On Tue, 21 Sep 2021 21:58:48 GMT, Claes Redestad <redes...@openjdk.org> wrote:
> This patch extends the `ISO_8859_1.implEncodeISOArray` intrinsic on x86 to
> work also for ASCII encoding, which makes for example the `UTF_8$Encoder`
> perform on par with (or outperform) similarly getting charset encoded bytes
> from a String. The former took a small performance hit in JDK 9, and the
> latter improved greatly in the same release.
>
> Extending the `EncodeIsoArray` intrinsics on other platforms should be
> possible, but I'm unfamiliar with the macro assembler in general and unlike
> the x86 intrinsic they don't use a simple vectorized mask to implement the
> latin-1 check. For example aarch64 seem to filter out the low bytes and then
> check if there's any bits set in the high bytes. Clever, but very different
> to the 0xFF80 2-byte mask that an ASCII test wants.
Very nice. The changes look good to me, just added some minor comments.
Should we remove the "iso" part from the method/class names?
src/hotspot/cpu/x86/x86_32.ad line 12218:
> 12216: instruct encode_ascii_array(eSIRegP src, eDIRegP dst, eDXRegI len,
> 12217: regD tmp1, regD tmp2, regD tmp3, regD tmp4,
> 12218: eCXRegI tmp5, eAXRegI result, eFlagsReg cr)
> %{
Indentation is wrong.
src/hotspot/cpu/x86/x86_32.ad line 12223:
> 12221: effect(TEMP tmp1, TEMP tmp2, TEMP tmp3, TEMP tmp4, USE_KILL src,
> USE_KILL dst, USE_KILL len, KILL tmp5, KILL cr);
> 12222:
> 12223: format %{ "Encode array $src,$dst,$len -> $result // KILL ECX,
> EDX, $tmp1, $tmp2, $tmp3, $tmp4, ESI, EDI " %}
You might want to change the opto assembly comment to "Encode ascii array" (and
to "Encode iso array" above). Same on 64-bit.
src/hotspot/share/opto/intrinsicnode.hpp line 171:
> 169:
> 170:
> //------------------------------EncodeISOArray--------------------------------
> 171: // encode char[] to byte[] in ISO_8859_1
Comment should be adjusted to `... in ISO_8859_1 or ASCII`.
-------------
Marked as reviewed by thartmann (Reviewer).
PR: https://git.openjdk.java.net/jdk/pull/5621
