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Chapter 11. Alpha Dependent Features

!samegp

Used with any branch format instruction to skip the GP load at the target address. The referenced

symbol must have the same GP as the source object file, and it must be declared to either not use

$27

or perform a standard GP load in the first two instructions via the

.prologue

directive.

!tlsgd

!tlsgd!N

Used with an

lda

instruction to load the address of a TLS descriptor for a symbol in the GOT.

The sequence number

N

is optional, and if present it used to pair the descriptor load with both

the

literal

loading the address of the

__tls_get_addr

function and the

lituse_tlsgd

marking the call to that function.

For proper relaxation, both the

tlsgd

,

literal

and

lituse

relocations must be in the same

extended basic block. That is, the relocation with the lowest address must be executed first at

runtime.

!tlsldm

!tlsldm!N

Used with an

lda

instruction to load the address of a TLS descriptor for the current module in

the GOT.

Similar in other respects to

tlsgd

.

!gotdtprel

Used with an

ldq

instruction to load the offset of the TLS symbol within its module's thread 

local storage block. Also known as the dynamic thread pointer offset or dtp relative offset.

!dtprelhi

!dtprello

!dtprel

Like

gprel

relocations except they compute dtp relative offsets.

!gottprel

Used with an

ldq

instruction to load the offset of the TLS symbol from the thread pointer. Also

known as the tp relative offset.

!tprelhi

!tprello

!tprel

Like

gprel

relocations except they compute tp relative offsets.

11.4. Floating Point

The Alpha family uses both ieee and VAX floating point numbers.

11.5. Alpha Assembler Directives

as

for the Alpha supports many additional directives for compatibility with the native assembler. This

section describes them only briefly.

These are the additional directives in

as

for the Alpha: