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author | David Chase <drchase@google.com> | 2016-03-11 00:10:52 -0500 |
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committer | David Chase <drchase@google.com> | 2016-03-28 16:29:59 +0000 |
commit | 8eec2bbfbc4f209950f677906c6ce67e01d32930 (patch) | |
tree | d7262de9875b76be2e91785823375865b230324c /test/intrinsic.dir | |
parent | 2e90192b0e774f44a2d918509e0bd32823ce5c2c (diff) | |
download | go-8eec2bbfbc4f209950f677906c6ce67e01d32930.tar.gz go-8eec2bbfbc4f209950f677906c6ce67e01d32930.zip |
cmd/compile: added some intrinsics to SSA back end
One intrinsic was needed to help get the very best
performance out of a future GC; as long as that one was
being added, I also added Bswap since that is sometimes
a handy thing to have. I had intended to fill out the
bit-scan intrinsic family, but the mismatch between the
"scan forward" instruction and "count leading zeroes"
was large enough to cause me to leave it out -- it poses
a dilemma that I'd rather dodge right now.
These intrinsics are not exposed for general use.
That's a separate issue requiring an API proposal change
( https://github.com/golang/proposal )
All intrinsics are tested, both that they are substituted
on the appropriate architecture, and that they produce the
expected result.
Change-Id: I5848037cfd97de4f75bdc33bdd89bba00af4a8ee
Reviewed-on: https://go-review.googlesource.com/20564
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Diffstat (limited to 'test/intrinsic.dir')
-rw-r--r-- | test/intrinsic.dir/main.go | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/test/intrinsic.dir/main.go b/test/intrinsic.dir/main.go new file mode 100644 index 0000000000..46e6cb3283 --- /dev/null +++ b/test/intrinsic.dir/main.go @@ -0,0 +1,109 @@ +// Copyright 2016 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. + +package main + +import ( + "fmt" + T "runtime/internal/sys" +) + +var A = []uint64{0x0102030405060708, 0x1122334455667788} +var B = []uint64{0x0807060504030201, 0x8877665544332211} + +var errors int + +func logf(f string, args ...interface{}) { + errors++ + fmt.Printf(f, args...) + if errors > 100 { // 100 is enough spewage + panic("100 errors is plenty is enough") + } +} + +func test(i, x uint64) { + t := T.Ctz64(x) // ERROR "intrinsic substitution for Ctz64" + if i != t { + logf("Ctz64(0x%x) expected %d but got %d\n", x, i, t) + } + x = -x + t = T.Ctz64(x) // ERROR "intrinsic substitution for Ctz64" + if i != t { + logf("Ctz64(0x%x) expected %d but got %d\n", x, i, t) + } + + if i <= 32 { + x32 := uint32(x) + t32 := T.Ctz32(x32) // ERROR "intrinsic substitution for Ctz32" + if uint32(i) != t32 { + logf("Ctz32(0x%x) expected %d but got %d\n", x32, i, t32) + } + x32 = -x32 + t32 = T.Ctz32(x32) // ERROR "intrinsic substitution for Ctz32" + if uint32(i) != t32 { + logf("Ctz32(0x%x) expected %d but got %d\n", x32, i, t32) + } + } + if i <= 16 { + x16 := uint16(x) + t16 := T.Ctz16(x16) // ERROR "intrinsic substitution for Ctz16" + if uint16(i) != t16 { + logf("Ctz16(0x%x) expected %d but got %d\n", x16, i, t16) + } + x16 = -x16 + t16 = T.Ctz16(x16) // ERROR "intrinsic substitution for Ctz16" + if uint16(i) != t16 { + logf("Ctz16(0x%x) expected %d but got %d\n", x16, i, t16) + } + } +} + +func main() { + // Test Bswap first because the other test relies on it + // working correctly (to implement bit reversal). + for i := range A { + x := A[i] + y := B[i] + X := T.Bswap64(x) // ERROR "intrinsic substitution for Bswap64" + Y := T.Bswap64(y) // ERROR "intrinsic substitution for Bswap64" + if y != X { + logf("Bswap64(0x%08x) expected 0x%08x but got 0x%08x\n", x, y, X) + } + if x != Y { + logf("Bswap64(0x%08x) expected 0x%08x but got 0x%08x\n", y, x, Y) + } + + x32 := uint32(X) + y32 := uint32(Y >> 32) + + X32 := T.Bswap32(x32) // ERROR "intrinsic substitution for Bswap32" + Y32 := T.Bswap32(y32) // ERROR "intrinsic substitution for Bswap32" + if y32 != X32 { + logf("Bswap32(0x%08x) expected 0x%08x but got 0x%08x\n", x32, y32, X32) + } + if x32 != Y32 { + logf("Bswap32(0x%08x) expected 0x%08x but got 0x%08x\n", y32, x32, Y32) + } + } + + // Zero is a special case, be sure it is done right. + if T.Ctz16(0) != 16 { // ERROR "intrinsic substitution for Ctz16" + logf("ctz16(0) != 16") + } + if T.Ctz32(0) != 32 { // ERROR "intrinsic substitution for Ctz32" + logf("ctz32(0) != 32") + } + if T.Ctz64(0) != 64 { // ERROR "intrinsic substitution for Ctz64" + logf("ctz64(0) != 64") + } + + for i := uint64(0); i <= 64; i++ { + for j := uint64(1); j <= 255; j += 2 { + for k := uint64(1); k <= 65537; k += 128 { + x := (j * k) << i + test(i, x) + } + } + } +} |