Add Gobuf.r0 that stores arg0 or return value of
goroutine. arm only.
R=rsc
APPROVED=rsc
DELTA=5 (3 added, 2 deleted, 0 changed)
OCL=30644
CL=30746
diff --git a/src/pkg/runtime/arm/asm.s b/src/pkg/runtime/arm/asm.s
index 39ac99e..f709ebb 100644
--- a/src/pkg/runtime/arm/asm.s
+++ b/src/pkg/runtime/arm/asm.s
@@ -111,7 +111,6 @@
// void gogocall(Gobuf*, void (*fn)(void))
// restore state from Gobuf but then call fn.
// (call fn, returning to state in Gobuf)
-// TODO(kaib): add R0 to gobuf so it can be restored properly
// using frame size $-4 means do not save LR on stack.
TEXT gogocall(SB), 7, $-4
MOVW 8(SP), R1 // fn
@@ -119,6 +118,7 @@
MOVW 0(g), R2 // make sure g != nil
MOVW gobuf_sp(R0), SP // restore SP
MOVW gobuf_pc(R0), LR
+ MOVW gobuf_r0(R0), R0
MOVW R1, PC
/*
@@ -146,6 +146,7 @@
MOVW R3, (m_morebuf+gobuf_pc)(m) // f's caller's PC
MOVW SP, (m_morebuf+gobuf_sp)(m) // f's caller's SP
MOVW g, (m_morebuf+gobuf_g)(m)
+ MOVW R0, (m_morebuf+gobuf_r0)(m)
// Set m->morepc to f's PC.
MOVW LR, m_morepc(m)
@@ -172,7 +173,6 @@
// R3 is LR for f (f's caller's PC)
// using frame size $-4 means do not save LR on stack.
TEXT sys·morestackx(SB), 7, $-4
- MOVW R0, 0(FP) // Save arg0
MOVW $0, R1 // set frame size
B sys·morestack(SB)
diff --git a/src/pkg/runtime/runtime.h b/src/pkg/runtime/runtime.h
index 662fde7..d7bf807 100644
--- a/src/pkg/runtime/runtime.h
+++ b/src/pkg/runtime/runtime.h
@@ -138,6 +138,7 @@
byte* sp;
byte* pc;
G* g;
+ uintptr r0; // used on arm
};
struct G
{
