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Remove from miri LLVM intrinsics that are no longer needed
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@eduardosm
eduardosm committed Oct 12, 2023
1 parent b57a157 commit 337af7c
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Showing 3 changed files with 1 addition and 220 deletions.
19 changes: 0 additions & 19 deletions src/tools/miri/src/shims/x86/sse.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -209,25 +209,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
)?;
}
}
// Used to implement the _mm_movemask_ps 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/movmskps
"movmsk.ps" => {
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_u32()?;

// Extract the highest bit of `op` and place it in the `i`-th bit of `res`
res |= (op >> 31) << i;
}

this.write_scalar(Scalar::from_u32(res), dest)?;
}
_ => return Ok(EmulateForeignItemResult::NotSupported),
}
Ok(EmulateForeignItemResult::NeedsJumping)
Expand Down
176 changes: 1 addition & 175 deletions src/tools/miri/src/shims/x86/sse2.rs
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Original file line number Diff line number Diff line change
@@ -1,8 +1,4 @@
use rustc_apfloat::{
ieee::{Double, Single},
Float as _,
};
use rustc_middle::mir;
use rustc_apfloat::ieee::Double;
use rustc_middle::ty::layout::LayoutOf as _;
use rustc_middle::ty::Ty;
use rustc_span::Symbol;
Expand Down Expand Up @@ -39,49 +35,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
// 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(&divided, 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
Expand Down Expand Up @@ -118,70 +71,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
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
Expand Down Expand Up @@ -370,25 +259,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
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" => {
Expand Down Expand Up @@ -652,31 +522,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
};
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" => {
Expand Down Expand Up @@ -772,25 +617,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
)?;
}
}
// 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" => {
Expand Down
26 changes: 0 additions & 26 deletions src/tools/miri/src/shims/x86/sse3.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -23,32 +23,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
let unprefixed_name = link_name.as_str().strip_prefix("llvm.x86.sse3.").unwrap();

match unprefixed_name {
// Used to implement the _mm_addsub_ps and _mm_addsub_pd functions.
// Alternatingly add and subtract floating point (f32 or f64) from
// `left` and `right`
"addsub.ps" | "addsub.pd" => {
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)?;

// Even elements are subtracted and odd elements are added.
let op = if i % 2 == 0 { mir::BinOp::Sub } else { mir::BinOp::Add };
let res = this.wrapping_binary_op(op, &left, &right)?;

this.write_immediate(*res, &dest)?;
}
}
// Used to implement the _mm_h{add,sub}_p{s,d} functions.
// Horizontally add/subtract adjacent floating point values
// in `left` and `right`.
Expand Down

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