x64 machine code generation (ELF)

vlib/compiler/x64/elf_obj.v

@@ -0,0 +1,161 @@
+// Copyright (c) 2019 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+
+module x64
+
+/*
+This file is unused right now, since binaries without sections
+are generated.
+
+But it will be necessary once we have dynamic linking.
+*/
+
+enum SectionType {
+	null = 0
+	progbits = 1
+	symtab = 2
+	strtab = 3
+	rela = 4
+}	
+
+struct SectionConfig {
+	name string
+	typ SectionType
+	flags i64
+	data voidptr
+	is_saa bool
+	datalen i64
+	link int
+	info int
+	align i64
+	entsize i64
+}	
+
+fn (g mut Gen) section_header(c SectionConfig) {
+	g.write32(g.sect_header_name_pos)
+	g.sect_header_name_pos += c.name.len + 1
+	g.write32(int(c.typ))
+	g.write64(c.flags)
+	g.write64(0) // sh_addr
+	g.write64(g.offset)// offset
+	g.offset += c.datalen+1
+	g.write64(c.datalen)
+	g.write32(c.link)
+	g.write32(c.info)
+	g.write64(c.align)
+	g.write64(c.entsize)
+}	
+
+
+fn genobj() {
+	/*
+	// SHN_UNDEF
+	mut g := Gen{}
+	nr_sections := 7
+	g.section_header(SectionConfig{
+		name: ''
+		typ: .null
+		flags:0
+		data: 0
+		is_saa: false
+		link: 0
+		info:0
+		align:0
+		entsize: 0
+	})
+	
+		/*
+	for sect in sections {
+		g.section_header(SectionConfig{
+			name:0
+			typ: sect.typ
+			flags: sect.flags
+			data: sect.data
+			is_saa: true
+			datalen: sect.len
+			link: 0
+			info: 0
+			align: sect.align
+			entsize: sect.entsize
+		})
+		
+	}	
+	*/
+	
+	g.section_header(SectionConfig{
+		name: '.DATA'
+		typ: .progbits
+		flags: 0x2
+		//data: sect.data
+		is_saa: true
+		datalen: 0xd
+		link: 0
+		info: 0
+		align: 1
+		entsize: 0
+	})
+	
+	g.section_header(SectionConfig{
+		name: '.TEXT'
+		typ: .progbits
+		flags: 0x2
+		//data: sect.data
+		is_saa: true
+		datalen: 0xd
+		link: 0
+		info: 0
+		align: 1
+		entsize: 0
+	})
+	g.section_header(SectionConfig{
+		name: '.shstrtab'
+		typ: .strtab
+		flags: 0x2
+		//data: sect.data
+		is_saa: true
+		datalen: 0x22
+		link: 0
+		info: 0
+		align: 1
+		entsize: 0
+	})
+	g.section_header(SectionConfig{
+		name: '.symtab'
+		typ: .symtab
+		flags: 0x2
+		//data: sect.data
+		is_saa: true
+		datalen: 0xd
+		link: 0
+		info: 0
+		align: 1
+		entsize: 0
+	})
+	g.section_header(SectionConfig{
+		name: '.strtab'
+		typ: .symtab
+		flags: 0x2
+		//data: sect.data
+		is_saa: true
+		datalen: 0xd
+		link: 0
+		info: 0
+		align: 1
+		entsize: 0
+	})
+	g.section_header(SectionConfig{
+		name: '.rela.TEXT'
+		typ: .rela
+		flags: 0x0
+		//data: sect.data
+		is_saa: true
+		datalen: 0x18
+		link: 4
+		info: 2
+		align: 8
+		entsize: 0x18
+	})
+	*/
+}
+