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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
// ----------------------------------------------------------------------------
// Given table: uint64_t[height*16], copy table[idx*16...(idx+1)*16-1]
// into z[0..row-1].
// This function is constant-time with respect to the value of `idx`. This is
// achieved by reading the whole table and using the bit-masking to get the
// `idx`-th row.
//
// extern void bignum_copy_row_from_table_16
// (uint64_t *z, const uint64_t *table, uint64_t height, uint64_t idx);
//
// Initial version written by Hanno Becker
// Standard ARM ABI: X0 = z, X1 = table, X2 = height, X3 = idx
// ----------------------------------------------------------------------------
// *****************************************************
// Main code
// *****************************************************
macro_rules! z {
() => {
"x0"
};
}
macro_rules! tbl {
() => {
"x1"
};
}
macro_rules! height {
() => {
"x2"
};
}
macro_rules! idx {
() => {
"x3"
};
}
macro_rules! mask {
() => {
"x5"
};
}
macro_rules! cnt {
() => {
"x6"
};
}
macro_rules! ventry0 {
() => {
"v20"
};
}
macro_rules! qentry0 {
() => {
"q20"
};
}
macro_rules! ventry1 {
() => {
"v21"
};
}
macro_rules! qentry1 {
() => {
"q21"
};
}
macro_rules! ventry2 {
() => {
"v22"
};
}
macro_rules! qentry2 {
() => {
"q22"
};
}
macro_rules! ventry3 {
() => {
"v23"
};
}
macro_rules! qentry3 {
() => {
"q23"
};
}
macro_rules! ventry4 {
() => {
"v24"
};
}
macro_rules! qentry4 {
() => {
"q24"
};
}
macro_rules! ventry5 {
() => {
"v25"
};
}
macro_rules! qentry5 {
() => {
"q25"
};
}
macro_rules! ventry6 {
() => {
"v26"
};
}
macro_rules! qentry6 {
() => {
"q26"
};
}
macro_rules! ventry7 {
() => {
"v27"
};
}
macro_rules! qentry7 {
() => {
"q27"
};
}
macro_rules! ventry8 {
() => {
"v28"
};
}
macro_rules! vtmp {
() => {
"v16"
};
}
macro_rules! qtmp {
() => {
"q16"
};
}
macro_rules! vmask {
() => {
"v17"
};
}
/// Given table: uint64_t[height*16], copy table[idx*16...(idx+1)*16-1]
///
/// into z[0..row-1].
/// This function is constant-time with respect to the value of `idx`. This is
/// achieved by reading the whole table and using the bit-masking to get the
/// `idx`-th row.
pub(crate) fn bignum_copy_row_from_table_16(z: &mut [u64], table: &[u64], height: u64, index: u64) {
debug_assert!(z.len() == 16);
// SAFETY: inline assembly. see [crate::low::inline_assembly_safety] for safety info.
unsafe {
core::arch::asm!(
// Clear accumulator
// Zeroing can be done via xor, but xor isn't formalized yet.
Q!(" dup " ventry0!() ".2d, xzr"),
Q!(" mov " ventry1!() ".16b, " ventry0!() ".16b"),
Q!(" mov " ventry2!() ".16b, " ventry0!() ".16b"),
Q!(" mov " ventry3!() ".16b, " ventry0!() ".16b"),
Q!(" mov " ventry4!() ".16b, " ventry0!() ".16b"),
Q!(" mov " ventry5!() ".16b, " ventry0!() ".16b"),
Q!(" mov " ventry6!() ".16b, " ventry0!() ".16b"),
Q!(" mov " ventry7!() ".16b, " ventry0!() ".16b"),
Q!(" mov " cnt!() ", #0"),
Q!(Label!("bignum_copy_row_from_table_16_loop", 2) ":"),
// Compute mask: Check if current index matches target index
Q!(" subs " "xzr, " cnt!() ", " idx!()),
Q!(" cinv " mask!() ", xzr, eq"),
Q!(" dup " vmask!() ".2d, " mask!()),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 0]"),
Q!(" bit " ventry0!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 1]"),
Q!(" bit " ventry1!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 2]"),
Q!(" bit " ventry2!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 3]"),
Q!(" bit " ventry3!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 4]"),
Q!(" bit " ventry4!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 5]"),
Q!(" bit " ventry5!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 6]"),
Q!(" bit " ventry6!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" ldr " qtmp!() ", [" tbl!() ", #16 * 7]"),
Q!(" bit " ventry7!() ".16b, " vtmp!() ".16b, " vmask!() ".16b"),
Q!(" add " tbl!() ", " tbl!() ", #16 * 8"),
Q!(" add " cnt!() ", " cnt!() ", #1"),
Q!(" subs " "xzr, " height!() ", " cnt!()),
Q!(" b.ne " Label!("bignum_copy_row_from_table_16_loop", 2, Before)),
Q!(Label!("bignum_copy_row_from_table_16_end", 3) ":"),
Q!(" str " qentry0!() ", [" z!() ", #16 * 0]"),
Q!(" str " qentry1!() ", [" z!() ", #16 * 1]"),
Q!(" str " qentry2!() ", [" z!() ", #16 * 2]"),
Q!(" str " qentry3!() ", [" z!() ", #16 * 3]"),
Q!(" str " qentry4!() ", [" z!() ", #16 * 4]"),
Q!(" str " qentry5!() ", [" z!() ", #16 * 5]"),
Q!(" str " qentry6!() ", [" z!() ", #16 * 6]"),
Q!(" str " qentry7!() ", [" z!() ", #16 * 7]"),
inout("x0") z.as_mut_ptr() => _,
inout("x1") table.as_ptr() => _,
inout("x2") height => _,
inout("x3") index => _,
// clobbers
out("v16") _,
out("v17") _,
out("v20") _,
out("v21") _,
out("v22") _,
out("v23") _,
out("v24") _,
out("v25") _,
out("v26") _,
out("v27") _,
out("x5") _,
out("x6") _,
)
};
}