#include "macros.h"

#if GNU_ASSEMBLER
#define ASM_TYPE(NAME, TYPE) .type NAME, TYPE
#define ASM_END(NAME) .size NAME, .- NAME
#else
#define ASM_TYPE(NAME, TYPE)
#define ASM_END(NAME)
#endif

#define ASM_GLOBAL(NAME, TYPE)                                                                                         \
	.globl SYMBOL_NAME(NAME);                                                                                          \
	ASM_TYPE(SYMBOL_NAME(NAME), TYPE);                                                                                 \
	SYMBOL_NAME(NAME) :
#if GNU_ASSEMBLER
#define ASM_WEAK(NAME, TYPE)                                                                                           \
	.weak SYMBOL_NAME(NAME);                                                                                           \
	ASM_TYPE(SYMBOL_NAME(NAME), TYPE);                                                                                 \
	SYMBOL_NAME(NAME) :
#else
#define ASM_WEAK(NAME, TYPE)                                                                                           \
	.globl SYMBOL_NAME(NAME);                                                                                          \
	.weak_definition SYMBOL_NAME(NAME);                                                                                \
	ASM_TYPE(SYMBOL_NAME(NAME), TYPE)                                                                                  \
	SYMBOL_NAME(NAME) :
#endif

#ifdef __linux__
.section .note.GNU-stack, "", @progbits
#endif

.intel_syntax noprefix

#ifdef __x86_64__

.macro LJMP32 teb_reg
#ifdef __APPLE__
#define m1632 m1632_\@
.data
m1632:
    .long 1f             # 32-bit code offset
    .long 0              # 32-bit code segment (filled in at runtime)
.text
    mov r10w, word ptr [\teb_reg+TEB_FS_SEL]
    sub r10w, 16
    mov word ptr [rip+m1632+4], r10w
    jmp fword ptr [rip+m1632]
#else
	jmp fword ptr [rip] # far jump into 32-bit code
    .long 1f            # 32-bit code offset
    .word CS_32         # 32-bit code segment
#endif
.code32
1:
    endbr32
.endm

.macro LJMP64 teb_reg
// Annoyingly, we can't assemble this in Intel syntax
.att_syntax prefix
    ljmp $CS_64, $1f
.intel_syntax noprefix
.code64
1:
    endbr64
.endm

#endif // __x86_64__

.macro GET_TEB_HOST reg

#if defined(__APPLE__) && defined(__x86_64__)
// TLS slot 6 reserved for Win64 compatibility
// https://github.com/apple/darwin-libpthread/blob/03c4628c8940cca6fd6a82957f683af804f62e7f/private/tsd_private.h#L92-L97
mov \reg, gs:[0x30]
#elif defined(__linux__) && defined(__x86_64__)
mov \reg, fs:[currentThreadTeb@tpoff]
#elif defined(__linux__) && defined(__i386__)
mov \reg, gs:[currentThreadTeb@ntpoff]
#else
#error "Unsupported platform"
#endif

.endm