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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:18:25 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:18:25 +0000
commit109be507377fe7f6e8819ac94041d3fdcdf6fd2f (patch)
tree2806a689f8fab4a2ec9fc949830ef270a91d667d /test/mergemul.go
parentInitial commit. (diff)
downloadgolang-1.19-109be507377fe7f6e8819ac94041d3fdcdf6fd2f.tar.xz
golang-1.19-109be507377fe7f6e8819ac94041d3fdcdf6fd2f.zip
Adding upstream version 1.19.8.upstream/1.19.8upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'test/mergemul.go')
-rw-r--r--test/mergemul.go117
1 files changed, 117 insertions, 0 deletions
diff --git a/test/mergemul.go b/test/mergemul.go
new file mode 100644
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--- /dev/null
+++ b/test/mergemul.go
@@ -0,0 +1,117 @@
+// runoutput
+
+// Copyright 2017 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"
+
+// Check that expressions like (c*n + d*(n+k)) get correctly merged by
+// the compiler into (c+d)*n + d*k (with c+d and d*k computed at
+// compile time).
+//
+// The merging is performed by a combination of the multiplication
+// merge rules
+// (c*n + d*n) -> (c+d)*n
+// and the distributive multiplication rules
+// c * (d+x) -> c*d + c*x
+
+// Generate a MergeTest that looks like this:
+//
+// a8, b8 = m1*n8 + m2*(n8+k), (m1+m2)*n8 + m2*k
+// if a8 != b8 {
+// // print error msg and panic
+// }
+func makeMergeAddTest(m1, m2, k int, size string) string {
+
+ model := " a" + size + ", b" + size
+ model += fmt.Sprintf(" = %%d*n%s + %%d*(n%s+%%d), (%%d+%%d)*n%s + (%%d*%%d)", size, size, size)
+
+ test := fmt.Sprintf(model, m1, m2, k, m1, m2, m2, k)
+ test += fmt.Sprintf(`
+ if a%s != b%s {
+ fmt.Printf("MergeAddTest(%d, %d, %d, %s) failed\n")
+ fmt.Printf("%%d != %%d\n", a%s, b%s)
+ panic("FAIL")
+ }
+`, size, size, m1, m2, k, size, size, size)
+ return test + "\n"
+}
+
+// Check that expressions like (c*n - d*(n+k)) get correctly merged by
+// the compiler into (c-d)*n - d*k (with c-d and d*k computed at
+// compile time).
+//
+// The merging is performed by a combination of the multiplication
+// merge rules
+// (c*n - d*n) -> (c-d)*n
+// and the distributive multiplication rules
+// c * (d-x) -> c*d - c*x
+
+// Generate a MergeTest that looks like this:
+//
+// a8, b8 = m1*n8 - m2*(n8+k), (m1-m2)*n8 - m2*k
+// if a8 != b8 {
+// // print error msg and panic
+// }
+func makeMergeSubTest(m1, m2, k int, size string) string {
+
+ model := " a" + size + ", b" + size
+ model += fmt.Sprintf(" = %%d*n%s - %%d*(n%s+%%d), (%%d-%%d)*n%s - (%%d*%%d)", size, size, size)
+
+ test := fmt.Sprintf(model, m1, m2, k, m1, m2, m2, k)
+ test += fmt.Sprintf(`
+ if a%s != b%s {
+ fmt.Printf("MergeSubTest(%d, %d, %d, %s) failed\n")
+ fmt.Printf("%%d != %%d\n", a%s, b%s)
+ panic("FAIL")
+ }
+`, size, size, m1, m2, k, size, size, size)
+ return test + "\n"
+}
+
+func makeAllSizes(m1, m2, k int) string {
+ var tests string
+ tests += makeMergeAddTest(m1, m2, k, "8")
+ tests += makeMergeAddTest(m1, m2, k, "16")
+ tests += makeMergeAddTest(m1, m2, k, "32")
+ tests += makeMergeAddTest(m1, m2, k, "64")
+ tests += makeMergeSubTest(m1, m2, k, "8")
+ tests += makeMergeSubTest(m1, m2, k, "16")
+ tests += makeMergeSubTest(m1, m2, k, "32")
+ tests += makeMergeSubTest(m1, m2, k, "64")
+ tests += "\n"
+ return tests
+}
+
+func main() {
+ fmt.Println(`package main
+
+import "fmt"
+
+var n8 int8 = 42
+var n16 int16 = 42
+var n32 int32 = 42
+var n64 int64 = 42
+
+func main() {
+ var a8, b8 int8
+ var a16, b16 int16
+ var a32, b32 int32
+ var a64, b64 int64
+`)
+
+ fmt.Println(makeAllSizes(03, 05, 0)) // 3*n + 5*n
+ fmt.Println(makeAllSizes(17, 33, 0))
+ fmt.Println(makeAllSizes(80, 45, 0))
+ fmt.Println(makeAllSizes(32, 64, 0))
+
+ fmt.Println(makeAllSizes(7, 11, +1)) // 7*n + 11*(n+1)
+ fmt.Println(makeAllSizes(9, 13, +2))
+ fmt.Println(makeAllSizes(11, 16, -1))
+ fmt.Println(makeAllSizes(17, 9, -2))
+
+ fmt.Println("}")
+}