Implementation notes: riscv64, hifiveunleashedriscv, crypto_scalarmult/curve25519

Computer: hifiveunleashedriscv
Architecture: riscv64
CPU ID: unknown CPU ID
SUPERCOP version: 20191221
Operation: crypto_scalarmult
Primitive: curve25519

Time	Object size	Test size	Implementation	Compiler	Benchmark date	SUPERCOP version
3985471	25740 0 0	39699 736 1560	`donna_c64`	`gcc_-march=rv64gc_-O3_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
4122632	21176 0 0	33709 736 1560	`donna_c64`	`gcc_-march=rv64gc_-O2_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
4161203	20180 0 0	32121 720 1560	`donna_c64`	`gcc_-march=rv64gc_-Os_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
4548780	19686 0 0	32021 736 1560	`donna_c64`	`gcc_-march=rv64gc_-O_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
7960660	6126 0 0	19841 736 1560	`ref10`	`gcc_-march=rv64gc_-O3_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
7961164	6128 0 0	18417 736 1560	`ref10`	`gcc_-march=rv64gc_-O2_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
8058918	5232 0 0	16913 720 1560	`ref10`	`gcc_-march=rv64gc_-Os_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
8445548	5404 0 0	17479 736 1560	`ref10`	`gcc_-march=rv64gc_-O_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
144885690	3916 0 0	17631 736 1560	`ref`	`gcc_-march=rv64gc_-O3_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
146926282	3012 0 0	15281 736 1560	`ref`	`gcc_-march=rv64gc_-O2_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
158186230	2816 0 0	14481 720 1560	`ref`	`gcc_-march=rv64gc_-Os_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221
179599537	3260 0 0	15323 736 1560	`ref`	`gcc_-march=rv64gc_-O_-fomit-frame-pointer_-fwrapv_-fPIC_-fPIE`	20191231	20191221

Compiler output

Implementation: donna_c64
Security model: unknown
Compiler: gcc -march=rv64gc -O2 -fomit-frame-pointer -fwrapv -fPIC -fPIE

smult.c: smult.c:149:1: warning: always_inline function might not be inlinable [-Wattributes]
smult.c: 149 | fsquare_times(felem output, const felem in, limb count) {
smult.c: | ^~~~~~~~~~~~~
smult.c: smult.c:100:1: warning: always_inline function might not be inlinable [-Wattributes]
smult.c: 100 | fmul(felem output, const felem in2, const felem in) {
smult.c: | ^~~~
smult.c: smult.c:70:1: warning: always_inline function might not be inlinable [-Wattributes]
smult.c: 70 | fscalar_product(felem output, const felem in, const limb scalar) {
smult.c: | ^~~~~~~~~~~~~~~
smult.c: smult.c:56:1: warning: always_inline function might not be inlinable [-Wattributes]
smult.c: 56 | fdifference_backwards(felem out, const felem in) {
smult.c: | ^~~~~~~~~~~~~~~~~~~~~
smult.c: smult.c:41:1: warning: always_inline function might not be inlinable [-Wattributes]
smult.c: 41 | fsum(limb *output, const limb *in) {
smult.c: | ^~~~

Number of similar (compiler,implementation) pairs: 4, namely:

Compiler	Implementations
gcc -march=rv64gc -O2 -fomit-frame-pointer -fwrapv -fPIC -fPIE	donna_c64
gcc -march=rv64gc -O3 -fomit-frame-pointer -fwrapv -fPIC -fPIE	donna_c64
gcc -march=rv64gc -O -fomit-frame-pointer -fwrapv -fPIC -fPIE	donna_c64
gcc -march=rv64gc -Os -fomit-frame-pointer -fwrapv -fPIC -fPIE	donna_c64