as: Literal Position Directive
9.54.5.5 literal_position
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When using '--text-section-literals' to place literals inline in the
section being assembled, the '.literal_position' directive can be used
to mark a potential location for a literal pool.
.literal_position
The '.literal_position' directive is ignored when the
'--text-section-literals' option is not used or when 'L32R' instructions
use the absolute addressing mode.
The assembler will automatically place text section literal pools
before 'ENTRY' instructions, so the '.literal_position' directive is
only needed to specify some other location for a literal pool. You may
need to add an explicit jump instruction to skip over an inline literal
pool.
For example, an interrupt vector does not begin with an 'ENTRY'
instruction so the assembler will be unable to automatically find a good
place to put a literal pool. Moreover, the code for the interrupt
vector must be at a specific starting address, so the literal pool
cannot come before the start of the code. The literal pool for the
vector must be explicitly positioned in the middle of the vector (before
any uses of the literals, due to the negative offsets used by
PC-relative 'L32R' instructions). The '.literal_position' directive can
be used to do this. In the following code, the literal for 'M' will
automatically be aligned correctly and is placed after the unconditional
jump.
.global M
code_start:
j continue
.literal_position
.align 4
continue:
movi a4, M
Info Catalog
as: Literal Directive
as: Xtensa Directives
as: Literal Prefix Directive