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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
// ----------------------------------------------------------------------------
// Add modulo p_384, z := (x + y) mod p_384, assuming x and y reduced
// Inputs x[6], y[6]; output z[6]
//
// extern void bignum_add_p384(uint64_t z[static 6], const uint64_t x[static 6],
// const uint64_t y[static 6]);
//
// Standard ARM ABI: X0 = z, X1 = x, X2 = y
// ----------------------------------------------------------------------------
macro_rules! z {
() => {
"x0"
};
}
macro_rules! x {
() => {
"x1"
};
}
macro_rules! y {
() => {
"x2"
};
}
macro_rules! c {
() => {
"x3"
};
}
macro_rules! l {
() => {
"x4"
};
}
macro_rules! d0 {
() => {
"x5"
};
}
macro_rules! d1 {
() => {
"x6"
};
}
macro_rules! d2 {
() => {
"x7"
};
}
macro_rules! d3 {
() => {
"x8"
};
}
macro_rules! d4 {
() => {
"x9"
};
}
macro_rules! d5 {
() => {
"x10"
};
}
/// Add modulo p_384, z := (x + y) mod p_384, assuming x and y reduced
///
/// Inputs x[6], y[6]; output z[6]
pub(crate) fn bignum_add_p384(z: &mut [u64; 6], x: &[u64; 6], y: &[u64; 6]) {
// SAFETY: inline assembly. see [crate::low::inline_assembly_safety] for safety info.
unsafe {
core::arch::asm!(
// First just add the numbers as c + [d5; d4; d3; d2; d1; d0]
Q!(" ldp " d0!() ", " d1!() ", [" x!() "]"),
Q!(" ldp " l!() ", " c!() ", [" y!() "]"),
Q!(" adds " d0!() ", " d0!() ", " l!()),
Q!(" adcs " d1!() ", " d1!() ", " c!()),
Q!(" ldp " d2!() ", " d3!() ", [" x!() ", #16]"),
Q!(" ldp " l!() ", " c!() ", [" y!() ", #16]"),
Q!(" adcs " d2!() ", " d2!() ", " l!()),
Q!(" adcs " d3!() ", " d3!() ", " c!()),
Q!(" ldp " d4!() ", " d5!() ", [" x!() ", #32]"),
Q!(" ldp " l!() ", " c!() ", [" y!() ", #32]"),
Q!(" adcs " d4!() ", " d4!() ", " l!()),
Q!(" adcs " d5!() ", " d5!() ", " c!()),
Q!(" adc " c!() ", xzr, xzr"),
// Now compare [d5; d4; d3; d2; d1; d0] with p_384
Q!(" mov " l!() ", #0x00000000ffffffff"),
Q!(" subs " "xzr, " d0!() ", " l!()),
Q!(" mov " l!() ", #0xffffffff00000000"),
Q!(" sbcs " "xzr, " d1!() ", " l!()),
Q!(" mov " l!() ", #0xfffffffffffffffe"),
Q!(" sbcs " "xzr, " d2!() ", " l!()),
Q!(" adcs " "xzr, " d3!() ", xzr"),
Q!(" adcs " "xzr, " d4!() ", xzr"),
Q!(" adcs " "xzr, " d5!() ", xzr"),
// Now CF is set (because of inversion) if (x + y) % 2^384 >= p_384
// Thus we want to correct if either this is set or the original carry c was
Q!(" adcs " c!() ", " c!() ", xzr"),
Q!(" csetm " c!() ", ne"),
// Now correct by subtracting masked p_384
Q!(" mov " l!() ", #0x00000000ffffffff"),
Q!(" and " l!() ", " l!() ", " c!()),
Q!(" subs " d0!() ", " d0!() ", " l!()),
Q!(" eor " l!() ", " l!() ", " c!()),
Q!(" sbcs " d1!() ", " d1!() ", " l!()),
Q!(" mov " l!() ", #0xfffffffffffffffe"),
Q!(" and " l!() ", " l!() ", " c!()),
Q!(" sbcs " d2!() ", " d2!() ", " l!()),
Q!(" sbcs " d3!() ", " d3!() ", " c!()),
Q!(" sbcs " d4!() ", " d4!() ", " c!()),
Q!(" sbc " d5!() ", " d5!() ", " c!()),
// Store the result
Q!(" stp " d0!() ", " d1!() ", [" z!() "]"),
Q!(" stp " d2!() ", " d3!() ", [" z!() ", #16]"),
Q!(" stp " d4!() ", " d5!() ", [" z!() ", #32]"),
inout("x0") z.as_mut_ptr() => _,
inout("x1") x.as_ptr() => _,
inout("x2") y.as_ptr() => _,
// clobbers
out("x10") _,
out("x3") _,
out("x4") _,
out("x5") _,
out("x6") _,
out("x7") _,
out("x8") _,
out("x9") _,
)
};
}