fix mips clone() on real linux kernel
the old code worked in qemu app-level emulation, but not on real
kernels where the clone syscall does not copy the register values to
the new thread. save arguments on the new thread stack instead.
diff --git a/src/thread/mips/clone.s b/src/thread/mips/clone.s
index a7c2d90..fab90dc 100644
--- a/src/thread/mips/clone.s
+++ b/src/thread/mips/clone.s
@@ -2,9 +2,10 @@
.global __clone
.type __clone,@function
__clone:
- # Save function pointer and argument pointer
- move $25, $4
- move $8, $7
+ # Save function pointer and argument pointer on new thread stack
+ subu $5, $5, 16
+ sw $4, 0($5)
+ sw $7, 4($5)
# Shuffle (fn,sp,fl,arg,ptid,tls,ctid) to (fl,sp,ptid,tls,ctid)
move $4, $6
lw $6, 16($sp)
@@ -21,6 +22,8 @@
nop
jr $ra
nop
-1: move $4, $8
+1: lw $25, 0($sp)
+ lw $4, 4($sp)
jr $25
+ addu $sp, $sp, 16
nop
