cmd/8g: add a few missing splitclean

Fixes #887.

R=ken2
CC=golang-dev
https://golang.org/cl/7303061

diff --git a/src/cmd/8g/ggen.c b/src/cmd/8g/ggen.c
index 2921853f2d88b38b3872d2dbb7df19cccc0182f5..465177f1369e24af7e6d5c4980c6859e4b0d4ba2 100644 (file)
--- a/src/cmd/8g/ggen.c
+++ b/src/cmd/8g/ggen.c
@@ -704,6 +704,7 @@ cgen_shift(int op, int bounded, Node *nl, Node *nr, Node *res)
                        regalloc(&n1, types[TUINT32], &n1);             // to hold the shift type in CX
                        split64(&nt, &lo, &hi);
                        gmove(&lo, &n1);
+                       splitclean();
                }
        } else {
                if(nr->type->width > 4) {
@@ -716,6 +717,7 @@ cgen_shift(int op, int bounded, Node *nl, Node *nr, Node *res)
                        p2 = gbranch(optoas(ONE, types[TUINT32]), T, +1);
                        gins(optoas(OCMP, types[TUINT32]), &n1, ncon(w));
                        p1 = gbranch(optoas(OLT, types[TUINT32]), T, +1);
+                       splitclean();
                        patch(p2, pc);
                } else {
                        gins(optoas(OCMP, nr->type), &n1, ncon(w));

diff --git a/src/cmd/8g/gsubr.c b/src/cmd/8g/gsubr.c
index 4c86b7582eb5561418971e6f6bbaf7786dedff39..c21c2022ed5c982ace504393aecee330ca139513 100644 (file)
--- a/src/cmd/8g/gsubr.c
+++ b/src/cmd/8g/gsubr.c
@@ -1168,9 +1168,9 @@ split64(Node *n, Node *lo, Node *hi)
        if(!is64(n->type))
                fatal("split64 %T", n->type);
 
-       sclean[nsclean].op = OEMPTY;
        if(nsclean >= nelem(sclean))
                fatal("split64 clean");
+       sclean[nsclean].op = OEMPTY;
        nsclean++;
        switch(n->op) {
        default:

diff --git a/test/fixedbugs/issue887.go b/test/fixedbugs/issue887.go
new file mode 100644 (file)
index 0000000..5bc193b
--- /dev/null
+++ b/test/fixedbugs/issue887.go
@@ -0,0 +1,36 @@
+// compile
+
+// Copyright 2013 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.
+
+// Used to leak registers on 8g.
+
+package p
+
+func f(x byte, y uint64) {
+       var r byte
+       switch y {
+       case 1:
+               r = x << y // '>>' triggers it too
+       case 2:
+               r = x << y
+       case 3:
+               r = x << y
+       case 4:
+               r = x << y
+       case 5:
+               r = x << y
+       case 6:
+               r = x << y
+       case 7:
+               r = x << y
+       case 8:
+               r = x << y
+       case 9:
+               r = x << y
+       case 10:
+               r = x << y
+       }
+       _ = r
+}