runtime: add tstart_sysvicall

Fixes golang#15.

Change-Id: Ifd91b46b96ba57cb1b23d4caf3257be2a2c49cd5

Author: 4ad

src/runtime/asm_sparc64.s

@@ -699,6 +699,21 @@ TEXT setg_gcc<>(SB),NOSPLIT,$16
 	MOVD	savedRT1-8(SP), RT1
 	RET
 
+// check that SP is in range [g->stack.lo, g->stack.hi)
+TEXT runtime·stackcheck(SB), NOSPLIT, $0
+	MOVD	BSP, R28
+	MOVD	(g_stack+stack_hi)(g), R27
+	CMP	R28, R27
+	BGD	2(PC);
+	UNDEF
+
+	MOVD	(g_stack+stack_lo)(g), R27
+	CMP	R27, R28
+	BGD	2(PC);
+	UNDEF
+
+	RET
+
 TEXT runtime·getcallerpc(SB),NOSPLIT,$16-16
 	MOVD	FIXED_FRAME+8*15(BFP), R25		// LR saved by caller
 	MOVD	runtime·stackBarrierPC(SB), R28

src/runtime/sys_solaris_sparc64.s

@@ -112,16 +112,25 @@ skiperrno2:
 
 // uint32 tstart_sysvicall(M *newm);
 TEXT runtime·tstart_sysvicall(SB),NOSPLIT,$0
-	// TODO(aram):
-	MOVD	$74, R27
-	ADD	$'!', R27, R27
-	MOVB	R27, dbgbuf(SB)
-	MOVD	$2, R8
-	MOVD	$dbgbuf(SB), R9
-	MOVD	$2, R10
-	MOVD	$libc_write(SB), R27
-	CALL	R27
-	UNDEF
+	// I0 contains first arg newm
+	MOVD	m_g0(I0), g		// g
+	MOVD	I0, g_m(g)
+
+	CALL	runtime·save_g(SB)
+
+	// Layout new m scheduler stack on os stack.
+	MOVD	BSP, R27
+	MOVD	R27, (g_stack+stack_hi)(g)
+	SUB	$(0x100000), R27		// stack size
+	MOVD	R27, (g_stack+stack_lo)(g)
+	ADD	$const__StackGuard, R27
+	MOVD	R27, g_stackguard0(g)
+	MOVD	R27, g_stackguard1(g)
+
+	CALL	runtime·stackcheck(SB)
+	CALL	runtime·mstart(SB)
+
+	MOVW	ZR, ret+8(FP)
 	RET
 
 // Careful, this is called by __sighndlr, a libc function. We must preserve