Drop mswin support of MJIT (#6265)

The current MJIT relies on SIGCHLD and fork(2) to be performant, and
it's something mswin can't offer. You could run Linux MJIT on WSL
instead.

[Misc #18968]

3 files changed, 1 insertions, 123 deletions

diff --git a/win32/Makefile.sub b/win32/Makefile.sub
index bea24450ed..1aa27a9119 100644
--- a/win32/Makefile.sub
+++ b/win32/Makefile.sub
@@ -319,33 +319,7 @@ CPPFLAGS = $(DEFS) $(ARCHDEFS) $(CPPFLAGS)
 CPPFLAGS = -DDISABLE_RUBYGEMS $(CPPFLAGS)
 !endif
 !ifndef MJIT_SUPPORT
-MJIT_SUPPORT = yes
-!endif
-!if "$(CPPOUTFLAG)" == ">"
-MJIT_HEADER_FLAGS =
-!else
-MJIT_HEADER_FLAGS = -P
-!endif
-MJIT_HEADER_SUFFIX =
-MJIT_HEADER_ARCH =
-MJIT_HEADER_INSTALL_DIR = include/$(RUBY_VERSION_NAME)/$(arch)
-MJIT_PRECOMPILED_HEADER_NAME = rb_mjit_header-$(RUBY_PROGRAM_VERSION).pch
-MJIT_PRECOMPILED_HEADER = $(MJIT_HEADER_INSTALL_DIR)/$(MJIT_PRECOMPILED_HEADER_NAME)
-!ifndef MJIT_CC
-MJIT_CC = $(CC)
-!endif
-!ifndef MJIT_OPTFLAGS
-# TODO: Use only $(OPTFLAGS) for performance. It requires to modify flags for precompiled header too.
-# For now, using flags used for building precompiled header to make JIT succeed.
-MJIT_OPTFLAGS = -DMJIT_HEADER $(CFLAGS) $(XCFLAGS) $(CPPFLAGS)
-!endif
-!ifndef MJIT_DEBUGFLAGS
-# TODO: Make this work... Another header for debug build needs to be installed first.
-MJIT_DEBUGFLAGS = $(empty) $(DEBUGFLAGS) $(empty)
-MJIT_DEBUGFLAGS = $(MJIT_DEBUGFLAGS: -Zi = -Z7 )
-!endif
-!ifndef MJIT_LDSHARED
-MJIT_LDSHARED = $(MJIT_CC) -LD
+MJIT_SUPPORT = no
 !endif
 
 POSTLINK =
@@ -918,11 +892,7 @@ $(CONFIG_H): $(MKFILES) $(srcdir)/win32/Makefile.sub $(win_srcdir)/Makefile.sub
 #define RUBY_COREDLL "$(RT)"
 #define RUBY_PLATFORM "$(arch)"
 #define RUBY_SITEARCH "$(sitearch)"
-!if "$(MJIT_SUPPORT)" == "yes"
-#define USE_MJIT 1
-!else
 #define USE_MJIT 0
-!endif
 #endif /* $(guard) */
 <<
 
@@ -1338,42 +1308,6 @@ probes.h: {$(VPATH)}probes.dmyh
 #include "$(*F).dmyh"
 <<KEEP
 
-main: mjit-headers
-yes-mjit-headers: $(MJIT_PRECOMPILED_HEADER)
-clean-local::
-	$(Q)$(RM) $(MJIT_PRECOMPILED_HEADER_NAME) $(MJIT_PRECOMPILED_HEADER_NAME:.pch=.)$(OBJEXT)
-	$(Q)$(RM) $(TIMESTAMPDIR)/$(MJIT_PRECOMPILED_HEADER_NAME:.pch=.time) mjit_config.h
-	$(Q)$(RM) $(MJIT_HEADER_INSTALL_DIR)/rb_mjit_header-*.pch
-	$(Q)$(RM) $(MJIT_HEADER_INSTALL_DIR)/rb_mjit_header-*.$(OBJEXT)
-	-$(Q) $(RMDIRS) $(MJIT_HEADER_INSTALL_DIR) 2> $(NULL) || exit 0
-	$(Q)$(RM) $(arch_hdrdir)/rb_mjit_header-*.pch
-	$(Q)$(RM) $(arch_hdrdir)/rb_mjit_header-*.$(OBJEXT)
-
-# Non-mswin environment is not using prebuilt precompiled header because upgrading compiler
-# or changing compiler options may break MJIT so build (currently only by --mjit-debug though).
-#
-# But mswin is building precompiled header because cl.exe cannot leave macro after preprocess.
-# As a workaround to use macro without installing many source files, it uses precompiled header
-# without sufficient guard for a broken build.
-#
-# TODO: Fix the above issue by including VC version in header name, and create another header
-# for --mjit-debug as well.
-$(TIMESTAMPDIR)/$(MJIT_PRECOMPILED_HEADER_NAME:.pch=).time: probes.h vm.$(OBJEXT)
-	$(ECHO) building $(@F:.time=.pch)
-	$(Q) $(CC) -DMJIT_HEADER $(CFLAGS: -Zi = -Z7 ) $(XCFLAGS:-DRUBY_EXPORT =) -URUBY_EXPORT $(CPPFLAGS) $(srcdir)/vm.c -c -Yc \
-	  $(COUTFLAG)$(@F:.time=.)$(OBJEXT) -Fd$(@F:.time=.pdb) -Fp$(@F:.time=.pch).new -Z7
-	$(Q) $(IFCHANGE) "--timestamp=$@" $(@F:.time=.pch) $(@F:.time=.pch).new
-
-$(MJIT_PRECOMPILED_HEADER_NAME): $(TIMESTAMPDIR)/$(MJIT_PRECOMPILED_HEADER_NAME:.pch=).time
-
-$(MJIT_PRECOMPILED_HEADER): $(MJIT_PRECOMPILED_HEADER_NAME)
-	$(Q) $(MAKEDIRS) $(MJIT_HEADER_INSTALL_DIR)
-	$(Q) $(MAKE_LINK) $(MJIT_PRECOMPILED_HEADER_NAME) $@
-	$(Q) $(MAKE_LINK) $(MJIT_PRECOMPILED_HEADER_NAME:.pch=.)$(OBJEXT) $(MJIT_HEADER_INSTALL_DIR)/$(MJIT_PRECOMPILED_HEADER_NAME:.pch=.)$(OBJEXT)
-	$(Q) $(MAKEDIRS) $(arch_hdrdir)
-	$(Q) $(MAKE_LINK) $(MJIT_PRECOMPILED_HEADER_NAME) $(arch_hdrdir)/$(MJIT_PRECOMPILED_HEADER_NAME)
-	$(Q) $(MAKE_LINK) $(MJIT_PRECOMPILED_HEADER_NAME:.pch=.)$(OBJEXT) $(arch_hdrdir)/$(MJIT_PRECOMPILED_HEADER_NAME:.pch=.)$(OBJEXT)
-
 INSNS	= opt_sc.inc optinsn.inc optunifs.inc insns.inc insns_info.inc \
 	  vmtc.inc vm.inc mjit_compile.inc
 
@@ -1399,46 +1333,3 @@ loadpath: verconf.h
 	@$(CPP) $(XCFLAGS) $(CPPFLAGS) $(srcdir)/loadpath.c | \
 	sed -e '1,/^const char ruby_initial_load_paths/d;/;/,$$d' \
 	    -e '/^^ /!d;s/ *"\\\\0"$$//;s/" *"//g'
-
-mjit_config.h: $(MKFILES) $(srcdir)/win32/Makefile.sub $(win_srcdir)/Makefile.sub
-	@echo making <<$@
-#ifndef RUBY_MJIT_CONFIG_H
-#define RUBY_MJIT_CONFIG_H 1
-
-#define MJIT_CONFIG_ESCAPED_EQ "="
-#define MJIT_HEADER_INSTALL_DIR "/$(MJIT_HEADER_INSTALL_DIR)"
-#define MJIT_MIN_HEADER_NAME "$(MJIT_MIN_HEADER_NAME)"
-#define MJIT_PRECOMPILED_HEADER_NAME "$(MJIT_PRECOMPILED_HEADER_NAME)"
-<<KEEP
-	@
-	@(set sep=#define MJIT_CC_COMMON ) & \
-	for %I in ($(MJIT_CC)) do @(call echo.%%sep%%"%%~I", \& set sep= ) >> $@
-	@echo /* MJIT_CC_COMMON */>> $@
-	@
-	@(set sep=#define MJIT_CFLAGS ) & \
-	for %I in ($(RUNTIMEFLAG) $(ARCH_FLAG)) do @(call echo.%%sep%%"%%~I", \& set sep= ) >> $@
-	@echo /* MJIT_CFLAGS */>> $@
-	@
-	@(set sep=#define MJIT_OPTFLAGS ) & \
-	for %I in ($(MJIT_OPTFLAGS:^==" MJIT_CONFIG_ESCAPED_EQ ")) do @(call echo.%%sep%%"%%~I", \& set sep= ) >> $@
-	@echo /* MJIT_OPTFLAGS */>> $@
-	@
-	@(set sep=#define MJIT_DEBUGFLAGS ) & \
-	for %I in ($(MJIT_DEBUGFLAGS:^==" MJIT_CONFIG_ESCAPED_EQ ")) do @(call echo.%%sep%%"%%~I", \& set sep= ) >> $@
-	@echo /* MJIT_DEBUGFLAGS */>> $@
-	@
-	@(set sep=#define MJIT_LDSHARED ) & \
-	for %I in ($(MJIT_LDSHARED)) do @(call echo.%%sep%%"%%~I", \& set sep= ) >> $@
-	@echo /* MJIT_LDSHARED */>> $@
-	@
-	@(set sep=#define MJIT_DLDFLAGS ) & \
-	for %I in ($(DLDFLAGS)) do @(call echo.%%sep%%"%%~I", \& set sep= ) >> $@
-	@echo /* MJIT_DLDFLAGS */>> $@
-	@
-	@(set sep=#define MJIT_LIBS ) & \
-	for %I in ($(LIBRUBYARG_SHARED)) do @(call echo.%%sep%%"%%~I", \& set sep= ) >> $@
-	@echo /* MJIT_LIBS */>> $@
-	@
-	@echo.>> $@
-	@echo #endif /* RUBY_MJIT_CONFIG_H */>> $@
-	@$(Q:@=: :) type $@
diff --git a/win32/configure.bat b/win32/configure.bat
index 4602b41ec5..a3df0bb4eb 100755
--- a/win32/configure.bat
+++ b/win32/configure.bat
@@ -38,8 +38,6 @@ if "%1" == "--enable-devel" goto :enable-devel
 if "%1" == "--disable-devel" goto :disable-devel

 if "%1" == "--enable-rubygems" goto :enable-rubygems

 if "%1" == "--disable-rubygems" goto :disable-rubygems

-if "%1" == "--enable-mjit-support" goto :enable-mjit-support

-if "%1" == "--disable-mjit-support" goto :disable-mjit-support

 if "%1" == "--extout" goto :extout

 if "%1" == "--path" goto :path

 if "%1" == "--with-baseruby" goto :baseruby

@@ -165,16 +163,6 @@ goto :loop ;
   echo>>confargs.tmp  %1 \

   shift

 goto :loop ;

-:enable-mjit-support

-  echo>> ~tmp~.mak 	"MJIT_SUPPORT=yes" \

-  echo>>confargs.tmp  %1 \

-  shift

-goto :loop ;

-:disable-mjit-support

-  echo>> ~tmp~.mak 	"MJIT_SUPPORT=no" \

-  echo>>confargs.tmp  %1 \

-  shift

-goto :loop ;

 :ntver

   echo>> ~tmp~.mak 	"NTVER=%~2" \

   echo>>confargs.tmp  %1=%2 \

diff --git a/win32/setup.mak b/win32/setup.mak
index fd804a84ce..17e321b984 100644
--- a/win32/setup.mak
+++ b/win32/setup.mak
@@ -295,7 +295,6 @@ AS = $(AS) -nologo
 	(echo AS = $(AS:64=) -nologo) || \
 	(echo AS = $(AS) -nologo) ) >>$(MAKEFILE)
 !endif
-	@(for %I in (cl.exe) do @set MJIT_CC=%~$$PATH:I) && (call echo MJIT_CC = "%MJIT_CC:\=/%" -nologo>>$(MAKEFILE))
 	@type << >>$(MAKEFILE)
 
 $(BANG)include $$(srcdir)/win32/Makefile.sub