[dev.cc] all: merge dev.power64 (7667e41f3ced) into dev.cc

This is to reduce the delta between dev.cc and dev.garbage to just garbage collector changes.

These are the files that had merge conflicts and have been edited by hand:
        malloc.go
        mem_linux.go
        mgc.go
        os1_linux.go
        proc1.go
        panic1.go
        runtime1.go

LGTM=austin
R=austin
CC=golang-codereviews
https://codereview.appspot.com/174180043

1 files changed, 27 insertions, 33 deletions

diff --git a/src/runtime/asm_arm.s b/src/runtime/asm_arm.s
index 58aebf388..583c7ba50 100644
--- a/src/runtime/asm_arm.s
+++ b/src/runtime/asm_arm.s
@@ -2,7 +2,8 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-#include "zasm_GOOS_GOARCH.h"
+#include "go_asm.h"
+#include "go_tls.h"
 #include "funcdata.h"
 #include "textflag.h"
 
@@ -54,7 +55,7 @@ TEXT runtime·rt0_go(SB),NOSPLIT,$-4
 nocgo:
 	// update stackguard after _cgo_init
 	MOVW	(g_stack+stack_lo)(g), R0
-	ADD	$const_StackGuard, R0
+	ADD	$const__StackGuard, R0
 	MOVW	R0, g_stackguard0(g)
 	MOVW	R0, g_stackguard1(g)
 
@@ -190,53 +191,42 @@ TEXT runtime·mcall(SB),NOSPLIT,$-4-4
 	B	runtime·badmcall2(SB)
 	RET
 
-// switchtoM is a dummy routine that onM leaves at the bottom
+// systemstack_switch is a dummy routine that systemstack leaves at the bottom
 // of the G stack.  We need to distinguish the routine that
 // lives at the bottom of the G stack from the one that lives
-// at the top of the M stack because the one at the top of
-// the M stack terminates the stack walk (see topofstack()).
-TEXT runtime·switchtoM(SB),NOSPLIT,$0-0
+// at the top of the system stack because the one at the top of
+// the system stack terminates the stack walk (see topofstack()).
+TEXT runtime·systemstack_switch(SB),NOSPLIT,$0-0
 	MOVW	$0, R0
 	BL	(R0) // clobber lr to ensure push {lr} is kept
 	RET
 
-// func onM_signalok(fn func())
-TEXT runtime·onM_signalok(SB), NOSPLIT, $-4-4
-	MOVW	g_m(g), R1
-	MOVW	m_gsignal(R1), R2
-	CMP	g, R2
-	B.EQ	ongsignal
-	B	runtime·onM(SB)
-
-ongsignal:
-	MOVW	fn+0(FP), R0
-	MOVW	R0, R7
-	MOVW	0(R0), R0
-	BL	(R0)
-	RET
-
-// func onM(fn func())
-TEXT runtime·onM(SB),NOSPLIT,$0-4
+// func systemstack(fn func())
+TEXT runtime·systemstack(SB),NOSPLIT,$0-4
 	MOVW	fn+0(FP), R0	// R0 = fn
 	MOVW	g_m(g), R1	// R1 = m
 
+	MOVW	m_gsignal(R1), R2	// R2 = gsignal
+	CMP	g, R2
+	B.EQ	noswitch
+
 	MOVW	m_g0(R1), R2	// R2 = g0
 	CMP	g, R2
-	B.EQ	onm
+	B.EQ	noswitch
 
 	MOVW	m_curg(R1), R3
 	CMP	g, R3
-	B.EQ	oncurg
+	B.EQ	switch
 
-	// Not g0, not curg. Must be gsignal, but that's not allowed.
+	// Bad: g is not gsignal, not g0, not curg. What is it?
 	// Hide call from linker nosplit analysis.
-	MOVW	$runtime·badonm(SB), R0
+	MOVW	$runtime·badsystemstack(SB), R0
 	BL	(R0)
 
-oncurg:
+switch:
 	// save our state in g->sched.  Pretend to
-	// be switchtoM if the G stack is scanned.
-	MOVW	$runtime·switchtoM(SB), R3
+	// be systemstack_switch if the G stack is scanned.
+	MOVW	$runtime·systemstack_switch(SB), R3
 	ADD	$4, R3, R3 // get past push {lr}
 	MOVW	R3, (g_sched+gobuf_pc)(g)
 	MOVW	SP, (g_sched+gobuf_sp)(g)
@@ -249,7 +239,7 @@ oncurg:
 	BL	setg<>(SB)
 	MOVW	R5, R0
 	MOVW	(g_sched+gobuf_sp)(R2), R3
-	// make it look like mstart called onM on g0, to stop traceback
+	// make it look like mstart called systemstack on g0, to stop traceback
 	SUB	$4, R3, R3
 	MOVW	$runtime·mstart(SB), R4
 	MOVW	R4, 0(R3)
@@ -269,7 +259,7 @@ oncurg:
 	MOVW	R3, (g_sched+gobuf_sp)(g)
 	RET
 
-onm:
+noswitch:
 	MOVW	R0, R7
 	MOVW	0(R0), R0
 	BL	(R0)
@@ -564,7 +554,7 @@ TEXT	·cgocallback_gofunc(SB),NOSPLIT,$8-12
 	// the same SP back to m->sched.sp. That seems redundant,
 	// but if an unrecovered panic happens, unwindm will
 	// restore the g->sched.sp from the stack location
-	// and then onM will try to use it. If we don't set it here,
+	// and then systemstack will try to use it. If we don't set it here,
 	// that restored SP will be uninitialized (typically 0) and
 	// will not be usable.
 	MOVW	g_m(g), R8
@@ -1326,3 +1316,7 @@ TEXT _cgo_topofstack(SB),NOSPLIT,$8
 TEXT runtime·goexit(SB),NOSPLIT,$-4-0
 	MOVW	R0, R0	// NOP
 	BL	runtime·goexit1(SB)	// does not return
+
+TEXT runtime·getg(SB),NOSPLIT,$-4-4
+	MOVW	g, ret+0(FP)
+	RET