cmd/compile: mark ARM's CALLudiv not safepoint

ARM's udiv function is nosplit and it shouldn't be preemptied
(passing args in registers). It is in some sense like DUFFCOPY,
which we don't mark as safepoint.

Change-Id: I49f7c4e69e787ac364d0b0def0661e79a0ea9e69
Reviewed-on: https://go-review.googlesource.com/41370
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>

diff --git a/src/cmd/compile/internal/arm/ssa.go b/src/cmd/compile/internal/arm/ssa.go
index 8faaf0ffb8e0c56a1f971227bf73e06508d3a439..ea9c3a9cc1ce2be7cc3c1e06fa0e07e5af97f7c2 100644 (file)
--- a/src/cmd/compile/internal/arm/ssa.go
+++ b/src/cmd/compile/internal/arm/ssa.go
@@ -625,8 +625,10 @@ func ssaGenValue(s *gc.SSAGenState, v *ssa.Value) {
        case ssa.OpARMCALLstatic, ssa.OpARMCALLclosure, ssa.OpARMCALLinter:
                s.Call(v)
        case ssa.OpARMCALLudiv:
-               v.Aux = gc.Udiv
-               s.Call(v)
+               p := s.Prog(obj.ACALL)
+               p.To.Type = obj.TYPE_MEM
+               p.To.Name = obj.NAME_EXTERN
+               p.To.Sym = gc.Udiv
        case ssa.OpARMDUFFZERO:
                p := s.Prog(obj.ADUFFZERO)
                p.To.Type = obj.TYPE_MEM

diff --git a/src/cmd/compile/internal/gc/plive.go b/src/cmd/compile/internal/gc/plive.go
index 4525426d4f31c7255d53ebf882eeb305a90a31a4..96fbb327f283818916524959e46506df7ef80b03 100644 (file)
--- a/src/cmd/compile/internal/gc/plive.go
+++ b/src/cmd/compile/internal/gc/plive.go
@@ -502,7 +502,7 @@ func onebitlivepointermap(lv *Liveness, liveout bvec, vars []*Node, args bvec, l
 // Returns true for instructions that are safe points that must be annotated
 // with liveness information.
 func issafepoint(v *ssa.Value) bool {
-       return v.Op.IsCall() || v.Op == ssa.OpARMCALLudiv
+       return v.Op.IsCall()
 }
 
 // Initializes the sets for solving the live variables. Visits all the