Support i386 option for absolute baseline x86 support

Make.inc

@@ -42,7 +42,7 @@ USE_INTEL_JITEVENTS = 0
 USE_LIBCPP = 0
 
 # Select the cpu architecture to target
-# Current available options are "native" and "core2"
+# Current available options are "native", "core2" and "i386"
 JULIA_CPU_TARGET = native
 
 # we include twice to pickup user definitions better
@@ -266,6 +266,8 @@ ifeq ($(JULIA_CPU_TARGET),native)
  JCPPFLAGS += -DJULIA_TARGET_NATIVE
 else ifeq ($(JULIA_CPU_TARGET),core2)
  JCPPFLAGS += -DJULIA_TARGET_CORE2
+else ifeq ($(JULIA_CPU_TARGET),i386)
+ JCPPFLAGS += -DJULIA_TARGET_I386
 else
  $(error Unknown cpu target architecture)
 endif

src/codegen.cpp

@@ -451,6 +451,8 @@ static Type *NoopType;
 extern "C" {
 #if defined(JULIA_TARGET_CORE2)
 const char *jl_cpu_string = "core2";
+#elif defined(JULIA_TARGET_I386)
+const char *jl_cpu_string = "i386";
 #elif defined(JULIA_TARGET_NATIVE)
 const char *jl_cpu_string = "native";
 #else

src/dump.c

@@ -132,7 +132,7 @@ static void jl_load_sysimg_so(char *fname)
  jl_error("The current host does not support SSSE3, but the system image was compiled for Core2.\n"
  "Please delete or regenerate sys.{so,dll,dylib}.");
  }
- else {
+ else if(strcmp(cpu_target,"i386") != 0) {
  jl_error("System image has unknown target cpu architecture.\n"
  "Please delete or regenerate sys.{so,dll,dylib}.");
  }