Amd aocc support (#1684)

Added AMD AOCC Compiler support to WRF 

TYPE: choose one of [new feature]

KEYWORDS: AMD, AOCC, Compiler Support, ZEN Architecture, Configure

SOURCE:  amd-toolchain-support@github.com 

DESCRIPTION OF CHANGES:
Problem: Added AMD AOCC Compiler Support
Earlier there is no support for AMD AOCC Complier. Now we have added support. 

Solution:
Added AMD AOCC Compiler support to configure using stanzas. 

LIST OF MODIFIED FILES: 
M       arch/configure.defaults

TESTS CONDUCTED: 
1. Compiled and tested with AOCC Compiler. Functional test with AOCC 3.2.0 is done.
2. Passed regression tests.

RELEASE NOTE: Provided AMD AOCC Compiler support at the time of configuring WRF for AMD Architectures including Zen1, Zen2 and Zen3.

arch/configure.defaults

@@ -2068,6 +2068,59 @@ RLFLAGS         =
 CC_TOOLS        =      $(SCC)
 NETCDFPAR_BUILD	=      CONFIGURE_NETCDFPAR_BUILD
 
+###########################################################
+#ARCH    AMD Linux x86_64, AOCC flang compiler with AOCC clang  #serial smpar dmpar dm+sm
+# Supported AMDARCH are znver1, znver2 and znver3 for ZEN1, ZEN2 and ZEN3 respectively
+# For optimized AMDFCFLAGS and AMDLDFLAGS, please reach out to toolchainsupport@amd.com
+#
+
+DESCRIPTION     =       AMD ($SFC/$SCC) :  AMD ZEN1/ ZEN2/ ZEN3 Architectures
+DMPARALLEL      =       1
+OMPCPP          =       -D_OPENMP
+OMP             =       -fopenmp
+OMPCC           =       -fopenmp
+SFC             =       flang
+SCC             =       clang
+CCOMP           =       clang
+DM_FC           =       mpif90
+DM_CC           =       mpicc
+FC              =       CONFIGURE_FC
+CC              =       CONFIGURE_CC
+LD              =       $(FC)
+RWORDSIZE       =       CONFIGURE_RWORDSIZE
+
+AMDARCH         =       -march=znver3
+AMDMATHLIB      =       -fveclib=AMDLIBM
+AMDLDFLAGS      =       -Wl,-mllvm -Wl,-enable-loop-reversal -Wl,-mllvm -Wl,-enable-gather -Wl,-mllvm -Wl,-vectorize-noncontigous-memory-aggressively
+AMDFCFLAGS      =
+
+PROMOTION       =       #-fdefault-real-8
+ARCH_LOCAL      =       -DNONSTANDARD_SYSTEM_SUBR  -DWRF_USE_CLM -DRPC_TYPES=2
+CFLAGS_LOCAL    =       -w -c -m64 -Ofast -ffast-math $(AMDARCH)
+LDFLAGS_LOCAL   =       -m64 -Ofast -Mstack_arrays $(AMDARCH) $(AMDLDFLAGS) $(AMDMATHLIB) -lamdlibm -lomp
+CPLUSPLUSLIB    =
+ESMF_LDFLAG     =       $(CPLUSPLUSLIB)
+FCOPTIM         =       -Ofast -ffast-math $(AMDARCH) -Mbyteswapio -Mstack_arrays -ftree-vectorize -Mbyteswapio -funroll-loops -finline-aggressive -finline-hint-functions $(AMDMATHLIB) $(AMDFCFLAGS)
+FCREDUCEDOPT    =       -O3 $(AMDARCH) -ffast-math -Mstack_arrays -DFCREDUCEDOPT
+FCNOOPT         =       -O0
+FCDEBUG         =       # -g $(FCNOOPT)
+FORMAT_FIXED    =       -Mfixed
+FORMAT_FREE     =       -Mfreeform
+FCSUFFIX        =
+BYTESWAPIO      =       -Mbyteswapio
+FCBASEOPTS_NO_G =       -w $(FORMAT_FREE) $(BYTESWAPIO)
+FCBASEOPTS      =       -Ofast -ffast-math $(FCBASEOPTS_NO_G) $(FCDEBUG)
+MODULE_SRCH_FLAG=
+TRADFLAG        =       -traditional
+CPP             =       /lib/cpp -P
+AR              =       llvm-ar
+ARFLAGS         =       ru
+M4              =       m4
+RANLIB          =       llvm-ranlib
+RLFLAGS         =
+CC_TOOLS        =       $(SCC)
+NETCDFPAR_BUILD =       CONFIGURE_NETCDFPAR_BUILD
+
 #insert new stanza here
 
 ###########################################################