hash/crc32: fix nil Castagnoli table problem
When SSE is available, we don't need the Table. However, it is
returned as a handle by MakeTable. Fix this to always generate
the table.
Further cleanup is discussed in #16909.
Change-Id: Ic05400d68c6b5d25073ebd962000451746137afc
Reviewed-on: https://go-review.googlesource.com/27934
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/hash/crc32/crc32.go b/src/hash/crc32/crc32.go
index 57089a7..6eed8ff 100644
--- a/src/hash/crc32/crc32.go
+++ b/src/hash/crc32/crc32.go
@@ -57,9 +57,12 @@
needGenericTables := castagnoliInitArch()
if needGenericTables {
- castagnoliTable = makeTable(Castagnoli)
castagnoliTable8 = makeTable8(Castagnoli)
}
+
+ // Even if we don't need the contents of this table, we use it as a handle
+ // returned by MakeTable. We should find a way to clean this up (see #16909).
+ castagnoliTable = makeTable(Castagnoli)
}
// IEEETable is the table for the IEEE polynomial.
diff --git a/src/hash/crc32/crc32_amd64_test.go b/src/hash/crc32/crc32_amd64_test.go
index 8bbaa10..e136f78 100644
--- a/src/hash/crc32/crc32_amd64_test.go
+++ b/src/hash/crc32/crc32_amd64_test.go
@@ -15,11 +15,10 @@
}
// Init the SSE42 tables.
- MakeTable(Castagnoli)
+ castagnoliOnce.Do(castagnoliInit)
- // Manually init the software implementation to compare against.
- castagnoliTable = makeTable(Castagnoli)
- castagnoliTable8 = makeTable8(Castagnoli)
+ // Generate a table to use with the non-SSE version.
+ slicingTable := makeTable8(Castagnoli)
// The optimized SSE4.2 implementation behaves differently for different
// lengths (especially around multiples of K*3). Crosscheck against the
@@ -32,7 +31,7 @@
p := make([]byte, length)
_, _ = rand.Read(p)
crcInit := uint32(rand.Int63())
- correct := updateSlicingBy8(crcInit, castagnoliTable8, p)
+ correct := updateSlicingBy8(crcInit, slicingTable, p)
result := updateCastagnoli(crcInit, p)
if result != correct {
t.Errorf("SSE42 implementation = 0x%x want 0x%x (buffer length %d)",
diff --git a/src/hash/crc32/crc32_test.go b/src/hash/crc32/crc32_test.go
index 113a109..7f7f0a2 100644
--- a/src/hash/crc32/crc32_test.go
+++ b/src/hash/crc32/crc32_test.go
@@ -51,6 +51,9 @@
func TestGolden(t *testing.T) {
castagnoliTab := MakeTable(Castagnoli)
+ if castagnoliTab == nil {
+ t.Errorf("nil Castagnoli Table")
+ }
for _, g := range golden {
ieee := NewIEEE()
