This implementation utilizes the same registers found in the reference
implementation, aiming to produce a minimal semantic diff between the
Avo-generated output and the original hand-written assembly.
To verify the Avo implementation, the reference and Avo-generated
assembly files are fed to `go tool asm`, capturing the debug output into
corresponding temp files. The debug output contains supplementary
metadata (line numbers, instruction offsets, and source file references)
that must be removed in order to obtain a semantic diff of the two
files. This is accomplished via a small utility script written in awk.
Commands used to verify Avo output:
GOROOT=$(go env GOROOT)
ASM_PATH="internal/poly1305/sum_amd64.s"
REFERENCE="b2d3a6a4b4d36521cd7f653879cf6981e7c5c340"
go tool asm -o /dev/null -I "$GOROOT"/src/runtime -debug \
<(git cat-file -p "$REFERENCE:$ASM_PATH") \
> /tmp/reference.s
go tool asm -o /dev/null -I "$GOROOT"/src/runtime -debug \
"$ASM_PATH" \
> /tmp/avo.s
normalize(){
awk '{
$1=$2=$3="";
print substr($0,4)
}'
}
diff <(normalize < /tmp/reference.s) <(normalize < /tmp/avo.s)
Change-Id: I80212c95d1b05335d7f6b73a3030b6f812f6105b
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/600035
Reviewed-by: Roland Shoemaker <roland@golang.org>
Reviewed-by: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Roland Shoemaker
Garrett Bodley