[aarch64-port-dev ] [aarch64-port-dev] Compile error in stubGenerator_aarch64.cpp

[Andrew Dinn]

On 09/08/17 14:50, Daniel Stewart wrote:
> Moving this to a different thread to avoid stepping on Andrew’s original
> thread..
> 
> I had been trying to look into the copy_memory() routine (which gets used
> by both disjoint and conjoint copies) to see if interleaving the loads and
> stores (as referenced in the document you mention) obtains better
> performance than all the loads followed by all the stores, as is currently
> implemented.
> 
> However, even when trying to do this only for disjoint copies, I seem to
> have an issue with it. It seems any sort of change I make to the
> stubGenerator_aarch64.cpp file for JDK9 or 10 results in errors compiling.
> 
> Is there some magic a new person to OpenJDK like myself is missing when
> trying to modify this file?
> 
> 
> Here’s the diff I did:
> diff -r 41421b726632 src/cpu/aarch64/vm/stubGenerator_aarch64.cpp
> --- a/src/cpu/aarch64/vm/stubGenerator_aarch64.cpp      Mon Jul 24 17:26:41
> 2017 +0000
> +++ b/src/cpu/aarch64/vm/stubGenerator_aarch64.cpp      Wed Aug 09 13:13:24
> 2017 +0000
> @@ -1231,11 +1231,12 @@
>        __ stpq(v2, v3, Address(dend, -32));
>      } else {
>        __ ldp(t0, t1, Address(s, 0));
> +      __ stp(t0, t1, Address(d, 0));
>        __ ldp(t2, t3, Address(s, 16));
>        __ ldp(t4, t5, Address(send, -32));
>        __ ldp(t6, t7, Address(send, -16));
> 
> -      __ stp(t0, t1, Address(d, 0));
> +//      __ stp(t0, t1, Address(d, 0));
>        __ stp(t2, t3, Address(d, 16));
>        __ stp(t4, t5, Address(dend, -32));
>        __ stp(t6, t7, Address(dend, -16));
> 
> 
> And here’s the error I get:
> Creating support/demos/image/jfc/Metalworks/Metalworks.jar
> Creating interim jimage
> Invalid path in metadata, skipping
> /modules/java.base/META-INF/services/java.nio.file.spi.FileSystemProvider
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/AESCipher$AES128_ECB_NoPadding.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/AESCipher$AES128_OFB_NoPadding.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/AESCipher$OidImpl.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/BlockCipherParamsCore.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/CipherForKeyProtector.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/DESedeWrapCipher.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/GaloisCounterMode.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/KeyGeneratorCore$HmacSHA2KG$SHA224.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/KeyGeneratorCore$HmacSHA2KG.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/OAEPParameters.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBEKey.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBEKeyFactory$PBEWithHmacSHA1AndAES_128.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBEKeyFactory$PBEWithHmacSHA256AndAES_256.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBEKeyFactory$PBEWithMD5AndDES.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBEKeyFactory$PBEWithSHA1AndRC2_40.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBEParameters.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBES2Core$HmacSHA224AndAES_256.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBES2Parameters$HmacSHA384AndAES_128.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBES2Parameters.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBKDF2Core$HmacSHA512.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBKDF2Core.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PBMAC1Core$HmacSHA1.class
> Invalid path in metadata, skipping
> /modules/java.base/com/sun/crypto/provider/PKCS12PBECipherCore$PBEWithSHA1AndRC2_40.class
> …
> Invalid path in metadata, skipping
> /modules/java.logging/java/util/logging/FileHandler$InitializationErrorManager.class
> Invalid path in metadata, skipping
> /modules/java.logging/java/util/logging/Level$1.class
> Invalid path in metadata, skipping
> /modules/java.logging/java/util/logging/Logger.class
> Invalid path in metadata, skipping /modules/java.logging/java/util Invalid
> path in metadata, skipping
> /modules/java.logging/sun/util/logging/resources/logging_sv.class
> Invalid path in metadata, skipping
> /modules/java.logging/sun/util/logging/resources/logging_zh_HK.class
> Creating support/classlist.jar
> gmake[3]: ***
> [/home/stewartd/openjdk/OpenJDK10/hs/build/linux-aarch64-normal-server-release/support/link_opt/classlist]
> Error 1
> gmake[3]: *** Deleting file
> `/home/stewartd/openjdk/OpenJDK10/hs/build/linux-aarch64-normal-server-release/support/link_opt/classlist'
> gmake[2]: *** [generate-link-opt-data] Error 1
> 
> ERROR: Build failed for target 'images' in configuration
> 'linux-aarch64-normal-server-release' (exit code 2) Stopping sjavac server
That change doesn't look like it is guaranteed to be innocuous to me.
Does it do the right thing if you are copying data from an array into
itself? -- say, for example, that you are shuffling String text along in
a byte[] or char[]. Is it possible for the distance between the load and
store addresses to be such that your early write to Address(d, 0) can
change the values read at Address(s, 16/-32/-16)?

I say that because the error messages suggest that what is going wrong
is to do with paths i.e. text.

regards,


Andrew Dinn
-----------
Senior Principal Software Engineer
Red Hat UK Ltd
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