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authorRobert Morris <[email protected]>2019-06-11 09:57:14 -0400
committerRobert Morris <[email protected]>2019-06-11 09:57:14 -0400
commit5753553213df8f9de851adb68377db43faecb91f (patch)
tree3b629ff54897fca414146677532cb459a2ed11ba /kernel/swtch.S
parent91ba81110acd3163f7de3580b677eece0c57f5e7 (diff)
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separate source into kernel/ user/ mkfs/
Diffstat (limited to 'kernel/swtch.S')
-rw-r--r--kernel/swtch.S42
1 files changed, 42 insertions, 0 deletions
diff --git a/kernel/swtch.S b/kernel/swtch.S
new file mode 100644
index 0000000..17a8663
--- /dev/null
+++ b/kernel/swtch.S
@@ -0,0 +1,42 @@
+# Context switch
+#
+# void swtch(struct context *old, struct context *new);
+#
+# Save current registers in old. Load from new.
+
+
+.globl swtch
+swtch:
+ sd ra, 0(a0)
+ sd sp, 8(a0)
+ sd s0, 16(a0)
+ sd s1, 24(a0)
+ sd s2, 32(a0)
+ sd s3, 40(a0)
+ sd s4, 48(a0)
+ sd s5, 56(a0)
+ sd s6, 64(a0)
+ sd s7, 72(a0)
+ sd s8, 80(a0)
+ sd s9, 88(a0)
+ sd s10, 96(a0)
+ sd s11, 104(a0)
+
+ ld ra, 0(a1)
+ ld sp, 8(a1)
+ ld s0, 16(a1)
+ ld s1, 24(a1)
+ ld s2, 32(a1)
+ ld s3, 40(a1)
+ ld s4, 48(a1)
+ ld s5, 56(a1)
+ ld s6, 64(a1)
+ ld s7, 72(a1)
+ ld s8, 80(a1)
+ ld s9, 88(a1)
+ ld s10, 96(a1)
+ ld s11, 104(a1)
+
+ ret
+
+