configuration_rng.mk

# RNG_IMPLEMENTATION= : Choose which random number generator algorithm to use. If unset, then it chooses an unspecified default,
#   possibly depending on platform, architecture, and optimization flags.
#     The random number generator chosen has a surprisingly outsized influence on the throughput of recipesAtHome, which is why there
#     are so many options available
#   Supported values are: default, system, lehmer, wyhash, xoshiro, lcg, mersenne_twister, subtract_with_carry, pcg, pcg_cpp
#   For furhter documentation, see RNG_Options.txt

# "canonical" name is always the first one
RECOGNIZED_SYSTEM_RNG_OPTIONS:=system sys rand builtin stdlib
RECOGNIZED_LEHMER_RNG_OPTIONS:=lehmer lehmer64
RECOGNIZED_WYHASH_RNG_OPTIONS:=wyhash wyhash64 wyhash-lemire wyhash64-lemire wyrand wyrand-lemire
RECOGNIZED_XOSHIRO_RNG_OPTIONS:=xoshiro xoshiro_cpp xoshiro-cpp
RECOGNIZED_LCG_RNG_OPTIONS:=lcg lcg-cpp linear_congruential_engine linear_congruential_engine-cpp
RECOGNIZED_MERSENNE_TWISTER_OPTIONS:=mersenne_twister mersenne_twister-cpp mersenne_twister_engine mersenne_twister_engine_cpp
RECOGNIZED_SUBTRACT_WITH_CARRY_OPTIONS:=subtract_with_carry subtract_with_carry-cpp subtract_with_carry_engine subtract_with_carry_engine-cpp lagged_fibonacci lagged_fibonacci-cpp
RECOGNIZED_PCG_OPTIONS:=pcg pcg_c pcg-c pcg-random
RECOGNIZED_PCG_CPP_OPTIONS:=pcg_cpp pcg-cpp pcg-random-cpp
 
_RECOGNIZED_RNG_OPTIONS_VARIABLES:=RECOGNIZED_SYSTEM_RNG_OPTIONS RECOGNIZED_LEHMER_RNG_OPTIONS RECOGNIZED_WYHASH_RNG_OPTIONS RECOGNIZED_XOSHIRO_RNG_OPTIONS RECOGNIZED_LCG_RNG_OPTIONS RECOGNIZED_MERSENNE_TWISTER_OPTIONS RECOGNIZED_SUBTRACT_WITH_CARRY_OPTIONS RECOGNIZED_PCG_OPTIONS RECOGNIZED_PCG_CPP_OPTIONS
_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES:=$(foreach rng_option_var, $(_RECOGNIZED_RNG_OPTIONS_VARIABLES), $(firstword $($(rng_option_var))))

# The reason we have to mangle these is that we need these to be single words for the pariwise lookup to work.
# Wildcards would expand to multiple words, and "empty" would be 0 words.
# We expand these later into their actual usable values later (see _normalize_mangled_header defined below)
_RECOGNIZED_RNG_OPTIONS_HEADERS:=
_RECOGNIZED_RNG_OPTIONS_HEADERS+=NO_INSERT # system
_RECOGNIZED_RNG_OPTIONS_HEADERS+=internal/random_headers/lehmer64_cipes.h #lehmer
_RECOGNIZED_RNG_OPTIONS_HEADERS+=internal/random_headers/wyrand_cipes.h #wyhash
_RECOGNIZED_RNG_OPTIONS_HEADERS+=Xoshiro-cpp/XoshiroCpp.hpp # xoshiro
_RECOGNIZED_RNG_OPTIONS_HEADERS+=NO_INSERT # lcg
_RECOGNIZED_RNG_OPTIONS_HEADERS+=NO_INSERT # mersenne_twister
_RECOGNIZED_RNG_OPTIONS_HEADERS+=NO_INSERT # subtract_with_carry
_RECOGNIZED_RNG_OPTIONS_HEADERS+=pcg-c-basic/pcg_basic.h # pcg
_RECOGNIZED_RNG_OPTIONS_HEADERS+=WILDCARD_pcg-cpp/include/*.h # pcg-cpp

_RECOGNIZED_RNG_OPTIONS_NO_INCLUDE=system lcg mersenne_twister subtract_with_carry

_RECOGNIZED_RNG_OPTIONS_NEED_CPP=xoshiro lcg mersenne_twister subtract_with_carry pcg_cpp

_EMPTY:=
_normalize_mangled_header=$(if $(findstring NO_INSERT,$(firstword $1)),$(_EMPTY),$(if $(findstring WILDCARD_,$1),$(wildcard $(1:WILDCARD_)),$1))

_PRINT_RNG_HELP=Available options for RNG_IMPLEMENTATION: $(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES)

ifeq (help,$(RNG_IMPLEMENTATION))
$(info _PRINT_RNG_HELP)
$(error Stopping due to "help" for RNG_IMPLEMENTATION)
endif

-include gmsl

ifeq (T,$(true))
ifeq ($(true),$(call gmsl_compatible,1 1 8))
_HAS_GMSL=1
else
$(warning Incompatible GMSL version, tested against 1.1.8 but current version is $(gmsl_version). Unable to use GMSL, some configuration options will be limited)
_HAS_GMSL=0
endif
else
$(warning No GMSL (Gnu Make Standard Library) found, some configuration options will be limited)
_HAS_GMSL=0
endif

ORIGINAL_RNG_IMPLEMENTATION:=$(RNG_IMPLEMENTATION)
# Process defaults
ifeq (,$(RNG_IMPLEMENTATION))
	RNG_IMPLEMENTATION=default
endif

ifeq ("",$(RNG_IMPLEMENTATION))
	RNG_IMPLEMENTATION=default
endif

ifeq (default,$(RNG_IMPLEMENTATION))
#	ifeq (1,$(IS_WINDOWS))
		RNG_IMPLEMENTATION=lcg
#	else
#		RNG_IMPLEMENTATION=system
#	endif
	_FOUND_RNG_IMPLEMENTATION=$(RNG_IMPLEMENTATION)

else ifeq (1,$(_HAS_GMSL))  # Has GMSL

# The idea behind this is to find which canonical RNG mode the input RNG mode matches.
# Then from there, pariwise match per-RNG-mode properties and configure as needed.

# Populate the mapping from canonical_name -> name_of_variable_with_aliases
_add_to_rng_set=$(call set,_RECOGNIZED_RNG_OPTIONS_MAP,$1,$2)
$(call pairmap,_add_to_rng_set,$(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES),$(_RECOGNIZED_RNG_OPTIONS_VARIABLES))

# Find the first key where $(RNG_IMPLEMENTATION) matches one of the elements of the mapped variable name
_find_str_in_indirect_options=$(filter $1,$($2))

_indirect_lookup=$(call _find_str_in_indirect_options,$1,$(call get,_RECOGNIZED_RNG_OPTIONS_MAP,$2))

_POSSIBLE_MATCHES:=$(foreach key,$(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES),\
  $(if $(call _indirect_lookup,$(RNG_IMPLEMENTATION),$(key)),$(key)))
_FOUND_RNG_IMPLEMENTATION:=$(firstword $(_POSSIBLE_MATCHES))
RNG_IMPLEMENTATION:=$(_FOUND_RNG_IMPLEMENTATION)

# Handle header files
_add_to_rng_headers=$(call set,_RECOGNIZED_RNG_OPTIONS_HEADERS_MAP,$1,$2)
$(call pairmap,_add_to_rng_headers,$(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES),$(_RECOGNIZED_RNG_OPTIONS_VARIABLES))
_RNG_HEADER_MANGLED:=$(call get,_RECOGNIZED_RNG_OPTIONS_HEADERS_MAP,$(RNG_IMPLEMENTATION))

# Verify that those in _RECOGNIZED_RNG_OPTIONS_NO_INCLUDE really are mapped to NO_INSERT
_verify_no_insert=$(call assert,$(filter NO_INSERT,$1))
$(foreach no_include_key,$(_RECOGNIZED_RNG_OPTIONS_NO_INCLUDE),$(call _verify_no_insert,$(call get,_RECOGNIZED_RNG_OPTIONS_HEADERS_MAP,$(no_include_key))))

else # No GSML
$(warning Can't lookup RNG_IMPLEMENTATION values using GMSL - only matching the canonical names, not the aliases)
RNG_IMPLEMENTATION:=$(filter $(RNG_IMPLEMENTATION),$(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES))
ifneq (,$(filter $(RNG_IMPLEMENTATION),$(_RECOGNIZED_RNG_OPTIONS_NO_INCLUDE)))
_RNG_HEADER_MANGLED:=NO_INCLUDE
else
$(warning Can't use automatic deps generation due to unknown header needed for random number selection, from no GMSL. Falling back to rebuilding on any RNG related header change)
RANDOM_HEADERS:=$(foreach raw_header,$(_RECOGNIZED_RNG_OPTIONS_HEADERS),$(call _normalize_mangled_header,$(raw_header)))
endif
endif

ifeq (,$(filter $(_FOUND_RNG_IMPLEMENTATION),$(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES)))
  $(error Invalid value for RNG_IMPLEMENTATION, "$(ORIGINAL_RNG_IMPLEMENTATION)". $(_PRINT_RNG_HELP))
endif

CFLAGS_BASE+=-D_USE_$(RNG_IMPLEMENTATION)_RANDOM=1 -D_RANDOM_IMPL_STR=$(RNG_IMPLEMENTATION)

ifneq (,$(filter $(RNG_IMPLEMENTATION),$(_RECOGNIZED_RNG_OPTIONS_NEED_CPP)))
	NEEDS_CPP=1
	CFLAGS_BASE+=-D_USE_CPP_RANDOM=1
endif

# Flags needed for individual implementations
ifeq (xoshiro,$(RNG_IMPLEMENTATION))
	# Suggested to get vecotorization to work well by https://prng.di.unimi.it/#remarks
	RANDOM_FLAGS+=-fdisable-tree-cunrolli
	ifeq (1,$(USE_LTO))
		_NEED_MULTI_STAGE_FINAL_LINK_FOR_RANDOM=1
	endif
	ifeq (1,$(PERFORMANCE_PROFILING))
		# For consistent profiling results: https://prng.di.unimi.it/#speed
		RANDOM_FLAGS+=-fno-move-loop-invariants -fno-unroll-loops
	endif
else ifeq (pcg,$(RNG_IMPLEMENTATION))
	RANDOM_BASEDIR=pcg-c-basic
	RANDOM_SRCS+=pcg-c-basic/pcg_basic.c
	RANDOM_OBJS+=pcg-c-basic/pcg_basic.o
else ifeq (pcg-cpp,$(RNG_IMPLEMENTATION))
	RANDOM_FLAGS+=-Ipcg-cpp/include
endif

ifeq (1,$(RNG_ALWAYS_USE_32_BIT_CHOICE))
	BASE_CFLAGS+=-D_RNG_ALWAYS_USE_32_BIT_CHOICE=1
endif

ifndef RANDOM_HEADERS
NORMALIZED_RANDOM_HEADERS=$(call _normalize_mangled_header,$(_RNG_HEADER_MANGLED))
endif
ifneq (,NORMALIZED_RANDOM_HEADERS)
RANDOM_HEADERS:=$(NORMALIZED_RANDOM_HEADERS)
endif

# ifeq ($(firstword $(RECOGNIZED_SYSTEM_RNG_OPTIONS)), $(findstring $(RNG_IMPLEMENTATION),$(RECOGNIZED_SYSTEM_RNG_OPTIONS))) 

#MULTILINE=A=a; \
#	echo $${A}
#
#$(info $(MULTILINE))
#$(info $(shell $(MULTILINE)))
#
#IS_WINDOWS_HOST=0
## A crude metric, but it should work unless a user is doing something weird
#ifeq (${OS}, Windows_NT)
#	IS_WINDOWS_HOST=1
#endif
#
##_CURRENT_SHELL=${SHELL}
##ifeq (,$(_CURRENT_SHELL))
##	_ALREADY_IN_SH_LIKE=0
##else
##	_ALREADY_IN_SH_LIKE=1
##endif
##
##ifeq $
##_HAS_SH=$(sh -c "echo hi")
#_HAS_BASH=$(shell bash -c "echo 1")
#_HAS_ZSH=$(shell zsh -c "echo 1")
##ifeq (hi,$(findstring hi,$(HAS_SH) $(HAS_BASH) $(HAS_ZSH)))
##	HAS_SH_LIKE=
#
#
#_SHELL_END=
#
#$(info '_test_a=("a" "b c"); echo $${_test_a[@]} $${#_test_a[@]}')
#_ARRAY_TEST_OUTPUT:=$(shell _test_a=("a" "b c"); echo $${_test_a[@]} $${\#_test_a[@]})
#$(info $(_ARRAY_TEST_OUTPUT))
#ifeq (a b c 2,$(_ARRAY_TEST_OUTPUT))
#	_SHELL_SUPPORTS_ARRAY_SYNTAX=1
#else
#ifeq (Darwin 1,$(shell uname) $(_HAS_ZSH))
#	_SHELL_PREFIX:=$(shell which zsh) -c '
#else ifeq (1,$(_HAS_BASH))
#	_SHELL_PREFIX :=$(shell which bash) -c '
#else ifeq (1,$(_HAS_ZSH))
#	_SHELL_PREFIX :=$(shell which zsh) -c '
#endif
#$(info $(_SHELL_PREFIX))
#ifneq (,$(_SHELL_PREFIX))
#_SHELL_END:='
#$(info $(_SHELL_END))
#$(info $(_SHELL_PREFIX) _test_a=("a" "b c"); echo $${_test_a[@]} $${#_test_a[@]} $(_SHELL_END))
#_ARRAY_TEST_OUTPUT:=$(shell $(_SHELL_PREFIX) _test_a=("a" "b c"); echo $${_test_a[@]} $${\#_test_a[@]} $(_SHELL_END))
#$(info $(_ARRAY_TEST_OUTPUT))
#endif
#ifeq (a b c 2,$(_ARRAY_TEST_OUTPUT))
#	_SHELL_SUPPORTS_ARRAY_SYNTAX=1
#else
#$(warning The current shell does not support array variables. Can't lookup RNG_IMPLEMENTATION values using aliases - only matching canonical names)
#_SHELL_SUPPORTS_ARRAY_SYNTAX=0
#endif
#endif
#
#quote_surround="$(1)"
#
#def_sh_var=$(1)=($($(1)))
#
#ifeq (1,$(_SHELL_SUPPORTS_ARRAY_SYNTAX))
#_MATCHED_RNG_OPTION_COMMAND=_RNG_CANONICAL_NAMES=($(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES)); \
#_RNG_OPTIONS_VARIABLES=($(_RECOGNIZED_RNG_OPTIONS_VARIABLES)); \
#_TO_MATCH="$(RNG_IMPLEMENTATION)"; \
#$(foreach v,$(_RECOGNIZED_RNG_OPTIONS_VARIABLES),$(call def_sh_var,$v);) \
#is_in_arr() { \
#  local search_str="$${1}"; local arr_name="$${2}"; \
#  for s in eval "echo \$${$$2[@]}"; do \
#    if [ "$$search_str" = "$$s" ]; then return 0; fi; \
#  done; \
#  return 1 \
#}; \
#for i in $$(seq 0 $${\\\#_RNG_CANONICAL_NAMES[@]}); do \
#  if is_in_arr "$$_TO_MATCH" "$${_RECOGNIZED_RNG_OPTIONS_VARIABLES[@]}"; then \
#    echo "$${_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES[$$i]}"; \
#    _FOUND="1"; \
#    break; \
#  fi; \
#  if [ "$${_FOUND}" != "1" ]; then \
#  	echo "unrecognized"; \
#  	false; \
#  else \
#    true; \
#  fi; \
#done
#$(info $(_MATCHED_RNG_OPTION_COMMAND))
#_MATCHED_RNG_OPTION=$(shell $(_SHELL_PREFIX) $(_MATCHED_RNG_OPTION_COMMAND) $(_SHELL_END))
#else
#_MATCHED_RNG_OPTION=$(findstring $(RNG_IMPLEMENTATION),$(_RECOGNIZED_RNG_OPTIONS_CANONICAL_NAMES))
#endif
#
#$(info $(_MATCHED_RNG_OPTION))
#$(info $(_MATCHED_RNG_OPTION_COMMAND))