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author | johannst <johannst@users.noreply.github.com> | 2021-02-28 20:37:15 +0000 |
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committer | johannst <johannst@users.noreply.github.com> | 2021-02-28 20:37:15 +0000 |
commit | fe84155562f3e6d51b94155197ab5606f2e3bebe (patch) | |
tree | 86ad1593fee654a8e35f4251bc32eb83a49fe388 /print.html | |
parent | a2c2408d431a55d5b1db44fbb2495a83f52cfcaf (diff) | |
download | notes-fe84155562f3e6d51b94155197ab5606f2e3bebe.tar.gz notes-fe84155562f3e6d51b94155197ab5606f2e3bebe.zip |
deploy: 5e76b1948f7d7f499993862933f0622cf76d83ff
Diffstat (limited to 'print.html')
-rw-r--r-- | print.html | 256 |
1 files changed, 252 insertions, 4 deletions
@@ -83,7 +83,7 @@ <nav id="sidebar" class="sidebar" aria-label="Table of contents"> <div id="sidebar-scrollbox" class="sidebar-scrollbox"> - <ol class="chapter"><li class="expanded affix "><a href="intro.html">Introduction</a></li><li class="expanded "><a href="tools/index.html"><strong aria-hidden="true">1.</strong> Tools</a></li><li><ol class="section"><li class="expanded "><a href="tools/zsh.html"><strong aria-hidden="true">1.1.</strong> zsh</a></li><li class="expanded "><a href="tools/bash.html"><strong aria-hidden="true">1.2.</strong> bash</a></li><li class="expanded "><a href="tools/fish.html"><strong aria-hidden="true">1.3.</strong> fish</a></li><li class="expanded "><a href="tools/tmux.html"><strong aria-hidden="true">1.4.</strong> tmux</a></li><li class="expanded "><a href="tools/git.html"><strong aria-hidden="true">1.5.</strong> git</a></li><li class="expanded "><a href="tools/awk.html"><strong aria-hidden="true">1.6.</strong> awk</a></li><li class="expanded "><a href="tools/emacs.html"><strong aria-hidden="true">1.7.</strong> emacs</a></li><li class="expanded "><a href="tools/gpg.html"><strong aria-hidden="true">1.8.</strong> gpg</a></li><li class="expanded "><a href="tools/gdb.html"><strong aria-hidden="true">1.9.</strong> gdb</a></li><li class="expanded "><a href="tools/radare2.html"><strong aria-hidden="true">1.10.</strong> radare2</a></li><li class="expanded "><a href="tools/qemu.html"><strong aria-hidden="true">1.11.</strong> qemu</a></li></ol></li><li class="expanded "><a href="monitor/index.html"><strong aria-hidden="true">2.</strong> Resource analysis & monitor</a></li><li><ol class="section"><li class="expanded "><a href="monitor/lsof.html"><strong aria-hidden="true">2.1.</strong> lsof</a></li><li class="expanded "><a href="monitor/ss.html"><strong aria-hidden="true">2.2.</strong> ss</a></li><li class="expanded "><a href="monitor/pidstat.html"><strong aria-hidden="true">2.3.</strong> pidstat</a></li><li class="expanded "><a href="monitor/pgrep.html"><strong aria-hidden="true">2.4.</strong> pgrep</a></li><li class="expanded "><a href="monitor/pmap.html"><strong aria-hidden="true">2.5.</strong> pmap</a></li><li class="expanded "><a href="monitor/pstack.html"><strong aria-hidden="true">2.6.</strong> pstack</a></li></ol></li><li class="expanded "><a href="trace_profile/index.html"><strong aria-hidden="true">3.</strong> Trace and Profile</a></li><li><ol class="section"><li class="expanded "><a href="trace_profile/strace.html"><strong aria-hidden="true">3.1.</strong> strace</a></li><li class="expanded "><a href="trace_profile/ltrace.html"><strong aria-hidden="true">3.2.</strong> ltrace</a></li><li class="expanded "><a href="trace_profile/perf.html"><strong aria-hidden="true">3.3.</strong> perf</a></li><li class="expanded "><a href="trace_profile/oprofile.html"><strong aria-hidden="true">3.4.</strong> OProfile</a></li><li class="expanded "><a href="trace_profile/time.html"><strong aria-hidden="true">3.5.</strong> time</a></li></ol></li><li class="expanded "><a href="binary/index.html"><strong aria-hidden="true">4.</strong> Binary</a></li><li><ol class="section"><li class="expanded "><a href="binary/od.html"><strong aria-hidden="true">4.1.</strong> od</a></li><li class="expanded "><a href="binary/xxd.html"><strong aria-hidden="true">4.2.</strong> xxd</a></li><li class="expanded "><a href="binary/readelf.html"><strong aria-hidden="true">4.3.</strong> readelf</a></li><li class="expanded "><a href="binary/objdump.html"><strong aria-hidden="true">4.4.</strong> objdump</a></li><li class="expanded "><a href="binary/nm.html"><strong aria-hidden="true">4.5.</strong> nm</a></li></ol></li><li class="expanded "><a href="development/index.html"><strong aria-hidden="true">5.</strong> Development</a></li><li><ol class="section"><li class="expanded "><a href="development/c++filt.html"><strong aria-hidden="true">5.1.</strong> c++filt</a></li><li class="expanded "><a href="development/c++.html"><strong aria-hidden="true">5.2.</strong> c++</a></li><li class="expanded "><a href="development/glibc.html"><strong aria-hidden="true">5.3.</strong> glibc</a></li><li class="expanded "><a href="development/gcc.html"><strong aria-hidden="true">5.4.</strong> gcc</a></li><li class="expanded "><a href="development/make.html"><strong aria-hidden="true">5.5.</strong> make</a></li><li class="expanded "><a href="development/ld.so.html"><strong aria-hidden="true">5.6.</strong> ld.so</a></li></ol></li><li class="expanded "><a href="arch/index.html"><strong aria-hidden="true">6.</strong> Arch</a></li><li><ol class="section"><li class="expanded "><a href="arch/x86_64.html"><strong aria-hidden="true">6.1.</strong> x86_64</a></li><li class="expanded "><a href="arch/arm64.html"><strong aria-hidden="true">6.2.</strong> arm64</a></li></ol></li></ol> + <ol class="chapter"><li class="expanded affix "><a href="intro.html">Introduction</a></li><li class="expanded "><a href="tools/index.html"><strong aria-hidden="true">1.</strong> Tools</a></li><li><ol class="section"><li class="expanded "><a href="tools/zsh.html"><strong aria-hidden="true">1.1.</strong> zsh</a></li><li class="expanded "><a href="tools/bash.html"><strong aria-hidden="true">1.2.</strong> bash</a></li><li class="expanded "><a href="tools/fish.html"><strong aria-hidden="true">1.3.</strong> fish</a></li><li class="expanded "><a href="tools/tmux.html"><strong aria-hidden="true">1.4.</strong> tmux</a></li><li class="expanded "><a href="tools/git.html"><strong aria-hidden="true">1.5.</strong> git</a></li><li class="expanded "><a href="tools/awk.html"><strong aria-hidden="true">1.6.</strong> awk</a></li><li class="expanded "><a href="tools/emacs.html"><strong aria-hidden="true">1.7.</strong> emacs</a></li><li class="expanded "><a href="tools/gpg.html"><strong aria-hidden="true">1.8.</strong> gpg</a></li><li class="expanded "><a href="tools/gdb.html"><strong aria-hidden="true">1.9.</strong> gdb</a></li><li class="expanded "><a href="tools/radare2.html"><strong aria-hidden="true">1.10.</strong> radare2</a></li><li class="expanded "><a href="tools/qemu.html"><strong aria-hidden="true">1.11.</strong> qemu</a></li></ol></li><li class="expanded "><a href="monitor/index.html"><strong aria-hidden="true">2.</strong> Resource analysis & monitor</a></li><li><ol class="section"><li class="expanded "><a href="monitor/lsof.html"><strong aria-hidden="true">2.1.</strong> lsof</a></li><li class="expanded "><a href="monitor/ss.html"><strong aria-hidden="true">2.2.</strong> ss</a></li><li class="expanded "><a href="monitor/pidstat.html"><strong aria-hidden="true">2.3.</strong> pidstat</a></li><li class="expanded "><a href="monitor/pgrep.html"><strong aria-hidden="true">2.4.</strong> pgrep</a></li><li class="expanded "><a href="monitor/pmap.html"><strong aria-hidden="true">2.5.</strong> pmap</a></li><li class="expanded "><a href="monitor/pstack.html"><strong aria-hidden="true">2.6.</strong> pstack</a></li></ol></li><li class="expanded "><a href="trace_profile/index.html"><strong aria-hidden="true">3.</strong> Trace and Profile</a></li><li><ol class="section"><li class="expanded "><a href="trace_profile/strace.html"><strong aria-hidden="true">3.1.</strong> strace</a></li><li class="expanded "><a href="trace_profile/ltrace.html"><strong aria-hidden="true">3.2.</strong> ltrace</a></li><li class="expanded "><a href="trace_profile/perf.html"><strong aria-hidden="true">3.3.</strong> perf</a></li><li class="expanded "><a href="trace_profile/oprofile.html"><strong aria-hidden="true">3.4.</strong> OProfile</a></li><li class="expanded "><a href="trace_profile/time.html"><strong aria-hidden="true">3.5.</strong> time</a></li></ol></li><li class="expanded "><a href="binary/index.html"><strong aria-hidden="true">4.</strong> Binary</a></li><li><ol class="section"><li class="expanded "><a href="binary/od.html"><strong aria-hidden="true">4.1.</strong> od</a></li><li class="expanded "><a href="binary/xxd.html"><strong aria-hidden="true">4.2.</strong> xxd</a></li><li class="expanded "><a href="binary/readelf.html"><strong aria-hidden="true">4.3.</strong> readelf</a></li><li class="expanded "><a href="binary/objdump.html"><strong aria-hidden="true">4.4.</strong> objdump</a></li><li class="expanded "><a href="binary/nm.html"><strong aria-hidden="true">4.5.</strong> nm</a></li></ol></li><li class="expanded "><a href="development/index.html"><strong aria-hidden="true">5.</strong> Development</a></li><li><ol class="section"><li class="expanded "><a href="development/c++filt.html"><strong aria-hidden="true">5.1.</strong> c++filt</a></li><li class="expanded "><a href="development/c++.html"><strong aria-hidden="true">5.2.</strong> c++</a></li><li class="expanded "><a href="development/glibc.html"><strong aria-hidden="true">5.3.</strong> glibc</a></li><li class="expanded "><a href="development/gcc.html"><strong aria-hidden="true">5.4.</strong> gcc</a></li><li class="expanded "><a href="development/make.html"><strong aria-hidden="true">5.5.</strong> make</a></li><li class="expanded "><a href="development/ld.so.html"><strong aria-hidden="true">5.6.</strong> ld.so</a></li></ol></li><li class="expanded "><a href="arch/index.html"><strong aria-hidden="true">6.</strong> Arch</a></li><li><ol class="section"><li class="expanded "><a href="arch/x86_64.html"><strong aria-hidden="true">6.1.</strong> x86_64</a></li><li class="expanded "><a href="arch/arm64.html"><strong aria-hidden="true">6.2.</strong> arm64</a></li><li class="expanded "><a href="arch/armv7.html"><strong aria-hidden="true">6.3.</strong> armv7</a></li></ol></li></ol> </div> <div id="sidebar-resize-handle" class="sidebar-resize-handle"></div> </nav> @@ -2359,6 +2359,7 @@ As we can see the offset from relocation at index <code>0</code> points to <code <ul> <li><a href="arch/./x86_64.html">x86_64</a></li> <li><a href="arch/./arm64.html">arm64</a></li> +<li><a href="arch/./armv7.html">armv7</a></li> </ul> <h1><a class="header" href="#x86_64" id="x86_64">x86_64</a></h1> <p>keywords: x86_64, x86, abi</p> @@ -2565,6 +2566,7 @@ Hi ASM-World! <li><a href="https://software.intel.com/content/www/us/en/develop/download/intel-64-and-ia-32-architectures-sdm-combined-volumes-3a-3b-3c-and-3d-system-programming-guide.html">Intel 64 Vol3: System Programming Guide</a></li> <li><a href="https://sourceware.org/binutils/docs/as">GNU Assembler</a></li> <li><a href="https://sourceware.org/binutils/docs/as/Pseudo-Ops.html#Pseudo-Ops">GNU Assembler Directives</a></li> +<li><a href="https://sourceware.org/binutils/docs/as/i386_002dDependent.html">GNU Assembler <code>x86_64</code> dependent features</a></li> </ul> <h1><a class="header" href="#arm64" id="arm64">arm64</a></h1> <p>keywords: arm64, aarch64, abi</p> @@ -2682,7 +2684,12 @@ x0 64 bit </ul> <h3><a class="header" href="#stack-1" id="stack-1">Stack</a></h3> <ul> -<li>grows downwards</li> +<li>full descending +<ul> +<li>full: <code>sp</code> points to the last used location (valid item)</li> +<li>descending: stack grows downwards</li> +</ul> +</li> <li><code>sp</code> must be 16byte aligned when used to access memory for r/w</li> <li><code>sp</code> must be 16byte aligned on public interface interfaces</li> </ul> @@ -2779,11 +2786,252 @@ required when compiling natively on arm64.</p> <h2><a class="header" href="#references-2" id="references-2">References</a></h2> <ul> <li><a href="https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst">Procedure Call Standard ARM64</a></li> -<li><a href="https://developer.arm.com/documentation/den0024/a">ARMv8-A Programmer's Guide</a></li> +<li><a href="https://developer.arm.com/documentation/den0024/latest">ARMv8-A Programmer's Guide</a></li> <li><a href="https://developer.arm.com/documentation/ddi0487/latest">ARMv8-A Architecture Reference Manual</a></li> -<li><a href="https://developer.arm.com/documentation/dai0527/a">AppNote: ARMv8 Bare-metal boot code</a></li> +<li><a href="https://developer.arm.com/documentation/dai0527/latest">AppNote: ARMv8 Bare-metal boot code</a></li> +<li><a href="https://sourceware.org/binutils/docs/as">GNU Assembler</a></li> +<li><a href="https://sourceware.org/binutils/docs/as/Pseudo-Ops.html#Pseudo-Ops">GNU Assembler Directives</a></li> +<li><a href="https://sourceware.org/binutils/docs/as/AArch64_002dDependent.html">GNU Assembler <code>AArch64</code> dependent features</a></li> +</ul> +<h1><a class="header" href="#armv7a" id="armv7a">armv7a</a></h1> +<p>keywords: arm, armv7, abi</p> +<ul> +<li>ISA type: <code>RISC</code></li> +<li>Endianness: <code>little</code>, <code>big</code></li> +</ul> +<h2><a class="header" href="#registers-2" id="registers-2">Registers</a></h2> +<h3><a class="header" href="#general-purpose-registers-1" id="general-purpose-registers-1">General purpose registers</a></h3> +<pre><code class="language-markdown">bytes +[3:0] alt desc +--------------------------------------------- +r0-r12 general purpose registers +r11 fp +r13 sp stack pointer +r14 lr link register +r15 pc program counter +</code></pre> +<h3><a class="header" href="#special-registers" id="special-registers">Special registers</a></h3> +<pre><code class="language-markdown">bytes +[3:0] desc +--------------------------------------------- +cpsr current program status register +</code></pre> +<h3><a class="header" href="#cpsr-register" id="cpsr-register">CPSR register</a></h3> +<pre><code class="language-markdown">cpsr +bits desc +----------------------------- + [31] N negative flag + [30] Z zero flag + [29] C carry flag + [28] V overflow flag + [27] Q cummulative saturation (sticky) + [9] E load/store endianness + [8] A disable asynchronous aborts + [7] I disable IRQ + [6] F disable FIQ + [5] T indicate Thumb state +[4:0] M process mode (USR, FIQ, IRQ, SVC, ABT, UND, SYS) +</code></pre> +<h2><a class="header" href="#instructions-cheatsheet-1" id="instructions-cheatsheet-1">Instructions cheatsheet</a></h2> +<h3><a class="header" href="#accessing-system-registers-1" id="accessing-system-registers-1">Accessing system registers</a></h3> +<p>Reading from system registers:</p> +<pre><code class="language-armasm">mrs r0, cpsr // move cpsr into r0 +</code></pre> +<p>Writing to system registers:</p> +<pre><code class="language-armasm">msr cpsr, r0 // move r0 into cpsr +</code></pre> +<h3><a class="header" href="#control-flow-2" id="control-flow-2">Control Flow</a></h3> +<pre><code class="language-armasm">b <lable> // relative forward/back branch +bl <lable> // relative forward/back branch & link return addr in r14 (LR) + +// branch & exchange (can change between ARM & Thumb instruction set) +// bit Rm[0] == 0 -> ARM +// bit Rm[0] == 1 -> Thumb +bx <Rm> // absolute branch to address in register Rm +blx <Rm> // absolute branch to address in register Rm & + // link return addr in r14 (LR) +</code></pre> +<h3><a class="header" href="#loadstore" id="loadstore">Load/Store</a></h3> +<p>Different addressing modes.</p> +<pre><code class="language-armasm">str r1, [r0] // [r0]=r1 +str r1, [r0, #4] // [r0+4]=r1 +str r1, [r0, #4]! // r0+=4; [r0]=r1 +str r1, [r0], 4 // [r0]=r1; r0+=4 +</code></pre> +<p>Load/store multiple registers full-descending.</p> +<pre><code class="language-armasm">stmfd r0!, {r1-r2, r5} // r0-=4; [r0]=r5 + // r0-=4; [r0]=r2 + // r0-=4; [r0]=r1 +ldmfd r0!, {r1-r2, r5} // r1=[r0]; r0+=4 + // r2=[r0]; r0+=4 + // r5=[r0]; r0+=4 +</code></pre> +<blockquote> +<p><code>!</code> is optional but has the effect to update the base pointer register <code>r0</code> here.</p> +</blockquote> +<p>Push/Pop</p> +<pre><code class="language-armasm">push {r0-r2} // effectively stmfd sp!, {r0-r2} +pop {r0-r2} // effectively ldmfd sp!, {r0-r2} +</code></pre> +<h2><a class="header" href="#procedure-call-standard-arm-a-hrefhttpsgithubcomarm-softwareabi-aablobmasteraapcs32aapcs32rstaapcs32a" id="procedure-call-standard-arm-a-hrefhttpsgithubcomarm-softwareabi-aablobmasteraapcs32aapcs32rstaapcs32a">Procedure Call Standard ARM (<a href="https://github.com/ARM-software/abi-aa/blob/master/aapcs32/aapcs32.rst"><code>aapcs32</code></a>)</a></h2> +<h3><a class="header" href="#passing-arguments-to-functions-2" id="passing-arguments-to-functions-2">Passing arguments to functions</a></h3> +<ul> +<li>integer/pointer arguments +<pre><code class="language-markdown">reg arg +----------- +r0 1 +.. .. +r3 4 +</code></pre> +</li> +<li>a double word (64bit) is passed in two consecutive registers (eg <code>r1+r2</code>)</li> +<li>additional arguments are passed on the stack. Arguments are pushed +<code>right-to-left (RTL)</code>, meaning next arguments are closer to current <code>sp</code>. +<pre><code class="language-markdown">void take(..., int a5, int a6); + | | | ... | Hi + | +-->| a6 | | + +---------->| a5 | <-SP | + +-----+ v + | ... | Lo +</code></pre> +</li> +</ul> +<h3><a class="header" href="#return-values-from-functions-2" id="return-values-from-functions-2">Return values from functions</a></h3> +<ul> +<li>integer/pointer return values +<pre><code class="language-markdown">reg size +----------------- +r0 32 bit +r0+r1 64 bit +</code></pre> +</li> +</ul> +<h3><a class="header" href="#callee-saved-registers-2" id="callee-saved-registers-2">Callee saved registers</a></h3> +<ul> +<li><code>r4</code> - <code>r11</code></li> +<li><code>sp</code></li> +</ul> +<h3><a class="header" href="#stack-2" id="stack-2">Stack</a></h3> +<ul> +<li>full descending +<ul> +<li>full: <code>sp</code> points to the last used location (valid item)</li> +<li>descending: stack grows downwards</li> +</ul> +</li> +<li><code>sp</code> must be 4byte aligned (word boundary) at all time</li> +<li><code>sp</code> must be 8byte aligned on public interface interfaces</li> +</ul> +<h3><a class="header" href="#frame-chain-1" id="frame-chain-1">Frame chain</a></h3> +<ul> +<li>not strictly required by each platform</li> +<li>linked list of stack-frames</li> +<li>each frame links to the frame of its caller by a <code>frame record</code> +<ul> +<li>a frame record is described as a <code>(FP,LR)</code> pair (2x32bit)</li> +</ul> +</li> +<li><code>r11 (FP)</code> must point to the frame record of the current stack-frame +<pre><code class="language-markdown"> +------+ Hi + | 0 | frame0 | + +->| 0 | | + | | ... | | + | +------+ | + | | LR | frame1 | + +--| FP |<-+ | + | ... | | | + +------+ | | + | LR | | current | +r11 ->| FP |--+ frame v + | ... | Lo +</code></pre> +</li> +<li>end of the frame chain is indicated by following frame record <code>(0,-)</code></li> +<li>location of the frame record in the stack frame is not specified</li> +<li><code>r11</code> is not updated before the new frame record is fully constructed</li> +</ul> +<h3><a class="header" href="#function-prologue--epilogue-2" id="function-prologue--epilogue-2">Function prologue & epilogue</a></h3> +<ul> +<li>prologue +<pre><code class="language-armasm">push {fp, lr} +mov fp, sp // FP points to frame record +</code></pre> +</li> +<li>epilogue +<pre><code class="language-armasm">pop {fp, pc} // pop LR directly into PC +</code></pre> +</li> +</ul> +<h2><a class="header" href="#asm-skeleton-2" id="asm-skeleton-2">ASM skeleton</a></h2> +<p>Small assembler skeleton, ready to use with following properties:</p> +<ul> +<li>use raw Linux syscalls (<code>man 2 syscall</code> for ABI)</li> +<li>no <code>C runtime (crt)</code></li> +<li>gnu assembler <a href="https://sourceware.org/binutils/docs/as"><code>gas</code></a></li> +</ul> +<pre><code class="language-armasm">// file: greet.S + +#include <asm/unistd.h> // syscall NRs + + .arch armv7-a + + .section .text, "ax" + .balign 4 + + // Emit `arm` instructions, same as `.arm` directive. + .code 32 + .global _start +_start: + // Branch with link and exchange instruction set. + blx _do_greet + + mov r0, #0 // exit code + mov r7, #__NR_exit // exit(2) syscall + swi 0x0 + + // Emit `thumb` instructions, same as `.thumb` directive. + .code 16 + .thumb_func +_do_greet: + mov r0, #2 // fd + ldr r1, =greeting // buf + ldr r2, =greeting_len // &len + ldr r2, [r2] // len + mov r7, #__NR_write // write(2) syscall + swi 0x0 + + // Branch and exchange instruction set. + bx lr + + .balign 8 // align data on 8byte boundary + .section .rodata, "a" +greeting: + .asciz "Hi ASM-World!\n" +greeting_len: + .int .-greeting +</code></pre> +<blockquote> +<p>man gcc: <code>file.S</code> assembler code that must be preprocessed.</p> +</blockquote> +<p>To cross-compile and run:</p> +<pre><code class="language-bash">> arm-linux-gnueabi-gcc -o greet greet.S -nostartfiles -nostdlib \ + -Wl,--dynamic-linker=/usr/arm-linux-gnueabi/lib/ld-linux.so.3 \ + && qemu-arm ./greet +Hi ASM-World! +</code></pre> +<blockquote> +<p>Cross-compiling on <code>Ubuntu 20.04 (x86_64)</code>, paths might differ on other +distributions. Explicitly specifying the dynamic linker should not be +required when compiling natively on arm.</p> +</blockquote> +<h2><a class="header" href="#references-3" id="references-3">References</a></h2> +<ul> +<li><a href="https://github.com/ARM-software/abi-aa/blob/master/aapcs32/aapcs32.rst">Procedure Call Standard ARM</a></li> +<li><a href="https://developer.arm.com/documentation/den0013/latest">ARMv7-A Programmer's Guide</a></li> +<li><a href="https://developer.arm.com/documentation/ddi0406/latest">ARMv7-A Architecture Reference Manual</a></li> <li><a href="https://sourceware.org/binutils/docs/as">GNU Assembler</a></li> <li><a href="https://sourceware.org/binutils/docs/as/Pseudo-Ops.html#Pseudo-Ops">GNU Assembler Directives</a></li> +<li><a href="https://sourceware.org/binutils/docs/as/ARM_002dDependent.html">GNU Assembler <code>ARM</code> dependent features</a></li> </ul> </main> |