Add big integer implementation

CMakeLists.txt

@@ -12,6 +12,7 @@ include(CheckSymbolExists)
 
 # Project settings
 option(BH_PLATFORM_THREADS "Enable multithreading support" TRUE)
+option(BH_BIGINT_LONG "Use bigger internal units for big integer calculations" TRUE)
 
 # Check for IPO/LTO
 check_ipo_supported(RESULT supported)
@@ -34,6 +35,7 @@ set(BH_SOURCE
     src/thread.c
     src/io.c
     src/deflate.c
+    src/bigint.c
 )
 
 set(BH_HEADER
@@ -46,6 +48,7 @@ set(BH_HEADER
     include/bh/thread.h
     include/bh/io.h
     include/bh/deflate.h
+    include/bh/bigint.h
 )
 
 set(BH_INCLUDE_DIRS