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// generated source. do not edit.
#![allow(non_upper_case_globals, unused_macros, unused_imports)]
use crate::low::macros::*;
// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0 OR ISC OR MIT-0
// ----------------------------------------------------------------------------
// Negate modulo p_384, z := (-x) mod p_384, assuming x reduced
// Input x[6]; output z[6]
//
// extern void bignum_neg_p384(uint64_t z[static 6], const uint64_t x[static 6]);
//
// Standard x86-64 ABI: RDI = z, RSI = x
// Microsoft x64 ABI: RCX = z, RDX = x
// ----------------------------------------------------------------------------
macro_rules! z {
() => {
"rdi"
};
}
macro_rules! x {
() => {
"rsi"
};
}
macro_rules! n0 {
() => {
"rax"
};
}
macro_rules! n1 {
() => {
"rcx"
};
}
macro_rules! n2 {
() => {
"rdx"
};
}
macro_rules! n3 {
() => {
"r8"
};
}
macro_rules! n4 {
() => {
"r9"
};
}
macro_rules! q {
() => {
"r10"
};
}
macro_rules! n0short {
() => {
"eax"
};
}
/// Negate modulo p_384, z := (-x) mod p_384, assuming x reduced
///
/// Input x[6]; output z[6]
pub(crate) fn bignum_neg_p384(z: &mut [u64; 6], x: &[u64; 6]) {
// SAFETY: inline assembly. see [crate::low::inline_assembly_safety] for safety info.
unsafe {
core::arch::asm!(
Q!(" endbr64 " ),
// Or together the input digits and create a bitmask q if this is nonzero, so
// that we avoid doing -0 = p_384 and hence maintain strict modular reduction
Q!(" mov " n0!() ", [" x!() "]"),
Q!(" or " n0!() ", [" x!() "+ 8]"),
Q!(" mov " n1!() ", [" x!() "+ 16]"),
Q!(" or " n1!() ", [" x!() "+ 24]"),
Q!(" mov " n2!() ", [" x!() "+ 32]"),
Q!(" or " n2!() ", [" x!() "+ 40]"),
Q!(" or " n0!() ", " n1!()),
Q!(" or " n0!() ", " n2!()),
Q!(" neg " n0!()),
Q!(" sbb " q!() ", " q!()),
// Let [q;n4;n3;n2;n1;n0] = if q then p_384 else 0
Q!(" mov " n0short!() ", 0x00000000ffffffff"),
Q!(" and " n0!() ", " q!()),
Q!(" mov " n1!() ", 0xffffffff00000000"),
Q!(" and " n1!() ", " q!()),
Q!(" mov " n2!() ", 0xfffffffffffffffe"),
Q!(" and " n2!() ", " q!()),
Q!(" mov " n3!() ", " q!()),
Q!(" mov " n4!() ", " q!()),
// Do the subtraction
Q!(" sub " n0!() ", [" x!() "]"),
Q!(" sbb " n1!() ", [" x!() "+ 8]"),
Q!(" sbb " n2!() ", [" x!() "+ 16]"),
Q!(" sbb " n3!() ", [" x!() "+ 24]"),
Q!(" sbb " n4!() ", [" x!() "+ 32]"),
Q!(" sbb " q!() ", [" x!() "+ 40]"),
// Write back
Q!(" mov " "[" z!() "], " n0!()),
Q!(" mov " "[" z!() "+ 8], " n1!()),
Q!(" mov " "[" z!() "+ 16], " n2!()),
Q!(" mov " "[" z!() "+ 24], " n3!()),
Q!(" mov " "[" z!() "+ 32], " n4!()),
Q!(" mov " "[" z!() "+ 40], " q!()),
inout("rdi") z.as_mut_ptr() => _,
inout("rsi") x.as_ptr() => _,
// clobbers
out("r10") _,
out("r8") _,
out("r9") _,
out("rax") _,
out("rcx") _,
out("rdx") _,
)
};
}