RFR: 8248238: Implementation of JEP: Windows AArch64 Support [v2]

[Bernhard Urban-Forster]

On Fri, 18 Sep 2020 18:38:34 GMT, Bernhard Urban-Forster <burban at openjdk.org> wrote:

>> Our linux-aarch64 build fails with this:
>> cc: error: unrecognized command line option '-std=c++14'
>> when compiling build/linux-aarch64/buildjdk/hotspot/variant-server/libjvm/objs/precompiled/precompiled.hpp.gch
>> 
>> I'm trying to configure a windows-aarch64 build, but it fails on fixpath. Is this something you are also experiencing,
>> and if so, how are you addressing it?
>
> Hey @erikj79, thank you so much for giving it a try!
> 
>> Our linux-aarch64 build fails with this:
>> cc: error: unrecognized command line option '-std=c++14'
>> when compiling build/linux-aarch64/buildjdk/hotspot/variant-server/libjvm/objs/precompiled/precompiled.hpp.gch
> 
> Hmm, that's interesting. What environment is that exactly? What `configure` line are you using there? We have tested on
> such a system: $ cat /etc/issue
> Ubuntu 19.10 \n \l
> $ bash configure --with-boot-jdk=/home/beurba/work/jdk-16+13 --with-jtreg
> $ make clean CONF=linux-aarch64-server-release
> $ make images JOBS=255 LOG=info CONF=linux-aarch64-server-release
> $ ./build/linux-aarch64-server-release/images/jdk/bin/java -XshowSettings:properties -version 2>&1 | grep aarch64
>     java.home = /home/beurba/work/jdk/build/linux-aarch64-server-release/images/jdk
>     os.arch = aarch64
>     sun.boot.library.path = /home/beurba/work/jdk/build/linux-aarch64-server-release/images/jdk/lib
> --------------------------------------------------------
>> I'm trying to configure a windows-aarch64 build, but it fails on fixpath. Is this something you are also experiencing,
>> and if so, how are you addressing it?
> 
> Yes. As far as I understand, the problem is that `fixpath.exe` isn't built properly when doing cross-compiling on
> Windows targets (as it hasn't been a thing so far). We use a workaround internally
> https://gist.github.com/lewurm/c099a4b5fcd8a182510cbdeebcb41f77 , but a proper solution is under discussion on
> build-dev: https://mail.openjdk.java.net/pipermail/build-dev/2020-July/027872.html

> _Mailing list message from [Andrew Haley](mailto:aph at redhat.com) on [build-dev](mailto:build-dev at openjdk.java.net):_
> 
> On 18/09/2020 11:14, Monica Beckwith wrote:
> 
> > This is a continuation of https://mail.openjdk.java.net/pipermail/aarch64-port-dev/2020-August/009566.html
> 
> The diffs in assembler_aarch64.cpp are mostly spurious. Please try this.


Thank you Andrew. Is the goal to reduce the patch diff in `assembler_aarch64.cpp`? If so, we need to get rid of the
retry in your patch to avoid additional calls to `random`, e.g. something like this (the diff for the generated part
would look indeed nicer with that:  https://gist.github.com/lewurm/2e7b0e00447696c75e00febb83034ba1 ):

--- a/src/hotspot/cpu/aarch64/aarch64-asmtest.py
+++ b/src/hotspot/cpu/aarch64/aarch64-asmtest.py
@@ -13,6 +13,8 @@ class Register(Operand):

     def generate(self):
         self.number = random.randint(0, 30)
+        if self.number == 18:
+            self.number = 17
         return self

     def astr(self, prefix):
@@ -37,6 +39,8 @@ class GeneralRegisterOrZr(Register):

     def generate(self):
         self.number = random.randint(0, 31)
+        if self.number == 18:
+            self.number = 16
         return self

     def astr(self, prefix = ""):
@@ -54,6 +58,8 @@ class GeneralRegisterOrZr(Register):
 class GeneralRegisterOrSp(Register):
     def generate(self):
         self.number = random.randint(0, 31)
+        if self.number == 18:
+            self.number = 15
         return self

     def astr(self, prefix = ""):
@@ -1331,7 +1337,7 @@ generate(SpecialCases, [["ccmn",   "__ ccmn(zr, zr, 3u, Assembler::LE);",
                         ["st1w",   "__ sve_st1w(z0, __ S, p1, Address(r0, 7));",         "st1w\t{z0.s}, p1, [x0, #7, MUL VL]"],
                         ["st1b",   "__ sve_st1b(z0, __ B, p2, Address(sp, r1));",        "st1b\t{z0.b}, p2, [sp, x1]"],
                         ["st1h",   "__ sve_st1h(z0, __ H, p3, Address(sp, r8));",        "st1h\t{z0.h}, p3, [sp, x8, LSL #1]"],
-                        ["st1d",   "__ sve_st1d(z0, __ D, p4, Address(r0, r18));",       "st1d\t{z0.d}, p4, [x0, x18, LSL #3]"],
+                        ["st1d",   "__ sve_st1d(z0, __ D, p4, Address(r0, r17));",       "st1d\t{z0.d}, p4, [x0, x17,
LSL #3]"],
                         ["ldr",    "__ sve_ldr(z0, Address(sp));",                       "ldr\tz0, [sp]"],
                         ["ldr",    "__ sve_ldr(z31, Address(sp, -256));",                "ldr\tz31, [sp, #-256, MUL VL]"],
                         ["str",    "__ sve_str(z8, Address(r8, 255));",                  "str\tz8, [x8, #255, MUL VL]"],

-------------

PR: https://git.openjdk.java.net/jdk/pull/212