implement the _mm_{sll,srl}_epi64 functions.
// 64-bit equivalent to the shift functions above, except _mm_sra_epi64,
// which is not available in SSE2.
"psll.q" | "psrl.q" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, left_len);
assert_eq!(dest_len, right_len);
enum ShiftOp {
Sll,
Srl,
}
let which = match unprefixed_name {
"psll.q" => ShiftOp::Sll,
"psrl.q" => ShiftOp::Srl,
_ => unreachable!(),
};
// Get the 64-bit shift operand and convert it to the type expected
// by checked_{shl,shr} (u32).
// It is ok to saturate the value to u32::MAX because any value
// above 63 will produce the same result.
let shift = this
.read_scalar(&this.project_index(&right, 0)?)?
.to_u64()?
.try_into()
.unwrap_or(u32::MAX);
for i in 0..dest_len {
let left = this.read_scalar(&this.project_index(&left, i)?)?.to_u64()?;
let dest = this.project_index(&dest, i)?;
let res = match which {
ShiftOp::Sll => left.checked_shl(shift).unwrap_or(0),
ShiftOp::Srl => left.checked_shr(shift).unwrap_or(0),
};
this.write_scalar(Scalar::from_u64(res), &dest)?;
}
}
// Used to implement the _mm_cvtepi32_ps function.
// Converts packed i32 to packed f32.
// FIXME: Can we get rid of this intrinsic and just use simd_as?
"cvtdq2ps" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, op_len) = this.operand_to_simd(op)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, op_len);
for i in 0..dest_len {
let op = this.read_scalar(&this.project_index(&op, i)?)?.to_i32()?;
let dest = this.project_index(&dest, i)?;
let res = Scalar::from_f32(Single::from_i128(op.into()).value);
this.write_scalar(res, &dest)?;
}
}
// Used to implement the _mm_cvtps_epi32 and _mm_cvttps_epi32 functions.
// Converts packed f32 to packed i32.
"cvtps2dq" | "cvttps2dq" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, op_len) = this.operand_to_simd(op)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, op_len);
let rnd = match unprefixed_name {
// "current SSE rounding mode", assume nearest
// https://www.felixcloutier.com/x86/cvtps2dq
"cvtps2dq" => rustc_apfloat::Round::NearestTiesToEven,
// always truncate
// https://www.felixcloutier.com/x86/cvttps2dq
"cvttps2dq" => rustc_apfloat::Round::TowardZero,
_ => unreachable!(),
};
for i in 0..dest_len {
let op = this.read_scalar(&this.project_index(&op, i)?)?.to_f32()?;
let dest = this.project_index(&dest, i)?;
let res =
this.float_to_int_checked(op, dest.layout, rnd).unwrap_or_else(|| {
// Fallback to minimum acording to SSE2 semantics.
ImmTy::from_int(i32::MIN, this.machine.layouts.i32)
});
this.write_immediate(*res, &dest)?;
}
}
// Used to implement the _mm_packs_epi16 function.
// Converts two 16-bit integer vectors to a single 8-bit integer
// vector with signed saturation.
"packsswb.128" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
// left and right are i16x8, dest is i8x16
assert_eq!(left_len, 8);
assert_eq!(right_len, 8);
assert_eq!(dest_len, 16);
for i in 0..left_len {
let left = this.read_scalar(&this.project_index(&left, i)?)?.to_i16()?;
let right = this.read_scalar(&this.project_index(&right, i)?)?.to_i16()?;
let left_dest = this.project_index(&dest, i)?;
let right_dest = this.project_index(&dest, i.checked_add(left_len).unwrap())?;
let left_res =
i8::try_from(left).unwrap_or(if left < 0 { i8::MIN } else { i8::MAX });
let right_res =
i8::try_from(right).unwrap_or(if right < 0 { i8::MIN } else { i8::MAX });
this.write_scalar(Scalar::from_i8(left_res), &left_dest)?;
this.write_scalar(Scalar::from_i8(right_res), &right_dest)?;
}
}
// Used to implement the _mm_packus_epi16 function.
// Converts two 16-bit signed integer vectors to a single 8-bit
// unsigned integer vector with saturation.
"packuswb.128" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
// left and right are i16x8, dest is u8x16
assert_eq!(left_len, 8);
assert_eq!(right_len, 8);
assert_eq!(dest_len, 16);
for i in 0..left_len {
let left = this.read_scalar(&this.project_index(&left, i)?)?.to_i16()?;
let right = this.read_scalar(&this.project_index(&right, i)?)?.to_i16()?;
let left_dest = this.project_index(&dest, i)?;
let right_dest = this.project_index(&dest, i.checked_add(left_len).unwrap())?;
let left_res = u8::try_from(left).unwrap_or(if left < 0 { 0 } else { u8::MAX });
let right_res =
u8::try_from(right).unwrap_or(if right < 0 { 0 } else { u8::MAX });
this.write_scalar(Scalar::from_u8(left_res), &left_dest)?;
this.write_scalar(Scalar::from_u8(right_res), &right_dest)?;
}
}
// Used to implement the _mm_packs_epi32 function.
// Converts two 32-bit integer vectors to a single 16-bit integer
// vector with signed saturation.
"packssdw.128" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
// left and right are i32x4, dest is i16x8
assert_eq!(left_len, 4);
assert_eq!(right_len, 4);
assert_eq!(dest_len, 8);
for i in 0..left_len {
let left = this.read_scalar(&this.project_index(&left, i)?)?.to_i32()?;
let right = this.read_scalar(&this.project_index(&right, i)?)?.to_i32()?;
let left_dest = this.project_index(&dest, i)?;
let right_dest = this.project_index(&dest, i.checked_add(left_len).unwrap())?;
let left_res =
i16::try_from(left).unwrap_or(if left < 0 { i16::MIN } else { i16::MAX });
let right_res =
i16::try_from(right).unwrap_or(if right < 0 { i16::MIN } else { i16::MAX });
this.write_scalar(Scalar::from_i16(left_res), &left_dest)?;
this.write_scalar(Scalar::from_i16(right_res), &right_dest)?;
}
}
// Used to implement _mm_min_sd and _mm_max_sd functions.
// Note that the semantics are a bit different from Rust simd_min
// and simd_max intrinsics regarding handling of NaN and -0.0: Rust
// matches the IEEE min/max operations, while x86 has different
// semantics.
"min.sd" | "max.sd" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let which = match unprefixed_name {
"min.sd" => FloatBinOp::Min,
"max.sd" => FloatBinOp::Max,
_ => unreachable!(),
};
bin_op_simd_float_first::<Double>(this, which, left, right, dest)?;
}
// Used to implement _mm_min_pd and _mm_max_pd functions.
// Note that the semantics are a bit different from Rust simd_min
// and simd_max intrinsics regarding handling of NaN and -0.0: Rust
// matches the IEEE min/max operations, while x86 has different
// semantics.
"min.pd" | "max.pd" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let which = match unprefixed_name {
"min.pd" => FloatBinOp::Min,
"max.pd" => FloatBinOp::Max,
_ => unreachable!(),
};
bin_op_simd_float_all::<Double>(this, which, left, right, dest)?;
}
// Used to implement _mm_sqrt_sd functions.
// Performs the operations on the first component of `op` and
// copies the remaining components from `op`.
"sqrt.sd" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, op_len) = this.operand_to_simd(op)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, op_len);
let op0 = this.read_scalar(&this.project_index(&op, 0)?)?.to_u64()?;
// FIXME using host floats
let res0 = Scalar::from_u64(f64::from_bits(op0).sqrt().to_bits());
this.write_scalar(res0, &this.project_index(&dest, 0)?)?;
for i in 1..dest_len {
this.copy_op(
&this.project_index(&op, i)?,
&this.project_index(&dest, i)?,
/*allow_transmute*/ false,
)?;
}
}
// Used to implement _mm_sqrt_pd functions.
// Performs the operations on all components of `op`.
"sqrt.pd" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, op_len) = this.operand_to_simd(op)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, op_len);
for i in 0..dest_len {
let op = this.read_scalar(&this.project_index(&op, i)?)?.to_u64()?;
let dest = this.project_index(&dest, i)?;
// FIXME using host floats
let res = Scalar::from_u64(f64::from_bits(op).sqrt().to_bits());
this.write_scalar(res, &dest)?;
}
}
// Used to implement the _mm_cmp*_sd function.
// Performs a comparison operation on the first component of `left`
// and `right`, returning 0 if false or `u64::MAX` if true. The remaining
// components are copied from `left`.
"cmp.sd" => {
let [left, right, imm] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let which = FloatBinOp::Cmp(FloatCmpOp::from_intrinsic_imm(
this.read_scalar(imm)?.to_i8()?,
"llvm.x86.sse2.cmp.sd",
)?);
bin_op_simd_float_first::<Double>(this, which, left, right, dest)?;
}
// Used to implement the _mm_cmp*_pd functions.
// Performs a comparison operation on each component of `left`
// and `right`. For each component, returns 0 if false or `u64::MAX`
// if true.
"cmp.pd" => {
let [left, right, imm] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let which = FloatBinOp::Cmp(FloatCmpOp::from_intrinsic_imm(
this.read_scalar(imm)?.to_i8()?,
"llvm.x86.sse2.cmp.pd",
)?);
bin_op_simd_float_all::<Double>(this, which, left, right, dest)?;
}
// Used to implement _mm_{,u}comi{eq,lt,le,gt,ge,neq}_sd functions.
// Compares the first component of `left` and `right` and returns
// a scalar value (0 or 1).
"comieq.sd" | "comilt.sd" | "comile.sd" | "comigt.sd" | "comige.sd" | "comineq.sd"
| "ucomieq.sd" | "ucomilt.sd" | "ucomile.sd" | "ucomigt.sd" | "ucomige.sd"
| "ucomineq.sd" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, right_len) = this.operand_to_simd(right)?;
assert_eq!(left_len, right_len);
let left = this.read_scalar(&this.project_index(&left, 0)?)?.to_f64()?;
let right = this.read_scalar(&this.project_index(&right, 0)?)?.to_f64()?;
// The difference between the com* and *ucom variants is signaling
// of exceptions when either argument is a quiet NaN. We do not
// support accessing the SSE status register from miri (or from Rust,
// for that matter), so we treat equally both variants.
let res = match unprefixed_name {
"comieq.sd" | "ucomieq.sd" => left == right,
"comilt.sd" | "ucomilt.sd" => left < right,
"comile.sd" | "ucomile.sd" => left <= right,
"comigt.sd" | "ucomigt.sd" => left > right,
"comige.sd" | "ucomige.sd" => left >= right,
"comineq.sd" | "ucomineq.sd" => left != right,
_ => unreachable!(),
};
this.write_scalar(Scalar::from_i32(i32::from(res)), dest)?;
}
// Used to implement the _mm_cvtpd_ps and _mm_cvtps_pd functions.
// Converts packed f32/f64 to packed f64/f32.
"cvtpd2ps" | "cvtps2pd" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, op_len) = this.operand_to_simd(op)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
// For cvtpd2ps: op is f64x2, dest is f32x4
// For cvtps2pd: op is f32x4, dest is f64x2
// In either case, the two first values are converted
for i in 0..op_len.min(dest_len) {
let op = this.read_immediate(&this.project_index(&op, i)?)?;
let dest = this.project_index(&dest, i)?;
let res = this.float_to_float_or_int(&op, dest.layout)?;
this.write_immediate(*res, &dest)?;
}
// For f32 -> f64, ignore the remaining
// For f64 -> f32, fill the remaining with zeros
for i in op_len..dest_len {
let dest = this.project_index(&dest, i)?;
this.write_scalar(Scalar::from_int(0, dest.layout.size), &dest)?;
}
}
// Used to implement the _mm_cvtpd_epi32 and _mm_cvttpd_epi32 functions.
// Converts packed f64 to packed i32.
"cvtpd2dq" | "cvttpd2dq" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, op_len) = this.operand_to_simd(op)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
// op is f64x2, dest is i32x4
assert_eq!(op_len, 2);
assert_eq!(dest_len, 4);
let rnd = match unprefixed_name {
// "current SSE rounding mode", assume nearest
// https://www.felixcloutier.com/x86/cvtpd2dq
"cvtpd2dq" => rustc_apfloat::Round::NearestTiesToEven,
// always truncate
// https://www.felixcloutier.com/x86/cvttpd2dq
"cvttpd2dq" => rustc_apfloat::Round::TowardZero,
_ => unreachable!(),
};
for i in 0..op_len {
let op = this.read_scalar(&this.project_index(&op, i)?)?.to_f64()?;
let dest = this.project_index(&dest, i)?;
let res =
this.float_to_int_checked(op, dest.layout, rnd).unwrap_or_else(|| {
// Fallback to minimum acording to SSE2 semantics.
ImmTy::from_int(i32::MIN, this.machine.layouts.i32)
});
this.write_immediate(*res, &dest)?;
}
// Fill the remaining with zeros
for i in op_len..dest_len {
let dest = this.project_index(&dest, i)?;
this.write_scalar(Scalar::from_i32(0), &dest)?;
}
}
// Use to implement the _mm_cvtsd_si32, _mm_cvttsd_si32,
// _mm_cvtsd_si64 and _mm_cvttsd_si64 functions.
// Converts the first component of `op` from f64 to i32/i64.
"cvtsd2si" | "cvttsd2si" | "cvtsd2si64" | "cvttsd2si64" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, _) = this.operand_to_simd(op)?;
let op = this.read_scalar(&this.project_index(&op, 0)?)?.to_f64()?;
let rnd = match unprefixed_name {
// "current SSE rounding mode", assume nearest
// https://www.felixcloutier.com/x86/cvtsd2si
"cvtsd2si" | "cvtsd2si64" => rustc_apfloat::Round::NearestTiesToEven,
// always truncate
// https://www.felixcloutier.com/x86/cvttsd2si
"cvttsd2si" | "cvttsd2si64" => rustc_apfloat::Round::TowardZero,
_ => unreachable!(),
};
let res = this.float_to_int_checked(op, dest.layout, rnd).unwrap_or_else(|| {
// Fallback to minimum acording to SSE semantics.
ImmTy::from_int(dest.layout.size.signed_int_min(), dest.layout)
});
this.write_immediate(*res, dest)?;
}
// Used to implement the _mm_cvtsd_ss and _mm_cvtss_sd functions.
// Converts the first f64/f32 from `right` to f32/f64 and copies
// the remaining elements from `left`
"cvtsd2ss" | "cvtss2sd" => {
let [left, right] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (left, left_len) = this.operand_to_simd(left)?;
let (right, _) = this.operand_to_simd(right)?;
let (dest, dest_len) = this.place_to_simd(dest)?;
assert_eq!(dest_len, left_len);
// Convert first element of `right`
let right0 = this.read_immediate(&this.project_index(&right, 0)?)?;
let dest0 = this.project_index(&dest, 0)?;
// `float_to_float_or_int` here will convert from f64 to f32 (cvtsd2ss) or
// from f32 to f64 (cvtss2sd).
let res0 = this.float_to_float_or_int(&right0, dest0.layout)?;
this.write_immediate(*res0, &dest0)?;
// Copy remianing from `left`
for i in 1..dest_len {
this.copy_op(
&this.project_index(&left, i)?,
&this.project_index(&dest, i)?,
/*allow_transmute*/ false,
)?;
}
}
// Used to implement the _mm_movemask_pd function.
// Returns a scalar integer where the i-th bit is the highest
// bit of the i-th component of `op`.
// https://www.felixcloutier.com/x86/movmskpd
"movmsk.pd" => {
let [op] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
let (op, op_len) = this.operand_to_simd(op)?;
let mut res = 0;
for i in 0..op_len {
let op = this.read_scalar(&this.project_index(&op, i)?)?;
let op = op.to_u64()?;
// Extract the highest bit of `op` and place it in the `i`-th bit of `res`
res |= (op >> 63) << i;
}
this.write_scalar(Scalar::from_u32(res.try_into().unwrap()), dest)?;
}
// Used to implement the `_mm_pause` function.
// The intrinsic is used to hint the processor that the code is in a spin-loop.
"pause" => {
let [] = this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
this.yield_active_thread();
}
_ => return Ok(EmulateByNameResult::NotSupported),
}
Ok(EmulateByNameResult::NeedsJumping)
}
}
/// Takes a 128-bit vector, transmutes it to `[u64; 2]` and extracts
/// the first value.
fn extract_first_u64<'tcx>(
this: &crate::MiriInterpCx<'_, 'tcx>,
op: &MPlaceTy<'tcx, Provenance>,
) -> InterpResult<'tcx, u64> {
// Transmute vector to `[u64; 2]`
let u64_array_layout = this.layout_of(Ty::new_array(this.tcx.tcx, this.tcx.types.u64, 2))?;
let op = op.transmute(u64_array_layout, this)?;
// Get the first u64 from the array
this.read_scalar(&this.project_index(&op, 0)?)?.to_u64()
}