test

Linker and Libraries Guide

x64: Local Executable (LE)

This code sequence implements the LE model described in Thread-Local Storage Access Models.

Table 8–22 x64: Local Executable Thread-Local Variable Access Codes

Code Sequence

Initial Relocations

Symbol 

0x00 movq %fs:0, %rax
0x06 leaq  x@tpoff(%rax), %rax

# %rax - contains address of TLS variable
 
<none>
R_AMD64_TPOFF32
 
x

To load the contents of a TLS variable instead of the address of a TLS variable, the following sequence can be used.

Table 8–23 x64: Local Executable Thread-Local Variable Access Codes II

Code Sequence

Initial Relocations

Symbol 

0x00 movq %fs:0, %rax
0x06 movq  x@tpoff(%rax), %rax

# %rax - contains contents of TLS variable
 
<none>
R_AMD64_TPOFF32
 
x

The following sequence is even shorter.

Table 8–24 x64: Local Executable Thread-Local Variable Access Codes III

Code Sequence

Initial Relocations

Symbol 

0x00 movq  %fs:x@tpoff, %rax

# %rax - contains contents of TLS variable
 
R_AMD64_TPOFF32
 
x