as: Loc

1 
1 7.55 '.loc FILENO LINENO [COLUMN] [OPTIONS]'
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1 
1 When emitting DWARF2 line number information, the '.loc' directive will
1 add a row to the '.debug_line' line number matrix corresponding to the
1 immediately following assembly instruction.  The FILENO, LINENO, and
1 optional COLUMN arguments will be applied to the '.debug_line' state
1 machine before the row is added.
1 
1    The OPTIONS are a sequence of the following tokens in any order:
1 
1 'basic_block'
1      This option will set the 'basic_block' register in the
1      '.debug_line' state machine to 'true'.
1 
1 'prologue_end'
1      This option will set the 'prologue_end' register in the
1      '.debug_line' state machine to 'true'.
1 
1 'epilogue_begin'
1      This option will set the 'epilogue_begin' register in the
1      '.debug_line' state machine to 'true'.
1 
1 'is_stmt VALUE'
1      This option will set the 'is_stmt' register in the '.debug_line'
1      state machine to 'value', which must be either 0 or 1.
1 
1 'isa VALUE'
1      This directive will set the 'isa' register in the '.debug_line'
1      state machine to VALUE, which must be an unsigned integer.
1 
1 'discriminator VALUE'
1      This directive will set the 'discriminator' register in the
1      '.debug_line' state machine to VALUE, which must be an unsigned
1      integer.
1 
1 'view VALUE'
1      This option causes a row to be added to '.debug_line' in reference
1      to the current address (which might not be the same as that of the
1      following assembly instruction), and to associate VALUE with the
1      'view' register in the '.debug_line' state machine.  If VALUE is a
1      label, both the 'view' register and the label are set to the number
1      of prior '.loc' directives at the same program location.  If VALUE
1      is the literal '0', the 'view' register is set to zero, and the
1      assembler asserts that there aren't any prior '.loc' directives at
1      the same program location.  If VALUE is the literal '-0', the
1      assembler arrange for the 'view' register to be reset in this row,
1      even if there are prior '.loc' directives at the same program
1      location.
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