[SPCA] Add example to ASM

semester3/spca/code-examples/01_asm/01_sum.s

@@ -0,0 +1,13 @@
+sum:                        // Label
+    endbr64                 // Indirect Branch target (No effect on code's logic)
+    pushq %rbp              // Preserve caller stack frame
+    movq %rsp, %rbp         // Set up new stack frame
+    movl %edi, -20(%rbp)    // Arg1 register -> stack
+    movl %esi, -24(%rbp)    // Arg2 register -> stack
+    movl -20(%rbp), %edx    // stack[Arg1] -> gp register
+    movl -24(%rbp), %eax    // stack[Arg2] -> gp register
+    addl %edx, %eax         // Add Arg1 + Arg2 -> gp register
+    movl %eax, -4(%rbp)     // result -> stack
+    movl -4(%rbp), %eax     // stack[result] -> return register
+    popq %rbp               // Restore caller stack frame
+    ret                     // jump back to caller

semester3/spca/parts/00_asm/00_intro.tex

@@ -35,3 +35,9 @@ Today, the choices are made based on outside constraints usually. For desktops a
 For embedded systems though, the reduced complexity of RISC makes more sense, but for how long still?
 
 What matters most today are non-technical factors such as existance of code for one ISA or licensing costs (and of course, Geopolitics)
+
+\shade{purple}{Example} A \verb|C| function that simply adds $2$ arguments might be compiled (unoptimized) to this:
+
+\inputcodewithfilename{gas}{code-examples/01_asm/}{01_sum.s}
+
+