diff --git a/ka/ABI b/ka/ABI
index 315448f..180ca88 100644
--- a/ka/ABI
+++ b/ka/ABI
@@ -19,16 +19,16 @@ A function's assembly code looks like this:
         ret
 'N' is the number of local variables used by the function.
 
-The above code is equivalent to the following, but much faster:
+The above code is equivalent to the following, but faster:
     label:
-        mov [rsp-8], rbp
-        lea rbp, [rsp-8]
-        sub rsp, (N+1)*8
+        push rbp
+        mov rbp, rsp
+        sub rsp, N*8
         ...
         ...
         ...
-        lea rsp, [rbp+8]
-        mov rbp, [rbp]
+        mov rsp, rbp
+        pop rbp
         ret
 
 Between the 'enter' and the 'leave', the stack looks like this:
@@ -73,7 +73,7 @@ Aside from the DF flag, a function cannot assume anything about the state
 of the flags in the FLG register.
 
 Passing parameters is done using the following registers, in that order:
-    ax0-ax9, a10-a31
+    a0-a15
 
 The stack is never used for argument passing, except for variadic functions,
 cf the next section. If you need to pass large structures of data, pass
@@ -81,14 +81,14 @@ their address in an appropriate register.
 
 Return values are passed in 'rax'. If the return value does not fit
 and require more registers, use the following registers, in that order:
-    rax, rdx, a16-a31
+    rax, rdx
 
 The following registers are volatile; the calling function cannot assume
 that they will be left unmodified by the called function:
-    rax, rcx, rdx, rx8-r31, ax0-a31
+    rax, rcx, rdx, r8-r15, a0-a15
 
 The following registers are nonvolatile; the called function must preserve them:
-    rbx, rsi, rdi, nx0-n31, rbp, rsp
+    rbx, rsi, rdi, n0-n15, rbp, rsp
 
 #------------------------------------------------------------------------------#
 
@@ -127,12 +127,10 @@ as an offset register in the [reg+reg(*/+...)] memory formats; in these case,
 
 The following registers can only be used by the supervisor:
 - Fast global variables for the supervisor:
-    sa0-sa7
-- Debugging registers for the supervisor:
-    dr0-dr7
+    sa0-sa3
 
 The following registers cannot be referenced by machine code at all:
-    px0-px1, fc0-fc2, cr0-cr7
+    px0-px1, fc0-fc2, cr0-cr3
 
 #------------------------------------------------------------------------------#
 
diff --git a/ka/sys/intr/common.k b/ka/sys/intr/common.k
index 1c46a4c..0e6cba4 100644
--- a/ka/sys/intr/common.k
+++ b/ka/sys/intr/common.k
@@ -2,19 +2,17 @@
 ; See the LICENSE file in the project root for more information.
 
 TrapHandlers.prolog:
-    sub rsp, rbp, 32
+    sub rsp, rbp, 24
     mov q[rbp-8], r11
     mov q[rbp-16], r12
     mov q[rbp-24], r13
-    cmp q[rsp], r13
-    crash.z
 
     jmp rax ; go back
 
 TrapHandlers.epilog:
-    mov r11, q[rbp-8]
-    mov r12, q[rbp-16]
     mov r13, q[rbp-24]
+    mov r12, q[rbp-16]
+    mov r11, q[rbp-8]
 
     mov ax0, r11
     call IDT.DoneHandling