| 1 | @c Copyright (C) 2015-2018 Free Software Foundation, Inc. |
| 2 | @c This is part of the GAS manual. |
| 3 | @c For copying conditions, see the file as.texinfo. |
| 4 | @c man end |
| 5 | @ifset GENERIC |
| 6 | @page |
| 7 | @node PRU-Dependent |
| 8 | @chapter PRU Dependent Features |
| 9 | @end ifset |
| 10 | |
| 11 | @cindex PRU support |
| 12 | @menu |
| 13 | * PRU Options:: Options |
| 14 | * PRU Syntax:: Syntax |
| 15 | * PRU Relocations:: Relocations |
| 16 | * PRU Directives:: PRU Machine Directives |
| 17 | * PRU Opcodes:: Opcodes |
| 18 | @end menu |
| 19 | |
| 20 | @node PRU Options |
| 21 | @section Options |
| 22 | @cindex PRU options |
| 23 | @cindex options for PRU |
| 24 | |
| 25 | @c man begin OPTIONS |
| 26 | @table @gcctabopt |
| 27 | |
| 28 | @cindex @code{mlink-relax} command line option, PRU |
| 29 | @item -mlink-relax |
| 30 | Assume that LD would optimize LDI32 instructions by checking the upper |
| 31 | 16 bits of the @var{expression}. If they are all zeros, then LD would |
| 32 | shorten the LDI32 instruction to a single LDI. In such case @code{@value{AS}} |
| 33 | will output DIFF relocations for diff expressions. |
| 34 | |
| 35 | @cindex @code{mno-link-relax} command line option, PRU |
| 36 | @item -mno-link-relax |
| 37 | Assume that LD would not optimize LDI32 instructions. As a consequence, |
| 38 | DIFF relocations will not be emitted. |
| 39 | |
| 40 | @cindex @code{mno-warn-regname-label} command line option, PRU |
| 41 | @item -mno-warn-regname-label |
| 42 | Do not warn if a label name matches a register name. Usually assembler |
| 43 | programmers will want this warning to be emitted. C compilers may want |
| 44 | to turn this off. |
| 45 | |
| 46 | @end table |
| 47 | @c man end |
| 48 | |
| 49 | @node PRU Syntax |
| 50 | @section Syntax |
| 51 | @menu |
| 52 | * PRU Chars:: Special Characters |
| 53 | @end menu |
| 54 | |
| 55 | |
| 56 | @node PRU Chars |
| 57 | @subsection Special Characters |
| 58 | |
| 59 | @cindex line comment character, PRU |
| 60 | @cindex PRU line comment character |
| 61 | @samp{#} and @samp{;} are the line comment characters. |
| 62 | |
| 63 | |
| 64 | @node PRU Relocations |
| 65 | @section PRU Machine Relocations |
| 66 | |
| 67 | @cindex machine relocations, PRU |
| 68 | @cindex PRU machine relocations |
| 69 | |
| 70 | @table @code |
| 71 | |
| 72 | @cindex @code{pmem} directive, PRU |
| 73 | @item %pmem(@var{expression}) |
| 74 | Convert @var{expression} from byte-address to a |
| 75 | word-address. In other words, shift right by two. |
| 76 | |
| 77 | @item %label(@var{expression}) |
| 78 | Mark the given operand as a label. This is useful if you need to jump to |
| 79 | a label that matches a register name. |
| 80 | |
| 81 | @smallexample |
| 82 | @group |
| 83 | r1: |
| 84 | jmp r1 ; Will jump to register R1 |
| 85 | jmp %label(r1) ; Will jump to label r1 |
| 86 | @end group |
| 87 | @end smallexample |
| 88 | |
| 89 | @end table |
| 90 | |
| 91 | |
| 92 | @node PRU Directives |
| 93 | @section PRU Machine Directives |
| 94 | |
| 95 | @cindex machine directives, PRU |
| 96 | @cindex PRU machine directives |
| 97 | |
| 98 | @table @code |
| 99 | |
| 100 | @cindex @code{align} directive, PRU |
| 101 | @item .align @var{expression} [, @var{expression}] |
| 102 | This is the generic @code{.align} directive, however |
| 103 | this aligns to a power of two. |
| 104 | |
| 105 | @cindex @code{word} directive, PRU |
| 106 | @item .word @var{expression} |
| 107 | Create an aligned constant 4 bytes in size. |
| 108 | |
| 109 | @cindex @code{dword} directive, PRU |
| 110 | @item .dword @var{expression} |
| 111 | Create an aligned constant 8 bytes in size. |
| 112 | |
| 113 | @cindex @code{2byte} directive, PRU |
| 114 | @item .2byte @var{expression} |
| 115 | Create an unaligned constant 2 bytes in size. |
| 116 | |
| 117 | @cindex @code{4byte} directive, PRU |
| 118 | @item .4byte @var{expression} |
| 119 | Create an unaligned constant 4 bytes in size. |
| 120 | |
| 121 | @cindex @code{8byte} directive, PRU |
| 122 | @item .8byte @var{expression} |
| 123 | Create an unaligned constant 8 bytes in size. |
| 124 | |
| 125 | @cindex @code{16byte} directive, PRU |
| 126 | @item .16byte @var{expression} |
| 127 | Create an unaligned constant 16 bytes in size. |
| 128 | |
| 129 | @cindex @code{set no_warn_regname_label} directive, PRU |
| 130 | @item .set no_warn_regname_label |
| 131 | Do not output warnings when a label name matches a register name. Equivalent |
| 132 | to passing the @code{-mno-warn-regname-label} command line option. |
| 133 | |
| 134 | @end table |
| 135 | |
| 136 | @node PRU Opcodes |
| 137 | @section Opcodes |
| 138 | |
| 139 | @cindex PRU opcodes |
| 140 | @cindex opcodes for PRU |
| 141 | @code{@value{AS}} implements all the standard PRU core V3 opcodes in the |
| 142 | original pasm assembler. Older cores are not supported by @code{@value{AS}}. |
| 143 | |
| 144 | GAS also implements the LDI32 pseudo instruction for loading a 32-bit |
| 145 | immediate value into a register. |
| 146 | |
| 147 | @smallexample |
| 148 | ldi32 sp, __stack_top |
| 149 | ldi32 r14, 0x12345678 |
| 150 | @end smallexample |