(as.info.gz) Literal Directive

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 9.40.5.4 literal
 ................
 
 The `.literal' directive is used to define literal pool data, i.e.,
 read-only 32-bit data accessed via `L32R' instructions.
 
          .literal LABEL, VALUE[, VALUE...]
 
    This directive is similar to the standard `.word' directive, except
 that the actual location of the literal data is determined by the
 assembler and linker, not by the position of the `.literal' directive.
 Using this directive gives the assembler freedom to locate the literal
 data in the most appropriate place and possibly to combine identical
 literals.  For example, the code:
 
          entry sp, 40
          .literal .L1, sym
          l32r    a4, .L1
 
    can be used to load a pointer to the symbol `sym' into register
 `a4'.  The value of `sym' will not be placed between the `ENTRY' and
 `L32R' instructions; instead, the assembler puts the data in a literal
 pool.
 
    Literal pools are placed by default in separate literal sections;
 however, when using the `--text-section-literals' option ( Command
 Line Options Xtensa Options.), the literal pools for PC-relative mode
 `L32R' instructions are placed in the current section.(1) These text
 section literal pools are created automatically before `ENTRY'
 instructions and manually after `.literal_position' directives (
 literal_position Literal Position Directive.).  If there are no
 preceding `ENTRY' instructions, explicit `.literal_position' directives
 must be used to place the text section literal pools; otherwise, `as'
 will report an error.
 
    When literals are placed in separate sections, the literal section
 names are derived from the names of the sections where the literals are
 defined.  The base literal section names are `.literal' for PC-relative
 mode `L32R' instructions and `.lit4' for absolute mode `L32R'
 instructions ( absolute-literals Absolute Literals Directive.).
 These base names are used for literals defined in the default `.text'
 section.  For literals defined in other sections or within the scope of
 a `literal_prefix' directive ( literal_prefix Literal Prefix
 Directive.), the following rules determine the literal section name:
 
   1. If the current section is a member of a section group, the literal
      section name includes the group name as a suffix to the base
      `.literal' or `.lit4' name, with a period to separate the base
      name and group name.  The literal section is also made a member of
      the group.
 
   2. If the current section name (or `literal_prefix' value) begins with
      "`.gnu.linkonce.KIND.'", the literal section name is formed by
      replacing "`.KIND'" with the base `.literal' or `.lit4' name.  For
      example, for literals defined in a section named
      `.gnu.linkonce.t.func', the literal section will be
      `.gnu.linkonce.literal.func' or `.gnu.linkonce.lit4.func'.
 
   3. If the current section name (or `literal_prefix' value) ends with
      `.text', the literal section name is formed by replacing that
      suffix with the base `.literal' or `.lit4' name.  For example, for
      literals defined in a section named `.iram0.text', the literal
      section will be `.iram0.literal' or `.iram0.lit4'.
 
   4. If none of the preceding conditions apply, the literal section
      name is formed by adding the base `.literal' or `.lit4' name as a
      suffix to the current section name (or `literal_prefix' value).
 
    ---------- Footnotes ----------
 
    (1) Literals for the `.init' and `.fini' sections are always placed
 in separate sections, even when `--text-section-literals' is enabled.
 

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