[PATCH] OSX: Mach-O object file output
- From: Adam Strzelecki <ono@xxxxxxx>
- To: luajit@xxxxxxxxxxxxx
- Date: Sat, 3 Nov 2012 20:12:18 +0100
Supported architectures: x86, x64, arm
Selecting arm, produces FAT object file for: armv6, armv7, armv7s & x86
(simulator).
---
src/jit/bcsave.lua | 155 +++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 154 insertions(+), 1 deletion(-)
diff --git a/src/jit/bcsave.lua b/src/jit/bcsave.lua
index bf69e00..6f32c29 100644
--- a/src/jit/bcsave.lua
+++ b/src/jit/bcsave.lua
@@ -398,7 +398,160 @@ typedef struct {
end
local function bcsave_machobj(ctx, output, s, ffi)
- check(false, "NYI: no support for writing OSX object files")
+ check(({ x86=true, x64=true, arm=true })[ctx.arch], "only x86, x64 and arm
architectures are allowed for osx")
+ ffi.cdef[[
+typedef struct
+{
+ uint32_t magic, cputype, cpusubtype, filetype, ncmds, sizeofcmds, flags;
+} mach_header;
+typedef struct
+{
+ uint32_t magic, cputype, cpusubtype, filetype, ncmds, sizeofcmds, flags,
reserved;
+} mach_header_64;
+typedef struct {
+ uint32_t cmd, cmdsize;
+ char segname[16];
+ uint32_t vmaddr, vmsize, fileoff, filesize;
+ uint32_t maxprot, initprot, nsects, flags;
+} mach_segment_command;
+typedef struct {
+ uint32_t cmd, cmdsize;
+ char segname[16];
+ uint64_t vmaddr, vmsize, fileoff, filesize;
+ uint32_t maxprot, initprot, nsects, flags;
+} mach_segment_command_64;
+typedef struct {
+ char sectname[16], segname[16];
+ uint32_t addr, size;
+ uint32_t offset, align, reloff, nreloc, flags, reserved1, reserved2;
+} mach_section;
+typedef struct {
+ char sectname[16], segname[16];
+ uint64_t addr, size;
+ uint32_t offset, align, reloff, nreloc, flags, reserved1, reserved2,
reserved3;
+} mach_section_64;
+typedef struct {
+ uint32_t cmd, cmdsize, symoff, nsyms, stroff, strsize;
+} mach_symtab_command;
+typedef struct {
+ int32_t strx;
+ uint8_t type, sect;
+ int16_t desc;
+ uint32_t value;
+} mach_nlist;
+typedef struct {
+ uint32_t strx;
+ uint8_t type, sect;
+ uint16_t desc;
+ uint64_t value;
+} mach_nlist_64;
+typedef struct
+{
+ uint32_t magic, nfat_arch;
+} mach_fat_header;
+typedef struct
+{
+ uint32_t cputype, cpusubtype, offset, size, align;
+} mach_fat_arch;
+typedef struct {
+ struct {
+ mach_header hdr;
+ mach_segment_command seg;
+ mach_section sec;
+ mach_symtab_command sym;
+ } arch[1];
+ mach_nlist sym_entry;
+ uint8_t space[4096];
+} mach_obj;
+typedef struct {
+ struct {
+ mach_header_64 hdr;
+ mach_segment_command_64 seg;
+ mach_section_64 sec;
+ mach_symtab_command sym;
+ } arch[1];
+ mach_nlist_64 sym_entry;
+ uint8_t space[4096];
+} mach_obj_64;
+typedef struct {
+ mach_fat_header fat;
+ mach_fat_arch fat_arch[4];
+ struct {
+ mach_header hdr;
+ mach_segment_command seg;
+ mach_section sec;
+ mach_symtab_command sym;
+ } arch[4];
+ mach_nlist sym_entry;
+ uint8_t space[4096];
+} mach_fat_obj;
+]]
+ local symname = '_'..LJBC_PREFIX..ctx.modname
+ local is64, align = false, 4
+ local isfat = (ctx.arch == "arm")
+ if ctx.arch == "x64" then
+ is64 = true
+ align = 8
+ end
+ local function aligned(v,a) return v + (a - (v % a)) % a end
+ -- Assuming we are running on LE machine.
+ local be32 = bit.bswap
+
+ -- Create Mach-O object and fill in header.
+ local o = ffi.new(({ x86="mach_obj", x64="mach_obj_64", arm="mach_fat_obj"
})[ctx.arch])
+ local mach_size = aligned(ffi.offsetof(o, "space")+#symname+2, align)
+ local cputype = ({ x86={7}, x64={0x01000007}, arm={7,12,12,12}
})[ctx.arch]
+ local cpusubtype = ({ x86={3}, x64={3}, arm={3, 6, 9,11}
})[ctx.arch]
+ if isfat then
+ o.fat.magic = be32(0xcafebabe)
+ o.fat.nfat_arch = be32(#cpusubtype)
+ end
+ for i = 0, #cpusubtype-1 do
+ local offset = 0
+ if isfat then
+ local a = o.fat_arch[i]
+ a.cputype = be32(cputype[i+1])
+ a.cpusubtype = be32(cpusubtype[i+1])
+ -- Subsequent slices overlap each other to share data.
+ offset = ffi.sizeof(o.fat) + ffi.sizeof(o.fat_arch) +
i*ffi.sizeof(o.arch[0])
+ a.offset = be32(offset)
+ a.size = be32(mach_size-offset+#s)
+ end
+ local a = o.arch[i]
+ a.hdr.magic = is64 and 0xfeedfacf or 0xfeedface
+ a.hdr.cputype = cputype[i+1]
+ a.hdr.cpusubtype = cpusubtype[i+1]
+ a.hdr.filetype = 0x1 -- obj
+ a.hdr.ncmds = 2
+ a.hdr.sizeofcmds = ffi.sizeof(a.seg)+ffi.sizeof(a.sec)+ffi.sizeof(a.sym)
+ a.seg.cmd = is64 and 0x19 or 0x1 -- segment
+ a.seg.cmdsize = ffi.sizeof(a.seg)+ffi.sizeof(a.sec)
+ a.seg.vmsize = #s
+ a.seg.fileoff = mach_size-offset
+ a.seg.filesize = #s
+ a.seg.maxprot = 0x1 -- readonly
+ a.seg.initprot = 0x1
+ a.seg.nsects = 1
+ ffi.copy(a.sec.sectname, "__data")
+ ffi.copy(a.sec.segname, "__DATA")
+ a.sec.size = #s
+ a.sec.offset = mach_size-offset
+ a.sym.cmd = 0x2 -- symbol table
+ a.sym.cmdsize = ffi.sizeof(a.sym)
+ a.sym.symoff = ffi.offsetof(o, "sym_entry")-offset
+ a.sym.nsyms = 1
+ a.sym.stroff = ffi.offsetof(o,
"sym_entry")+ffi.sizeof(o.sym_entry)-offset
+ a.sym.strsize = aligned(#symname+2, align)
+ end
+ o.sym_entry.type = 0xf
+ o.sym_entry.sect = 1
+ o.sym_entry.strx = 1
+ ffi.copy(o.space+1, symname)
+
+ -- Write Macho-O object file.
+ local fp = savefile(output, "wb")
+ fp:write(ffi.string(o, mach_size))
+ bcsave_tail(fp, output, s)
end
local function bcsave_obj(ctx, output, s)
--
1.7.10.2 (Apple Git-33)
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