8007446: Add /MP to cl.exe speeds up windows builds of OpenJDK.

Reviewed-by: sla, ctornqvi

make/windows/makefiles/compile.make

@@ -44,6 +44,7 @@ CXX=cl.exe
 #   /GS       Inserts security stack checks in some functions (VS2005 default)
 #   /Oi       Use intrinsics (in /O2)
 #   /Od       Disable all optimizations
+#   /MP       Use multiple cores for compilation
 #
 # NOTE: Normally following any of the above with a '-' will turn off that flag
 #
@@ -206,6 +207,7 @@ FASTDEBUG_OPT_OPTION = /O2 /Oy-
 DEBUG_OPT_OPTION     = /Od
 GX_OPTION = /EHsc
 LD_FLAGS = /manifest $(LD_FLAGS)
+MP_FLAG = /MP
 # Manifest Tool - used in VS2005 and later to adjust manifests stored
 # as resources inside build artifacts.
 !if "x$(MT)" == "x"
@@ -219,6 +221,7 @@ FASTDEBUG_OPT_OPTION = /O2 /Oy-
 DEBUG_OPT_OPTION     = /Od
 GX_OPTION = /EHsc
 LD_FLAGS = /manifest $(LD_FLAGS)
+MP_FLAG = /MP
 # Manifest Tool - used in VS2005 and later to adjust manifests stored
 # as resources inside build artifacts.
 !if "x$(MT)" == "x"
@@ -235,6 +238,7 @@ FASTDEBUG_OPT_OPTION = /O2 /Oy-
 DEBUG_OPT_OPTION     = /Od
 GX_OPTION = /EHsc
 LD_FLAGS = /manifest $(LD_FLAGS)
+MP_FLAG = /MP
 # Manifest Tool - used in VS2005 and later to adjust manifests stored
 # as resources inside build artifacts.
 !if "x$(MT)" == "x"
@@ -245,6 +249,8 @@ LD_FLAGS = /SAFESEH $(LD_FLAGS)
 !endif
 !endif
 
+CXX_FLAGS = $(CXX_FLAGS) $(MP_FLAG)
+
 # If NO_OPTIMIZATIONS is defined in the environment, turn everything off
 !ifdef NO_OPTIMIZATIONS
 PRODUCT_OPT_OPTION   = $(DEBUG_OPT_OPTION)

make/windows/makefiles/sa.make

@@ -108,6 +108,8 @@ SA_LFLAGS = $(SA_LD_FLAGS) -nologo -subsystem:console -machine:$(MACHINE)
 SA_LFLAGS = $(SA_LFLAGS) -map -debug
 !endif
 
+SA_CFLAGS = $(SA_CFLAGS) $(MP_FLAG)
+
 # Note that we do not keep sawindbj.obj around as it would then
 # get included in the dumpbin command in build_vm_def.sh