Auto merge of #3159 - eduardosm:sse41-round, r=RalfJung

Implement round.ps and round.pd SSE4.1 intrinsics

I had forgotten them.

I also increased the coverage of rounding tests to make sure the rounding direction is working as expected (e.g. test `1.25`, `1.5`, `1.75`...).
This commit is contained in:
bors 2023-11-12 18:24:42 +00:00
commit f86fa09ec6
2 changed files with 388 additions and 112 deletions

View File

@ -148,6 +148,14 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
round_first::<rustc_apfloat::ieee::Single>(this, left, right, rounding, dest)?;
}
// Used to implement the _mm_floor_ps, _mm_ceil_ps and _mm_round_ps
// functions. Rounds the elements of `op` according to `rounding`.
"round.ps" => {
let [op, rounding] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
round_all::<rustc_apfloat::ieee::Single>(this, op, rounding, dest)?;
}
// Used to implement the _mm_floor_sd, _mm_ceil_sd and _mm_round_sd
// functions. Rounds the first element of `right` according to `rounding`
// and copies the remaining elements from `left`.
@ -157,6 +165,14 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
round_first::<rustc_apfloat::ieee::Double>(this, left, right, rounding, dest)?;
}
// Used to implement the _mm_floor_pd, _mm_ceil_pd and _mm_round_pd
// functions. Rounds the elements of `op` according to `rounding`.
"round.pd" => {
let [op, rounding] =
this.check_shim(abi, Abi::C { unwind: false }, link_name, args)?;
round_all::<rustc_apfloat::ieee::Double>(this, op, rounding, dest)?;
}
// Used to implement the _mm_minpos_epu16 function.
// Find the minimum unsinged 16-bit integer in `op` and
// returns its value and position.
@ -283,22 +299,7 @@ fn round_first<'tcx, F: rustc_apfloat::Float>(
assert_eq!(dest_len, left_len);
assert_eq!(dest_len, right_len);
// The fourth bit of `rounding` only affects the SSE status
// register, which cannot be accessed from Miri (or from Rust,
// for that matter), so we can ignore it.
let rounding = match this.read_scalar(rounding)?.to_i32()? & !0b1000 {
// When the third bit is 0, the rounding mode is determined by the
// first two bits.
0b000 => rustc_apfloat::Round::NearestTiesToEven,
0b001 => rustc_apfloat::Round::TowardNegative,
0b010 => rustc_apfloat::Round::TowardPositive,
0b011 => rustc_apfloat::Round::TowardZero,
// When the third bit is 1, the rounding mode is determined by the
// SSE status register. Since we do not support modifying it from
// Miri (or Rust), we assume it to be at its default mode (round-to-nearest).
0b100..=0b111 => rustc_apfloat::Round::NearestTiesToEven,
rounding => throw_unsup_format!("unsupported rounding mode 0x{rounding:02x}"),
};
let rounding = rounding_from_imm(this.read_scalar(rounding)?.to_i32()?)?;
let op0: F = this.read_scalar(&this.project_index(&right, 0)?)?.to_float()?;
let res = op0.round_to_integral(rounding).value;
@ -317,3 +318,50 @@ fn round_first<'tcx, F: rustc_apfloat::Float>(
Ok(())
}
// Rounds all elements of `op` according to `rounding`.
fn round_all<'tcx, F: rustc_apfloat::Float>(
this: &mut crate::MiriInterpCx<'_, 'tcx>,
op: &OpTy<'tcx, Provenance>,
rounding: &OpTy<'tcx, Provenance>,
dest: &PlaceTy<'tcx, Provenance>,
) -> InterpResult<'tcx, ()> {
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 rounding = rounding_from_imm(this.read_scalar(rounding)?.to_i32()?)?;
for i in 0..dest_len {
let op: F = this.read_scalar(&this.project_index(&op, i)?)?.to_float()?;
let res = op.round_to_integral(rounding).value;
this.write_scalar(
Scalar::from_uint(res.to_bits(), Size::from_bits(F::BITS)),
&this.project_index(&dest, i)?,
)?;
}
Ok(())
}
/// Gets equivalent `rustc_apfloat::Round` from rounding mode immediate of
/// `round.{ss,sd,ps,pd}` intrinsics.
fn rounding_from_imm<'tcx>(rounding: i32) -> InterpResult<'tcx, rustc_apfloat::Round> {
// The fourth bit of `rounding` only affects the SSE status
// register, which cannot be accessed from Miri (or from Rust,
// for that matter), so we can ignore it.
match rounding & !0b1000 {
// When the third bit is 0, the rounding mode is determined by the
// first two bits.
0b000 => Ok(rustc_apfloat::Round::NearestTiesToEven),
0b001 => Ok(rustc_apfloat::Round::TowardNegative),
0b010 => Ok(rustc_apfloat::Round::TowardPositive),
0b011 => Ok(rustc_apfloat::Round::TowardZero),
// When the third bit is 1, the rounding mode is determined by the
// SSE status register. Since we do not support modifying it from
// Miri (or Rust), we assume it to be at its default mode (round-to-nearest).
0b100..=0b111 => Ok(rustc_apfloat::Round::NearestTiesToEven),
rounding => throw_unsup_format!("unsupported rounding mode 0x{rounding:02x}"),
}
}

View File

@ -73,114 +73,342 @@ unsafe fn test_sse41() {
test_mm_dp_ps();
#[target_feature(enable = "sse4.1")]
unsafe fn test_mm_floor_sd() {
let a = _mm_setr_pd(2.5, 4.5);
let b = _mm_setr_pd(-1.5, -3.5);
let r = _mm_floor_sd(a, b);
let e = _mm_setr_pd(-2.0, 4.5);
assert_eq_m128d(r, e);
}
test_mm_floor_sd();
unsafe fn test_round_nearest_f32() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f32, res: f32) {
let a = _mm_setr_ps(3.5, 2.5, 1.5, 4.5);
let b = _mm_setr_ps(x, -1.5, -3.5, -2.5);
let e = _mm_setr_ps(res, 2.5, 1.5, 4.5);
let r = _mm_round_ss::<_MM_FROUND_TO_NEAREST_INT>(a, b);
assert_eq_m128(r, e);
// Assume round-to-nearest by default
let r = _mm_round_ss::<_MM_FROUND_CUR_DIRECTION>(a, b);
assert_eq_m128(r, e);
#[target_feature(enable = "sse4.1")]
unsafe fn test_mm_floor_ss() {
let a = _mm_setr_ps(2.5, 4.5, 8.5, 16.5);
let b = _mm_setr_ps(-1.5, -3.5, -7.5, -15.5);
let r = _mm_floor_ss(a, b);
let e = _mm_setr_ps(-2.0, 4.5, 8.5, 16.5);
let a = _mm_set1_ps(x);
let e = _mm_set1_ps(res);
let r = _mm_round_ps::<_MM_FROUND_TO_NEAREST_INT>(a);
assert_eq_m128(r, e);
// Assume round-to-nearest by default
let r = _mm_round_ps::<_MM_FROUND_CUR_DIRECTION>(a);
assert_eq_m128(r, e);
}
// Test rounding direction
test(-2.5, -2.0);
test(-1.75, -2.0);
test(-1.5, -2.0);
test(-1.25, -1.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 1.0);
test(1.5, 2.0);
test(1.75, 2.0);
test(2.5, 2.0);
// Test that each element is rounded
let a = _mm_setr_ps(1.5, 3.5, 5.5, 7.5);
let e = _mm_setr_ps(2.0, 4.0, 6.0, 8.0);
let r = _mm_round_ps::<_MM_FROUND_TO_NEAREST_INT>(a);
assert_eq_m128(r, e);
}
test_mm_floor_ss();
#[target_feature(enable = "sse4.1")]
unsafe fn test_mm_ceil_sd() {
let a = _mm_setr_pd(1.5, 3.5);
let b = _mm_setr_pd(-2.5, -4.5);
let r = _mm_ceil_sd(a, b);
let e = _mm_setr_pd(-2.0, 3.5);
assert_eq_m128d(r, e);
}
test_mm_ceil_sd();
#[target_feature(enable = "sse4.1")]
unsafe fn test_mm_ceil_ss() {
let a = _mm_setr_ps(1.5, 3.5, 7.5, 15.5);
let b = _mm_setr_ps(-2.5, -4.5, -8.5, -16.5);
let r = _mm_ceil_ss(a, b);
let e = _mm_setr_ps(-2.0, 3.5, 7.5, 15.5);
assert_eq_m128(r, e);
}
test_mm_ceil_ss();
#[target_feature(enable = "sse4.1")]
unsafe fn test_mm_round_sd() {
let a = _mm_setr_pd(1.5, 3.5);
let b = _mm_setr_pd(-2.5, -4.5);
let r = _mm_round_sd::<_MM_FROUND_TO_NEAREST_INT>(a, b);
let e = _mm_setr_pd(-2.0, 3.5);
assert_eq_m128d(r, e);
let a = _mm_setr_pd(1.5, 3.5);
let b = _mm_setr_pd(-2.5, -4.5);
let r = _mm_round_sd::<_MM_FROUND_TO_NEG_INF>(a, b);
let e = _mm_setr_pd(-3.0, 3.5);
assert_eq_m128d(r, e);
let a = _mm_setr_pd(1.5, 3.5);
let b = _mm_setr_pd(-2.5, -4.5);
let r = _mm_round_sd::<_MM_FROUND_TO_POS_INF>(a, b);
let e = _mm_setr_pd(-2.0, 3.5);
assert_eq_m128d(r, e);
let a = _mm_setr_pd(1.5, 3.5);
let b = _mm_setr_pd(-2.5, -4.5);
let r = _mm_round_sd::<_MM_FROUND_TO_ZERO>(a, b);
let e = _mm_setr_pd(-2.0, 3.5);
assert_eq_m128d(r, e);
// Assume round-to-nearest by default
let a = _mm_setr_pd(1.5, 3.5);
let b = _mm_setr_pd(-2.5, -4.5);
let r = _mm_round_sd::<_MM_FROUND_CUR_DIRECTION>(a, b);
let e = _mm_setr_pd(-2.0, 3.5);
assert_eq_m128d(r, e);
let r = _mm_round_ps::<_MM_FROUND_CUR_DIRECTION>(a);
assert_eq_m128(r, e);
}
test_mm_round_sd();
test_round_nearest_f32();
#[target_feature(enable = "sse4.1")]
unsafe fn test_mm_round_ss() {
let a = _mm_setr_ps(1.5, 3.5, 7.5, 15.5);
let b = _mm_setr_ps(-1.75, -4.5, -8.5, -16.5);
let r = _mm_round_ss::<_MM_FROUND_TO_NEAREST_INT>(a, b);
let e = _mm_setr_ps(-2.0, 3.5, 7.5, 15.5);
assert_eq_m128(r, e);
unsafe fn test_round_floor_f32() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f32, res: f32) {
let a = _mm_setr_ps(3.5, 2.5, 1.5, 4.5);
let b = _mm_setr_ps(x, -1.5, -3.5, -2.5);
let e = _mm_setr_ps(res, 2.5, 1.5, 4.5);
let r = _mm_floor_ss(a, b);
assert_eq_m128(r, e);
let r = _mm_round_ss::<_MM_FROUND_TO_NEG_INF>(a, b);
assert_eq_m128(r, e);
let a = _mm_setr_ps(1.5, 3.5, 7.5, 15.5);
let b = _mm_setr_ps(-1.75, -4.5, -8.5, -16.5);
let r = _mm_round_ss::<_MM_FROUND_TO_NEG_INF>(a, b);
let e = _mm_setr_ps(-2.0, 3.5, 7.5, 15.5);
assert_eq_m128(r, e);
let a = _mm_set1_ps(x);
let e = _mm_set1_ps(res);
let r = _mm_floor_ps(a);
assert_eq_m128(r, e);
let r = _mm_round_ps::<_MM_FROUND_TO_NEG_INF>(a);
assert_eq_m128(r, e);
}
let a = _mm_setr_ps(1.5, 3.5, 7.5, 15.5);
let b = _mm_setr_ps(-1.75, -4.5, -8.5, -16.5);
let r = _mm_round_ss::<_MM_FROUND_TO_POS_INF>(a, b);
let e = _mm_setr_ps(-1.0, 3.5, 7.5, 15.5);
assert_eq_m128(r, e);
// Test rounding direction
test(-2.5, -3.0);
test(-1.75, -2.0);
test(-1.5, -2.0);
test(-1.25, -2.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 1.0);
test(1.5, 1.0);
test(1.75, 1.0);
test(2.5, 2.0);
let a = _mm_setr_ps(1.5, 3.5, 7.5, 15.5);
let b = _mm_setr_ps(-1.75, -4.5, -8.5, -16.5);
let r = _mm_round_ss::<_MM_FROUND_TO_ZERO>(a, b);
let e = _mm_setr_ps(-1.0, 3.5, 7.5, 15.5);
// Test that each element is rounded
let a = _mm_setr_ps(1.5, 3.5, 5.5, 7.5);
let e = _mm_setr_ps(1.0, 3.0, 5.0, 7.0);
let r = _mm_floor_ps(a);
assert_eq_m128(r, e);
// Assume round-to-nearest by default
let a = _mm_setr_ps(1.5, 3.5, 7.5, 15.5);
let b = _mm_setr_ps(-1.75, -4.5, -8.5, -16.5);
let r = _mm_round_ss::<_MM_FROUND_CUR_DIRECTION>(a, b);
let e = _mm_setr_ps(-2.0, 3.5, 7.5, 15.5);
let r = _mm_round_ps::<_MM_FROUND_TO_NEG_INF>(a);
assert_eq_m128(r, e);
}
test_mm_round_ss();
test_round_floor_f32();
#[target_feature(enable = "sse4.1")]
unsafe fn test_round_ceil_f32() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f32, res: f32) {
let a = _mm_setr_ps(3.5, 2.5, 1.5, 4.5);
let b = _mm_setr_ps(x, -1.5, -3.5, -2.5);
let e = _mm_setr_ps(res, 2.5, 1.5, 4.5);
let r = _mm_ceil_ss(a, b);
assert_eq_m128(r, e);
let r = _mm_round_ss::<_MM_FROUND_TO_POS_INF>(a, b);
assert_eq_m128(r, e);
let a = _mm_set1_ps(x);
let e = _mm_set1_ps(res);
let r = _mm_ceil_ps(a);
assert_eq_m128(r, e);
let r = _mm_round_ps::<_MM_FROUND_TO_POS_INF>(a);
assert_eq_m128(r, e);
}
// Test rounding direction
test(-2.5, -2.0);
test(-1.75, -1.0);
test(-1.5, -1.0);
test(-1.25, -1.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 2.0);
test(1.5, 2.0);
test(1.75, 2.0);
test(2.5, 3.0);
// Test that each element is rounded
let a = _mm_setr_ps(1.5, 3.5, 5.5, 7.5);
let e = _mm_setr_ps(2.0, 4.0, 6.0, 8.0);
let r = _mm_ceil_ps(a);
assert_eq_m128(r, e);
let r = _mm_round_ps::<_MM_FROUND_TO_POS_INF>(a);
assert_eq_m128(r, e);
}
test_round_ceil_f32();
#[target_feature(enable = "sse4.1")]
unsafe fn test_round_trunc_f32() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f32, res: f32) {
let a = _mm_setr_ps(3.5, 2.5, 1.5, 4.5);
let b = _mm_setr_ps(x, -1.5, -3.5, -2.5);
let e = _mm_setr_ps(res, 2.5, 1.5, 4.5);
let r = _mm_round_ss::<_MM_FROUND_TO_ZERO>(a, b);
assert_eq_m128(r, e);
let a = _mm_set1_ps(x);
let e = _mm_set1_ps(res);
let r = _mm_round_ps::<_MM_FROUND_TO_ZERO>(a);
assert_eq_m128(r, e);
}
// Test rounding direction
test(-2.5, -2.0);
test(-1.75, -1.0);
test(-1.5, -1.0);
test(-1.25, -1.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 1.0);
test(1.5, 1.0);
test(1.75, 1.0);
test(2.5, 2.0);
// Test that each element is rounded
let a = _mm_setr_ps(1.5, 3.5, 5.5, 7.5);
let e = _mm_setr_ps(1.0, 3.0, 5.0, 7.0);
let r = _mm_round_ps::<_MM_FROUND_TO_ZERO>(a);
assert_eq_m128(r, e);
}
test_round_trunc_f32();
#[target_feature(enable = "sse4.1")]
unsafe fn test_round_nearest_f64() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f64, res: f64) {
let a = _mm_setr_pd(3.5, 2.5);
let b = _mm_setr_pd(x, -1.5);
let e = _mm_setr_pd(res, 2.5);
let r = _mm_round_sd::<_MM_FROUND_TO_NEAREST_INT>(a, b);
assert_eq_m128d(r, e);
// Assume round-to-nearest by default
let r = _mm_round_sd::<_MM_FROUND_CUR_DIRECTION>(a, b);
assert_eq_m128d(r, e);
let a = _mm_set1_pd(x);
let e = _mm_set1_pd(res);
let r = _mm_round_pd::<_MM_FROUND_TO_NEAREST_INT>(a);
assert_eq_m128d(r, e);
// Assume round-to-nearest by default
let r = _mm_round_pd::<_MM_FROUND_CUR_DIRECTION>(a);
assert_eq_m128d(r, e);
}
// Test rounding direction
test(-2.5, -2.0);
test(-1.75, -2.0);
test(-1.5, -2.0);
test(-1.25, -1.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 1.0);
test(1.5, 2.0);
test(1.75, 2.0);
test(2.5, 2.0);
// Test that each element is rounded
let a = _mm_setr_pd(1.5, 3.5);
let e = _mm_setr_pd(2.0, 4.0);
let r = _mm_round_pd::<_MM_FROUND_TO_NEAREST_INT>(a);
assert_eq_m128d(r, e);
// Assume round-to-nearest by default
let r = _mm_round_pd::<_MM_FROUND_CUR_DIRECTION>(a);
assert_eq_m128d(r, e);
}
test_round_nearest_f64();
#[target_feature(enable = "sse4.1")]
unsafe fn test_round_floor_f64() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f64, res: f64) {
let a = _mm_setr_pd(3.5, 2.5);
let b = _mm_setr_pd(x, -1.5);
let e = _mm_setr_pd(res, 2.5);
let r = _mm_floor_sd(a, b);
assert_eq_m128d(r, e);
let r = _mm_round_sd::<_MM_FROUND_TO_NEG_INF>(a, b);
assert_eq_m128d(r, e);
let a = _mm_set1_pd(x);
let e = _mm_set1_pd(res);
let r = _mm_floor_pd(a);
assert_eq_m128d(r, e);
let r = _mm_round_pd::<_MM_FROUND_TO_NEG_INF>(a);
assert_eq_m128d(r, e);
}
// Test rounding direction
test(-2.5, -3.0);
test(-1.75, -2.0);
test(-1.5, -2.0);
test(-1.25, -2.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 1.0);
test(1.5, 1.0);
test(1.75, 1.0);
test(2.5, 2.0);
// Test that each element is rounded
let a = _mm_setr_pd(1.5, 3.5);
let e = _mm_setr_pd(1.0, 3.0);
let r = _mm_floor_pd(a);
assert_eq_m128d(r, e);
let r = _mm_round_pd::<_MM_FROUND_TO_NEG_INF>(a);
assert_eq_m128d(r, e);
}
test_round_floor_f64();
#[target_feature(enable = "sse4.1")]
unsafe fn test_round_ceil_f64() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f64, res: f64) {
let a = _mm_setr_pd(3.5, 2.5);
let b = _mm_setr_pd(x, -1.5);
let e = _mm_setr_pd(res, 2.5);
let r = _mm_ceil_sd(a, b);
assert_eq_m128d(r, e);
let r = _mm_round_sd::<_MM_FROUND_TO_POS_INF>(a, b);
assert_eq_m128d(r, e);
let a = _mm_set1_pd(x);
let e = _mm_set1_pd(res);
let r = _mm_ceil_pd(a);
assert_eq_m128d(r, e);
let r = _mm_round_pd::<_MM_FROUND_TO_POS_INF>(a);
assert_eq_m128d(r, e);
}
// Test rounding direction
test(-2.5, -2.0);
test(-1.75, -1.0);
test(-1.5, -1.0);
test(-1.25, -1.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 2.0);
test(1.5, 2.0);
test(1.75, 2.0);
test(2.5, 3.0);
// Test that each element is rounded
let a = _mm_setr_pd(1.5, 3.5);
let e = _mm_setr_pd(2.0, 4.0);
let r = _mm_ceil_pd(a);
assert_eq_m128d(r, e);
let r = _mm_round_pd::<_MM_FROUND_TO_POS_INF>(a);
assert_eq_m128d(r, e);
}
test_round_ceil_f64();
#[target_feature(enable = "sse4.1")]
unsafe fn test_round_trunc_f64() {
#[target_feature(enable = "sse4.1")]
unsafe fn test(x: f64, res: f64) {
let a = _mm_setr_pd(3.5, 2.5);
let b = _mm_setr_pd(x, -1.5);
let e = _mm_setr_pd(res, 2.5);
let r = _mm_round_sd::<_MM_FROUND_TO_ZERO>(a, b);
assert_eq_m128d(r, e);
let a = _mm_set1_pd(x);
let e = _mm_set1_pd(res);
let r = _mm_round_pd::<_MM_FROUND_TO_ZERO>(a);
assert_eq_m128d(r, e);
}
// Test rounding direction
test(-2.5, -2.0);
test(-1.75, -1.0);
test(-1.5, -1.0);
test(-1.25, -1.0);
test(-1.0, -1.0);
test(0.0, 0.0);
test(1.0, 1.0);
test(1.25, 1.0);
test(1.5, 1.0);
test(1.75, 1.0);
test(2.5, 2.0);
// Test that each element is rounded
let a = _mm_setr_pd(1.5, 3.5);
let e = _mm_setr_pd(1.0, 3.0);
let r = _mm_round_pd::<_MM_FROUND_TO_ZERO>(a);
assert_eq_m128d(r, e);
}
test_round_trunc_f64();
#[target_feature(enable = "sse4.1")]
unsafe fn test_mm_minpos_epu16() {