diff options
| author | Andrew Gerrand <adg@golang.org> | 2014-08-12 10:05:20 +1000 |
|---|---|---|
| committer | Andrew Gerrand <adg@golang.org> | 2014-08-12 10:05:20 +1000 |
| commit | 2cfe73640f401087e735f08e19ecb0ac524ec910 (patch) | |
| tree | 60a322de136fcaa03b011cfbf54dfe98f92a9493 | |
| parent | 0938cdf95f14d9223ee9980843286dde3313a163 (diff) | |
| download | go-2cfe73640f401087e735f08e19ecb0ac524ec910.tar.gz | |
[release-branch.go1.3] cmd/6g, cmd/8g: fix, test byte-sized magic multiply
??? CL 124950043 / 8e5ec6948793
cmd/6g, cmd/8g: fix, test byte-sized magic multiply
Credit to R?my for finding and writing test case.
Fixes issue 8325.
LGTM=r
R=golang-codereviews, r
CC=dave, golang-codereviews, iant, remyoudompheng
https://codereview.appspot.com/124950043
???
TBR=rsc
CC=golang-codereviews
https://codereview.appspot.com/126000043
| -rw-r--r-- | src/cmd/6g/ggen.c | 2 | ||||
| -rw-r--r-- | src/cmd/6g/peep.c | 5 | ||||
| -rw-r--r-- | src/cmd/8g/ggen.c | 2 | ||||
| -rw-r--r-- | src/cmd/8g/peep.c | 5 | ||||
| -rw-r--r-- | test/fixedbugs/issue8325.go | 31 |
5 files changed, 43 insertions, 2 deletions
diff --git a/src/cmd/6g/ggen.c b/src/cmd/6g/ggen.c index c385798f2..9665d831b 100644 --- a/src/cmd/6g/ggen.c +++ b/src/cmd/6g/ggen.c @@ -943,7 +943,7 @@ cgen_hmul(Node *nl, Node *nr, Node *res) if(t->width == 1) { // byte multiply behaves differently. nodreg(&ax, t, D_AH); - nodreg(&dx, t, D_DL); + nodreg(&dx, t, D_DX); gmove(&ax, &dx); } nodreg(&dx, t, D_DX); diff --git a/src/cmd/6g/peep.c b/src/cmd/6g/peep.c index 0f2720443..24617836f 100644 --- a/src/cmd/6g/peep.c +++ b/src/cmd/6g/peep.c @@ -838,6 +838,11 @@ copyu(Prog *p, Adr *v, Adr *s) static int copyas(Adr *a, Adr *v) { + if(D_AL <= a->type && a->type <= D_R15B) + fatal("use of byte register"); + if(D_AL <= v->type && v->type <= D_R15B) + fatal("use of byte register"); + if(a->type != v->type) return 0; if(regtyp(v)) diff --git a/src/cmd/8g/ggen.c b/src/cmd/8g/ggen.c index 2285a04e6..5e3140480 100644 --- a/src/cmd/8g/ggen.c +++ b/src/cmd/8g/ggen.c @@ -991,7 +991,7 @@ cgen_hmul(Node *nl, Node *nr, Node *res) if(t->width == 1) { // byte multiply behaves differently. nodreg(&ax, t, D_AH); - nodreg(&dx, t, D_DL); + nodreg(&dx, t, D_DX); gmove(&ax, &dx); } nodreg(&dx, t, D_DX); diff --git a/src/cmd/8g/peep.c b/src/cmd/8g/peep.c index a4e516dd3..f902674ec 100644 --- a/src/cmd/8g/peep.c +++ b/src/cmd/8g/peep.c @@ -634,6 +634,11 @@ copyu(Prog *p, Adr *v, Adr *s) static int copyas(Adr *a, Adr *v) { + if(D_AL <= a->type && a->type <= D_R15B) + fatal("use of byte register"); + if(D_AL <= v->type && v->type <= D_R15B) + fatal("use of byte register"); + if(a->type != v->type) return 0; if(regtyp(v)) diff --git a/test/fixedbugs/issue8325.go b/test/fixedbugs/issue8325.go new file mode 100644 index 000000000..e22fd319d --- /dev/null +++ b/test/fixedbugs/issue8325.go @@ -0,0 +1,31 @@ +// run + +// Copyright 2014 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. + +// Issue 8325: corrupted byte operations during optimization +// pass. + +package main + +const alphanum = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" + +func main() { + var bytes = []byte{10, 20, 30, 40, 50} + + for i, b := range bytes { + bytes[i] = alphanum[b%byte(len(alphanum))] + } + + for _, b := range bytes { + switch { + case '0' <= b && b <= '9', + 'A' <= b && b <= 'Z': + default: + println("found a bad character", string(b)) + panic("BUG") + } + + } +} |