- fix float to double implicit conversion
- add isnanf and signbitf macros, map them to existing double version when float versions are absent
- enable -Wdouble-promotion by default
- define isnan as macro for platform use core\sahred\platform\common\math.c
And enable classic interpreter instead fast interpreter when llvm jit is enabled,
so as to fix the issue that llvm jit cannot handle opcode drop_64/select_64.
Implement XIP (Execution In Place) feature for AOT mode to enable running the AOT code inside AOT file directly, without memory mapping the executable memory for AOT code and applying relocations for text section. Developer can use wamrc with "--enable-indirect-mode --disable-llvm-intrinsics" flags to generate the AOT file and run iwasm with "--xip" flag. Known issues: there might still be some relocations in the text section which access the ".rodata" like sections.
And also enable ARC target support for both interpreter mode and AOT mode.
Signed-off-by: Wenyong Huang <wenyong.huang@intel.com>
