| 1 | @c Copyright (C) 2002-2020 Free Software Foundation, Inc. |
| 2 | @c Contributed by David Mosberger-Tang <davidm@hpl.hp.com> |
| 3 | @c This is part of the GAS manual. |
| 4 | @c For copying conditions, see the file as.texinfo. |
| 5 | |
| 6 | @ifset GENERIC |
| 7 | @page |
| 8 | @node IA-64-Dependent |
| 9 | @chapter IA-64 Dependent Features |
| 10 | @end ifset |
| 11 | |
| 12 | @ifclear GENERIC |
| 13 | @node Machine Dependencies |
| 14 | @chapter IA-64 Dependent Features |
| 15 | @end ifclear |
| 16 | |
| 17 | @cindex IA-64 support |
| 18 | @menu |
| 19 | * IA-64 Options:: Options |
| 20 | * IA-64 Syntax:: Syntax |
| 21 | @c * IA-64 Floating Point:: Floating Point // to be written |
| 22 | @c * IA-64 Directives:: IA-64 Machine Directives // to be written |
| 23 | * IA-64 Opcodes:: Opcodes |
| 24 | @end menu |
| 25 | |
| 26 | @node IA-64 Options |
| 27 | @section Options |
| 28 | @cindex IA-64 options |
| 29 | @cindex options for IA-64 |
| 30 | |
| 31 | @table @option |
| 32 | @cindex @code{-mconstant-gp} command-line option, IA-64 |
| 33 | |
| 34 | @item -mconstant-gp |
| 35 | This option instructs the assembler to mark the resulting object file |
| 36 | as using the ``constant GP'' model. With this model, it is assumed |
| 37 | that the entire program uses a single global pointer (GP) value. Note |
| 38 | that this option does not in any fashion affect the machine code |
| 39 | emitted by the assembler. All it does is turn on the EF_IA_64_CONS_GP |
| 40 | flag in the ELF file header. |
| 41 | |
| 42 | @item -mauto-pic |
| 43 | This option instructs the assembler to mark the resulting object file |
| 44 | as using the ``constant GP without function descriptor'' data model. |
| 45 | This model is like the ``constant GP'' model, except that it |
| 46 | additionally does away with function descriptors. What this means is |
| 47 | that the address of a function refers directly to the function's code |
| 48 | entry-point. Normally, such an address would refer to a function |
| 49 | descriptor, which contains both the code entry-point and the GP-value |
| 50 | needed by the function. Note that this option does not in any fashion |
| 51 | affect the machine code emitted by the assembler. All it does is |
| 52 | turn on the EF_IA_64_NOFUNCDESC_CONS_GP flag in the ELF file header. |
| 53 | |
| 54 | @item -milp32 |
| 55 | @itemx -milp64 |
| 56 | @itemx -mlp64 |
| 57 | @itemx -mp64 |
| 58 | These options select the data model. The assembler defaults to @code{-mlp64} |
| 59 | (LP64 data model). |
| 60 | |
| 61 | @item -mle |
| 62 | @itemx -mbe |
| 63 | These options select the byte order. The @code{-mle} option selects little-endian |
| 64 | byte order (default) and @code{-mbe} selects big-endian byte order. Note that |
| 65 | IA-64 machine code always uses little-endian byte order. |
| 66 | |
| 67 | @item -mtune=itanium1 |
| 68 | @itemx -mtune=itanium2 |
| 69 | Tune for a particular IA-64 CPU, @var{itanium1} or @var{itanium2}. The |
| 70 | default is @var{itanium2}. |
| 71 | |
| 72 | @item -munwind-check=warning |
| 73 | @itemx -munwind-check=error |
| 74 | These options control what the assembler will do when performing |
| 75 | consistency checks on unwind directives. @code{-munwind-check=warning} |
| 76 | will make the assembler issue a warning when an unwind directive check |
| 77 | fails. This is the default. @code{-munwind-check=error} will make the |
| 78 | assembler issue an error when an unwind directive check fails. |
| 79 | |
| 80 | @item -mhint.b=ok |
| 81 | @itemx -mhint.b=warning |
| 82 | @itemx -mhint.b=error |
| 83 | These options control what the assembler will do when the @samp{hint.b} |
| 84 | instruction is used. @code{-mhint.b=ok} will make the assembler accept |
| 85 | @samp{hint.b}. @code{-mint.b=warning} will make the assembler issue a |
| 86 | warning when @samp{hint.b} is used. @code{-mhint.b=error} will make |
| 87 | the assembler treat @samp{hint.b} as an error, which is the default. |
| 88 | |
| 89 | @item -x |
| 90 | @itemx -xexplicit |
| 91 | These options turn on dependency violation checking. |
| 92 | |
| 93 | @item -xauto |
| 94 | This option instructs the assembler to automatically insert stop bits where necessary |
| 95 | to remove dependency violations. This is the default mode. |
| 96 | |
| 97 | @item -xnone |
| 98 | This option turns off dependency violation checking. |
| 99 | |
| 100 | @item -xdebug |
| 101 | This turns on debug output intended to help tracking down bugs in the dependency |
| 102 | violation checker. |
| 103 | |
| 104 | @item -xdebugn |
| 105 | This is a shortcut for -xnone -xdebug. |
| 106 | |
| 107 | @item -xdebugx |
| 108 | This is a shortcut for -xexplicit -xdebug. |
| 109 | |
| 110 | @end table |
| 111 | |
| 112 | @cindex IA-64 Syntax |
| 113 | @node IA-64 Syntax |
| 114 | @section Syntax |
| 115 | The assembler syntax closely follows the IA-64 Assembly Language |
| 116 | Reference Guide. |
| 117 | |
| 118 | @menu |
| 119 | * IA-64-Chars:: Special Characters |
| 120 | * IA-64-Regs:: Register Names |
| 121 | * IA-64-Bits:: Bit Names |
| 122 | * IA-64-Relocs:: Relocations |
| 123 | @end menu |
| 124 | |
| 125 | @node IA-64-Chars |
| 126 | @subsection Special Characters |
| 127 | |
| 128 | @cindex line comment character, IA-64 |
| 129 | @cindex IA-64 line comment character |
| 130 | @samp{//} is the line comment token. |
| 131 | |
| 132 | @cindex line separator, IA-64 |
| 133 | @cindex statement separator, IA-64 |
| 134 | @cindex IA-64 line separator |
| 135 | @samp{;} can be used instead of a newline to separate statements. |
| 136 | |
| 137 | @node IA-64-Regs |
| 138 | @subsection Register Names |
| 139 | @cindex IA-64 registers |
| 140 | @cindex register names, IA-64 |
| 141 | |
| 142 | The 128 integer registers are referred to as @samp{r@var{n}}. |
| 143 | The 128 floating-point registers are referred to as @samp{f@var{n}}. |
| 144 | The 128 application registers are referred to as @samp{ar@var{n}}. |
| 145 | The 128 control registers are referred to as @samp{cr@var{n}}. |
| 146 | The 64 one-bit predicate registers are referred to as @samp{p@var{n}}. |
| 147 | The 8 branch registers are referred to as @samp{b@var{n}}. |
| 148 | In addition, the assembler defines a number of aliases: |
| 149 | @samp{gp} (@samp{r1}), @samp{sp} (@samp{r12}), @samp{rp} (@samp{b0}), |
| 150 | @samp{ret0} (@samp{r8}), @samp{ret1} (@samp{r9}), @samp{ret2} (@samp{r10}), |
| 151 | @samp{ret3} (@samp{r9}), @samp{farg@var{n}} (@samp{f8+@var{n}}), and |
| 152 | @samp{fret@var{n}} (@samp{f8+@var{n}}). |
| 153 | |
| 154 | For convenience, the assembler also defines aliases for all named application |
| 155 | and control registers. For example, @samp{ar.bsp} refers to the register |
| 156 | backing store pointer (@samp{ar17}). Similarly, @samp{cr.eoi} refers to |
| 157 | the end-of-interrupt register (@samp{cr67}). |
| 158 | |
| 159 | @node IA-64-Bits |
| 160 | @subsection IA-64 Processor-Status-Register (PSR) Bit Names |
| 161 | @cindex IA-64 Processor-status-Register bit names |
| 162 | @cindex PSR bits |
| 163 | @cindex bit names, IA-64 |
| 164 | |
| 165 | The assembler defines bit masks for each of the bits in the IA-64 |
| 166 | processor status register. For example, @samp{psr.ic} corresponds to |
| 167 | a value of 0x2000. These masks are primarily intended for use with |
| 168 | the @samp{ssm}/@samp{sum} and @samp{rsm}/@samp{rum} |
| 169 | instructions, but they can be used anywhere else where an integer |
| 170 | constant is expected. |
| 171 | |
| 172 | @node IA-64-Relocs |
| 173 | @subsection Relocations |
| 174 | @cindex IA-64 relocations |
| 175 | |
| 176 | In addition to the standard IA-64 relocations, the following relocations are |
| 177 | implemented by @code{@value{AS}}: |
| 178 | |
| 179 | @table @code |
| 180 | @item @@slotcount(@var{V}) |
| 181 | Convert the address offset @var{V} into a slot count. This pseudo |
| 182 | function is available only on VMS. The expression @var{V} must be |
| 183 | known at assembly time: it can't reference undefined symbols or symbols in |
| 184 | different sections. |
| 185 | @end table |
| 186 | |
| 187 | @node IA-64 Opcodes |
| 188 | @section Opcodes |
| 189 | For detailed information on the IA-64 machine instruction set, see the |
| 190 | @c Attempt to work around a very overfull hbox. |
| 191 | @iftex |
| 192 | IA-64 Assembly Language Reference Guide available at |
| 193 | @smallfonts |
| 194 | @example |
| 195 | http://developer.intel.com/design/itanium/arch_spec.htm |
| 196 | @end example |
| 197 | @textfonts |
| 198 | @end iftex |
| 199 | @ifnottex |
| 200 | @uref{http://developer.intel.com/design/itanium/arch_spec.htm,IA-64 Architecture Handbook}. |
| 201 | @end ifnottex |