runtime: improve StackCopy benchmarks

Make the StackCopyNoCache test easier to read.

Add a StackCopyPtr test that actually has some pointers
that need adjusting.

Change-Id: I5b07c26f40cb485c9de97ed63fac89a9e6f36650
Reviewed-on: https://go-review.googlesource.com/104195
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

diff --git a/src/runtime/stack_test.go b/src/runtime/stack_test.go
index 0fed241704fb79e23587a1f088fb6a4d546f072f..8342724d0b108a6a89be74d3d0d2e08706c83d76 100644 (file)
--- a/src/runtime/stack_test.go
+++ b/src/runtime/stack_test.go
@@ -452,6 +452,26 @@ func TestStackPanic(t *testing.T) {
        panic("test panic")
 }
 
+func BenchmarkStackCopyPtr(b *testing.B) {
+       c := make(chan bool)
+       for i := 0; i < b.N; i++ {
+               go func() {
+                       i := 1000000
+                       countp(&i)
+                       c <- true
+               }()
+               <-c
+       }
+}
+
+func countp(n *int) {
+       if *n == 0 {
+               return
+       }
+       *n--
+       countp(n)
+}
+
 func BenchmarkStackCopy(b *testing.B) {
        c := make(chan bool)
        for i := 0; i < b.N; i++ {
@@ -482,165 +502,34 @@ func BenchmarkStackCopyNoCache(b *testing.B) {
 }
 
 func count1(n int) int {
-       if n == 0 {
+       if n <= 0 {
                return 0
        }
        return 1 + count2(n-1)
 }
 
-func count2(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count3(n-1)
-}
-
-func count3(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count4(n-1)
-}
-
-func count4(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count5(n-1)
-}
-
-func count5(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count6(n-1)
-}
-
-func count6(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count7(n-1)
-}
-
-func count7(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count8(n-1)
-}
-
-func count8(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count9(n-1)
-}
-
-func count9(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count10(n-1)
-}
-
-func count10(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count11(n-1)
-}
-
-func count11(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count12(n-1)
-}
-
-func count12(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count13(n-1)
-}
-
-func count13(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count14(n-1)
-}
-
-func count14(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count15(n-1)
-}
-
-func count15(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count16(n-1)
-}
-
-func count16(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count17(n-1)
-}
-
-func count17(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count18(n-1)
-}
-
-func count18(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count19(n-1)
-}
-
-func count19(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count20(n-1)
-}
-
-func count20(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count21(n-1)
-}
-
-func count21(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count22(n-1)
-}
-
-func count22(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count23(n-1)
-}
-
-func count23(n int) int {
-       if n == 0 {
-               return 0
-       }
-       return 1 + count1(n-1)
-}
+func count2(n int) int  { return 1 + count3(n-1) }
+func count3(n int) int  { return 1 + count4(n-1) }
+func count4(n int) int  { return 1 + count5(n-1) }
+func count5(n int) int  { return 1 + count6(n-1) }
+func count6(n int) int  { return 1 + count7(n-1) }
+func count7(n int) int  { return 1 + count8(n-1) }
+func count8(n int) int  { return 1 + count9(n-1) }
+func count9(n int) int  { return 1 + count10(n-1) }
+func count10(n int) int { return 1 + count11(n-1) }
+func count11(n int) int { return 1 + count12(n-1) }
+func count12(n int) int { return 1 + count13(n-1) }
+func count13(n int) int { return 1 + count14(n-1) }
+func count14(n int) int { return 1 + count15(n-1) }
+func count15(n int) int { return 1 + count16(n-1) }
+func count16(n int) int { return 1 + count17(n-1) }
+func count17(n int) int { return 1 + count18(n-1) }
+func count18(n int) int { return 1 + count19(n-1) }
+func count19(n int) int { return 1 + count20(n-1) }
+func count20(n int) int { return 1 + count21(n-1) }
+func count21(n int) int { return 1 + count22(n-1) }
+func count22(n int) int { return 1 + count23(n-1) }
+func count23(n int) int { return 1 + count1(n-1) }
 
 type structWithMethod struct{}