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Use inline asm for _mm_clmulepi64_si128

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This is a lot more compact and significantly faster
This commit is contained in:
bjorn3 2023-11-11 21:04:39 +00:00
parent dc60334777
commit 813f8b4fd0
1 changed files with 30 additions and 55 deletions
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85
src/intrinsics/llvm_x86.rs
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@ -719,66 +719,41 @@ fn select4(
}
"llvm.x86.pclmulqdq" => {
// FIXME use inline asm
// https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=_mm_clmulepi64_si128&ig_expand=772
intrinsic_args!(fx, args => (a, b, imm8); intrinsic);
intrinsic_args!(fx, args => (a, b, _imm8); intrinsic);
assert_eq!(a.layout(), b.layout());
let layout = a.layout();
let a = a.load_scalar(fx);
let b = b.load_scalar(fx);
let (lane_count, lane_ty) = layout.ty.simd_size_and_type(fx.tcx);
let (ret_lane_count, ret_lane_ty) = ret.layout().ty.simd_size_and_type(fx.tcx);
assert_eq!(lane_ty, fx.tcx.types.i64);
assert_eq!(ret_lane_ty, fx.tcx.types.i64);
assert_eq!(lane_count, 2);
assert_eq!(ret_lane_count, 2);
let imm8 = if let Some(imm8) = crate::constant::mir_operand_get_const_val(fx, &args[2])
{
imm8
} else {
fx.tcx.sess.span_fatal(
span,
"Index argument for `_mm_clmulepi64_si128` is not a constant",
);
};
let imm8 = imm8.load_scalar(fx);
let imm8 = imm8.try_to_u8().unwrap_or_else(|_| panic!("kind not scalar: {:?}", imm8));
let control0 = fx.bcx.ins().band_imm(imm8, 0b0000_0001);
let a_lane0 = a.value_lane(fx, 0).load_scalar(fx);
let a_lane1 = a.value_lane(fx, 1).load_scalar(fx);
let temp1 = fx.bcx.ins().select(control0, a_lane1, a_lane0);
let control4 = fx.bcx.ins().band_imm(imm8, 0b0001_0000);
let b_lane0 = b.value_lane(fx, 0).load_scalar(fx);
let b_lane1 = b.value_lane(fx, 1).load_scalar(fx);
let temp2 = fx.bcx.ins().select(control4, b_lane1, b_lane0);
fn extract_bit(fx: &mut FunctionCx<'_, '_, '_>, val: Value, bit: i64) -> Value {
let tmp = fx.bcx.ins().ushr_imm(val, bit);
fx.bcx.ins().band_imm(tmp, 1)
}
let mut res1 = fx.bcx.ins().iconst(types::I64, 0);
for i in 0..=63 {
let x = extract_bit(fx, temp1, 0);
let y = extract_bit(fx, temp2, i);
let mut temp = fx.bcx.ins().band(x, y);
for j in 1..=i {
let x = extract_bit(fx, temp1, j);
let y = extract_bit(fx, temp2, i - j);
let z = fx.bcx.ins().band(x, y);
temp = fx.bcx.ins().bxor(temp, z);
}
let temp = fx.bcx.ins().ishl_imm(temp, i);
res1 = fx.bcx.ins().bor(res1, temp);
}
ret.place_lane(fx, 0).to_ptr().store(fx, res1, MemFlags::trusted());
let mut res2 = fx.bcx.ins().iconst(types::I64, 0);
for i in 64..=127 {
let mut temp = fx.bcx.ins().iconst(types::I64, 0);
for j in i - 63..=63 {
let x = extract_bit(fx, temp1, j);
let y = extract_bit(fx, temp2, i - j);
let z = fx.bcx.ins().band(x, y);
temp = fx.bcx.ins().bxor(temp, z);
}
let temp = fx.bcx.ins().ishl_imm(temp, i);
res2 = fx.bcx.ins().bor(res2, temp);
}
ret.place_lane(fx, 1).to_ptr().store(fx, res2, MemFlags::trusted());
codegen_inline_asm_inner(
fx,
&[InlineAsmTemplatePiece::String(format!("pclmulqdq xmm0, xmm1, {imm8}"))],
&[
CInlineAsmOperand::InOut {
reg: InlineAsmRegOrRegClass::Reg(InlineAsmReg::X86(X86InlineAsmReg::xmm0)),
_late: true,
in_value: a,
out_place: Some(ret),
},
CInlineAsmOperand::In {
reg: InlineAsmRegOrRegClass::Reg(InlineAsmReg::X86(X86InlineAsmReg::xmm1)),
value: b,
},
],
InlineAsmOptions::NOSTACK | InlineAsmOptions::PURE | InlineAsmOptions::NOMEM,
);
}
"llvm.x86.aesni.aeskeygenassist" => {