diff --git a/kernel/arch/i686/Signal.S b/kernel/arch/i686/Signal.S
index 9621c2cf..4bf29015 100644
--- a/kernel/arch/i686/Signal.S
+++ b/kernel/arch/i686/Signal.S
@@ -16,9 +16,8 @@ signal_trampoline:
 	movl 36(%esp), %eax
 
 	// align stack to 16 bytes
-	movl %esp, %ebx
-	andl $0x0F, %ebx
-	subl %ebx, %esp
+	movl %esp, %ebp
+	andl $-16, %esp
 
 	subl $12, %esp
 	pushl %edi
@@ -26,7 +25,7 @@ signal_trampoline:
 	addl $16, %esp
 
 	// restore stack
-	addl %ebx, %esp
+	movl %ebp, %esp
 	popa
 
 	leave
diff --git a/kernel/arch/x86_64/Signal.S b/kernel/arch/x86_64/Signal.S
index e11a7adb..c3259a68 100644
--- a/kernel/arch/x86_64/Signal.S
+++ b/kernel/arch/x86_64/Signal.S
@@ -27,14 +27,13 @@ signal_trampoline:
 	movq 120(%rsp), %rax
 
 	// align stack to 16 bytes
-	movq %rsp, %rbx
-	andq $0x0F, %rbx
-	subq %rbx, %rsp
+	movq %rsp, %rbp
+	andq $-16, %rsp
 
 	call *%rax
 
 	// restore stack
-	addq %rbx, %rsp
+	movq %rbp, %rsp
 	popq %r15
 	popq %r14
 	popq %r13