Remove unnecessary test for switching from null current thread.

[pintos-anon] / src / threads / switch.S

diff --git a/src/threads/switch.S b/src/threads/switch.S
index 374da9e4a11cfd64a79816c3d358a177b224ff09..48fc588973bfe15c016dab042bc75f37c6baba62 100644 (file)
--- a/src/threads/switch.S
+++ b/src/threads/switch.S
@@ -12,7 +12,8 @@
 #### restore the registers.  As part of switching stacks we record the
 #### current stack pointer in CUR's thread structure.
 
-.globl switch_threads 
+.globl switch_threads
+.func switch_threads
 switch_threads:
        # Save caller's register state.
        #
@@ -32,10 +33,7 @@ switch_threads:
 
        # Save current stack pointer to old thread's stack, if any.
        movl SWITCH_CUR(%esp), %eax
-       test %eax, %eax
-       jz 1f
        movl %esp, (%eax,%edx,1)
-1:
 
        # Restore stack pointer from new thread's stack.
        movl SWITCH_NEXT(%esp), %ecx
@@ -47,8 +45,10 @@ switch_threads:
        popl %ebp
        popl %ebx
         ret
+.endfunc
 
 .globl switch_entry
+.func switch_entry
 switch_entry:
        # Discard switch_threads() arguments.
        addl $8, %esp
@@ -61,3 +61,4 @@ switch_entry:
 
        # Start thread proper.
        ret
+.endfunc