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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_521, z := (x + y) mod p_521, assuming x and y reduced
// Inputs x[9], y[9]; output z[9]
//
// extern void bignum_add_p521(uint64_t z[static 9], const uint64_t x[static 9],
// const uint64_t y[static 9]);
//
// Standard ARM ABI: X0 = z, X1 = x, X2 = y
// ----------------------------------------------------------------------------
macro_rules! z {
() => {
"x0"
};
}
macro_rules! x {
() => {
"x1"
};
}
macro_rules! y {
() => {
"x2"
};
}
macro_rules! h {
() => {
"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"
};
}
macro_rules! d6 {
() => {
"x11"
};
}
macro_rules! d7 {
() => {
"x12"
};
}
macro_rules! d8 {
() => {
"x13"
};
}
/// Add modulo p_521, z := (x + y) mod p_521, assuming x and y reduced
///
/// Inputs x[9], y[9]; output z[9]
pub(crate) fn bignum_add_p521(z: &mut [u64; 9], x: &[u64; 9], y: &[u64; 9]) {
// SAFETY: inline assembly. see [crate::low::inline_assembly_safety] for safety info.
unsafe {
core::arch::asm!(
// Force carry-in to get s = [d8;d7;d6;d5;d4;d3;d2;d1;d0] = x + y + 1.
// We ignore the carry-out, assuming inputs are reduced so there is none.
Q!(" subs " "xzr, xzr, xzr"),
Q!(" ldp " d0!() ", " d1!() ", [" x!() "]"),
Q!(" ldp " l!() ", " h!() ", [" y!() "]"),
Q!(" adcs " d0!() ", " d0!() ", " l!()),
Q!(" adcs " d1!() ", " d1!() ", " h!()),
Q!(" ldp " d2!() ", " d3!() ", [" x!() ", #16]"),
Q!(" ldp " l!() ", " h!() ", [" y!() ", #16]"),
Q!(" adcs " d2!() ", " d2!() ", " l!()),
Q!(" adcs " d3!() ", " d3!() ", " h!()),
Q!(" ldp " d4!() ", " d5!() ", [" x!() ", #32]"),
Q!(" ldp " l!() ", " h!() ", [" y!() ", #32]"),
Q!(" adcs " d4!() ", " d4!() ", " l!()),
Q!(" adcs " d5!() ", " d5!() ", " h!()),
Q!(" ldp " d6!() ", " d7!() ", [" x!() ", #48]"),
Q!(" ldp " l!() ", " h!() ", [" y!() ", #48]"),
Q!(" adcs " d6!() ", " d6!() ", " l!()),
Q!(" adcs " d7!() ", " d7!() ", " h!()),
Q!(" ldr " d8!() ", [" x!() ", #64]"),
Q!(" ldr " l!() ", [" y!() ", #64]"),
Q!(" adc " d8!() ", " d8!() ", " l!()),
// Now x + y >= p_521 <=> s = x + y + 1 >= 2^521
// Set CF <=> s = x + y + 1 >= 2^521 and make it a mask in l as well
Q!(" subs " l!() ", " d8!() ", #512"),
Q!(" csetm " l!() ", cs"),
// Now if CF is set (and l is all 1s), we want (x + y) - p_521 = s - 2^521
// while otherwise we want x + y = s - 1 (from existing CF, which is nice)
Q!(" sbcs " d0!() ", " d0!() ", xzr"),
Q!(" and " l!() ", " l!() ", #512"),
Q!(" sbcs " d1!() ", " d1!() ", xzr"),
Q!(" sbcs " d2!() ", " d2!() ", xzr"),
Q!(" sbcs " d3!() ", " d3!() ", xzr"),
Q!(" sbcs " d4!() ", " d4!() ", xzr"),
Q!(" sbcs " d5!() ", " d5!() ", xzr"),
Q!(" sbcs " d6!() ", " d6!() ", xzr"),
Q!(" sbcs " d7!() ", " d7!() ", xzr"),
Q!(" sbc " d8!() ", " d8!() ", " l!()),
// Store the result
Q!(" stp " d0!() ", " d1!() ", [" z!() "]"),
Q!(" stp " d2!() ", " d3!() ", [" z!() ", #16]"),
Q!(" stp " d4!() ", " d5!() ", [" z!() ", #32]"),
Q!(" stp " d6!() ", " d7!() ", [" z!() ", #48]"),
Q!(" str " d8!() ", [" z!() ", #64]"),
inout("x0") z.as_mut_ptr() => _,
inout("x1") x.as_ptr() => _,
inout("x2") y.as_ptr() => _,
// clobbers
out("x10") _,
out("x11") _,
out("x12") _,
out("x13") _,
out("x3") _,
out("x4") _,
out("x5") _,
out("x6") _,
out("x7") _,
out("x8") _,
out("x9") _,
)
};
}