[dev.power64] code review 160200044: build: merge default into dev.power64

src/cmd/gc/racewalk.c

 // Copyright 2012 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 // The racewalk pass modifies the code tree for the function as follows:
 //
 // 1. It inserts a call to racefuncenter at the beginning of each function.
 // 2. It inserts a call to racefuncexit at the end of each function.
 // 3. It inserts a call to raceread before each memory read.
 // 4. It inserts a call to racewrite before each memory write.
@@ skipping 401 matching lines @@
         case ONONAME:
         case OLITERAL:
         case OSLICESTR:  // always preceded by bounds checking, avoid double instrumentation.
         case OTYPESW:    // ignored by code generation, do not instrument.
                 goto ret;
         }
 
 ret:
         if(n->op != OBLOCK)  // OBLOCK is handled above in a special way.
                 racewalklist(n->list, init);
-        racewalknode(&n->ntest, &n->ntest->ninit, 0, 0);
-        racewalknode(&n->nincr, &n->nincr->ninit, 0, 0);
+        if(n->ntest != N)
+                racewalknode(&n->ntest, &n->ntest->ninit, 0, 0);
+        if(n->nincr != N)
+                racewalknode(&n->nincr, &n->nincr->ninit, 0, 0);
         racewalklist(n->nbody, nil);
         racewalklist(n->nelse, nil);
         racewalklist(n->rlist, nil);
         *np = n;
 }
 
 static int
 isartificial(Node *n)
 {
         // compiler-emitted artificial things that we do not want to instrument,
@@ skipping 199 matching lines @@
                 n = nod(OCONVNOP, n, N);
                 n->type = n->left->type;
                 n->typecheck = 1;
                 *np = n;
                 break;
         }
         n->ninit = concat(n->ninit, init);
         n->ullman = UINF;
 }