openjdk8: mips* support

Builds for all mips* platforms, using the zero backend. A mips port
properly is in process but has been "getting close to ready" for years
now, so we are using the much more tested zero backend.

mipshf had a branch jump error (mips hates super large branch jumps).
This is a known bug that is not going to be fixed very easily. To
workaround this, I reduced the jump by ~400 lines of assembly by
compiling with -Os, enough to make the jump close enough.

[ci skip]

srcpkgs/openjdk8/patches/104_mips-support.patch

@@ -0,0 +1,69 @@
+# DP: Add support for zero architectures alpha, m68k, mips*, sh4
+
+Sourced from https://bazaar.launchpad.net/~openjdk/openjdk/openjdk8/view/head:/debian/patches/zero-architectures.diff
+
+--- openjdk/common/autoconf/platform.m4
++++ openjdk/common/autoconf/platform.m4
+@@ -54,6 +60,42 @@ AC_DEFUN([PLATFORM_EXTRACT_VARS_FROM_CPU
+       VAR_CPU_BITS=64
+       VAR_CPU_ENDIAN=little
+       ;;
++    mips)
++      VAR_CPU=mips
++      VAR_CPU_ARCH=mips
++      VAR_CPU_BITS=32
++      VAR_CPU_ENDIAN=big
++      ;;
++    mipsel)
++      VAR_CPU=mipsel
++      VAR_CPU_ARCH=mipsel
++      VAR_CPU_BITS=32
++      VAR_CPU_ENDIAN=little
++      ;;
++    mipsn32)
++      VAR_CPU=mipsn32
++      VAR_CPU_ARCH=mipsn32
++      VAR_CPU_BITS=32
++      VAR_CPU_ENDIAN=big
++      ;;
++    mipsn32el)
++      VAR_CPU=mipsn32el
++      VAR_CPU_ARCH=mipsn32el
++      VAR_CPU_BITS=32
++      VAR_CPU_ENDIAN=little
++      ;;
++    mips64)
++      VAR_CPU=mips64
++      VAR_CPU_ARCH=mips64
++      VAR_CPU_BITS=64
++      VAR_CPU_ENDIAN=big
++      ;;
++    mips64el)
++      VAR_CPU=mips64el
++      VAR_CPU_ARCH=mips64el
++      VAR_CPU_BITS=64
++      VAR_CPU_ENDIAN=little
++      ;;
+     powerpc)
+       VAR_CPU=ppc
+       VAR_CPU_ARCH=ppc
+@@ -373,6 +433,8 @@ AC_DEFUN([PLATFORM_SETUP_LEGACY_VARS],
+ 
+   # ZERO_ARCHDEF is used to enable architecture-specific code
+   case "${OPENJDK_TARGET_CPU}" in
++    mips|mipsn32|mips64)  ZERO_ARCHDEF=MIPS ;;
++    mipsel|mipsn32el|mips64el)  ZERO_ARCHDEF=MIPSEL ;;
+     ppc)     ZERO_ARCHDEF=PPC32 ;;
+     ppc64)   ZERO_ARCHDEF=PPC64 ;;
+     s390*)   ZERO_ARCHDEF=S390  ;;
+--- openjdk/common/autoconf/flags.m4
++++ openjdk/common/autoconf/flags.m4
+@@ -827,6 +827,8 @@ AC_DEFUN_ONCE([FLAGS_SETUP_COMPILER_FLAG
+     *)
+       ZERO_ARCHFLAG="${COMPILER_TARGET_BITS_FLAG}${OPENJDK_TARGET_CPU_BITS}"
+   esac
++  # use the default for the package builds
++  ZERO_ARCHFLAG=""
+   FLAGS_COMPILER_CHECK_ARGUMENTS([$ZERO_ARCHFLAG], [], [ZERO_ARCHFLAG=""])
+   AC_SUBST(ZERO_ARCHFLAG)
+ 

srcpkgs/openjdk8/template

@@ -67,7 +67,7 @@ desc_option_docs="Build documentation"
 # no hotspot JIT for arm32 and ppc32
 case "$XBPS_TARGET_MACHINE" in
 	ppc64*) ;;
-	arm*|ppc*) _use_zero=yes ;;
+	arm*|ppc*|mips*) _use_zero=yes ;;
 esac
 
 # specifically do not enable docs because with zero it takes hours
@@ -185,12 +185,18 @@ do_configure() {
 	CFLAGS=${CFLAGS/-D_FORTIFY_SOURCE=2/}
 	CXXFLAGS=${CXXFLAGS/-D_FORTIFY_SOURCE=2/}
 
-	# force ELFv2 for ppc64 just in case
 	case "$XBPS_TARGET_MACHINE" in
+		# force ELFv2 for ppc64 just in case
 		ppc64*)
 			CFLAGS+=" -DABI_ELFv2"
 			CXXFLAGS+=" -DABI_ELFv2"
 			;;
+		# with normal -O2 on mipshf there is a too-large jump which causes the
+		# assembler to fail. optimising for size means the jump is made smaller
+		mips*hf*)
+			CFLAGS+=" -Os"
+			CXXFLAGS+=" -Os"
+			;;
 	esac
 
 	configure_args=${configure_args/--with-libtool-sysroot=\/usr\/[a-z0-9]*-linux-[a-z]*/}