From 980fdb8dd5fe0151a9b7e84ec6b8c20a11727521 Mon Sep 17 00:00:00 2001 From: Giovanni Bajo Date: Mon, 2 Apr 2018 03:17:18 +0200 Subject: [PATCH] cmd/compile: improve testing of induction variables Test both minimum and maximum bound, and prepare formatting for more advanced tests (inclusive / esclusive bounds). Change-Id: Ibe432916d9c938343bc07943798bc9709ad71845 Reviewed-on: https://go-review.googlesource.com/104040 Run-TryBot: Giovanni Bajo TryBot-Result: Gobot Gobot Reviewed-by: Brad Fitzpatrick --- src/cmd/compile/internal/ssa/loopbce.go | 21 ++++++++-- test/loopbce.go | 54 ++++++++++++------------- test/prove.go | 4 +- 3 files changed, 46 insertions(+), 33 deletions(-) diff --git a/src/cmd/compile/internal/ssa/loopbce.go b/src/cmd/compile/internal/ssa/loopbce.go index 0ad274fc074..403aed6b202 100644 --- a/src/cmd/compile/internal/ssa/loopbce.go +++ b/src/cmd/compile/internal/ssa/loopbce.go @@ -1,5 +1,7 @@ package ssa +import "fmt" + type indVar struct { ind *Value // induction variable inc *Value // increment, a constant @@ -138,11 +140,22 @@ nextb: } if f.pass.debug >= 1 { - if min.Op == OpConst64 { - b.Func.Warnl(b.Pos, "Induction variable with minimum %d and increment %d", min.AuxInt, inc.AuxInt) - } else { - b.Func.Warnl(b.Pos, "Induction variable with non-const minimum and increment %d", inc.AuxInt) + mlim1, mlim2 := fmt.Sprint(min.AuxInt), fmt.Sprint(max.AuxInt) + if !min.isGenericIntConst() { + if f.pass.debug >= 2 { + mlim1 = fmt.Sprint(min) + } else { + mlim1 = "?" + } } + if !max.isGenericIntConst() { + if f.pass.debug >= 2 { + mlim2 = fmt.Sprint(max) + } else { + mlim2 = "?" + } + } + b.Func.Warnl(b.Pos, "Induction variable: limits [%v,%v), increment %d", mlim1, mlim2, inc.AuxInt) } iv = append(iv, indVar{ diff --git a/test/loopbce.go b/test/loopbce.go index c742df7e60c..95dd6ff58f6 100644 --- a/test/loopbce.go +++ b/test/loopbce.go @@ -5,7 +5,7 @@ package main func f0a(a []int) int { x := 0 - for i := range a { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := range a { // ERROR "Induction variable: limits \[0,\?\), increment 1$" x += a[i] // ERROR "Proved IsInBounds$" } return x @@ -13,7 +13,7 @@ func f0a(a []int) int { func f0b(a []int) int { x := 0 - for i := range a { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := range a { // ERROR "Induction variable: limits \[0,\?\), increment 1$" b := a[i:] // ERROR "Proved IsSliceInBounds$" x += b[0] } @@ -22,7 +22,7 @@ func f0b(a []int) int { func f0c(a []int) int { x := 0 - for i := range a { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := range a { // ERROR "Induction variable: limits \[0,\?\), increment 1$" b := a[:i+1] // ERROR "Proved IsSliceInBounds$" x += b[0] } @@ -31,7 +31,7 @@ func f0c(a []int) int { func f1(a []int) int { x := 0 - for _, i := range a { // ERROR "Induction variable with minimum 0 and increment 1" + for _, i := range a { // ERROR "Induction variable: limits \[0,\?\), increment 1$" x += i } return x @@ -39,7 +39,7 @@ func f1(a []int) int { func f2(a []int) int { x := 0 - for i := 1; i < len(a); i++ { // ERROR "Induction variable with minimum 1 and increment 1$" + for i := 1; i < len(a); i++ { // ERROR "Induction variable: limits \[1,\?\), increment 1$" x += a[i] // ERROR "Proved IsInBounds$" } return x @@ -47,7 +47,7 @@ func f2(a []int) int { func f4(a [10]int) int { x := 0 - for i := 0; i < len(a); i += 2 { // ERROR "Induction variable with minimum 0 and increment 2$" + for i := 0; i < len(a); i += 2 { // ERROR "Induction variable: limits \[0,10\), increment 2$" x += a[i] // ERROR "Proved IsInBounds$" } return x @@ -55,14 +55,14 @@ func f4(a [10]int) int { func f5(a [10]int) int { x := 0 - for i := -10; i < len(a); i += 2 { // ERROR "Induction variable with minimum -10 and increment 2$" + for i := -10; i < len(a); i += 2 { // ERROR "Induction variable: limits \[-10,10\), increment 2$" x += a[i] } return x } func f6(a []int) { - for i := range a { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := range a { // ERROR "Induction variable: limits \[0,\?\), increment 1$" b := a[0:i] // ERROR "Proved IsSliceInBounds$" f6(b) } @@ -70,7 +70,7 @@ func f6(a []int) { func g0a(a string) int { x := 0 - for i := 0; i < len(a); i++ { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := 0; i < len(a); i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1$" x += int(a[i]) // ERROR "Proved IsInBounds$" } return x @@ -78,7 +78,7 @@ func g0a(a string) int { func g0b(a string) int { x := 0 - for i := 0; len(a) > i; i++ { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := 0; len(a) > i; i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1$" x += int(a[i]) // ERROR "Proved IsInBounds$" } return x @@ -87,7 +87,7 @@ func g0b(a string) int { func g1() int { a := "evenlength" x := 0 - for i := 0; i < len(a); i += 2 { // ERROR "Induction variable with minimum 0 and increment 2$" + for i := 0; i < len(a); i += 2 { // ERROR "Induction variable: limits \[0,10\), increment 2$" x += int(a[i]) // ERROR "Proved IsInBounds$" } return x @@ -96,7 +96,7 @@ func g1() int { func g2() int { a := "evenlength" x := 0 - for i := 0; i < len(a); i += 2 { // ERROR "Induction variable with minimum 0 and increment 2$" + for i := 0; i < len(a); i += 2 { // ERROR "Induction variable: limits \[0,10\), increment 2$" j := i if a[i] == 'e' { // ERROR "Proved IsInBounds$" j = j + 1 @@ -108,39 +108,39 @@ func g2() int { func g3a() { a := "this string has length 25" - for i := 0; i < len(a); i += 5 { // ERROR "Induction variable with minimum 0 and increment 5$" + for i := 0; i < len(a); i += 5 { // ERROR "Induction variable: limits \[0,25\), increment 5$" useString(a[i:]) // ERROR "Proved IsSliceInBounds$" useString(a[:i+3]) } } func g3b(a string) { - for i := 0; i < len(a); i++ { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := 0; i < len(a); i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1$" useString(a[i+1:]) // ERROR "Proved IsSliceInBounds$" } } func g3c(a string) { - for i := 0; i < len(a); i++ { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := 0; i < len(a); i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1$" useString(a[:i+1]) // ERROR "Proved IsSliceInBounds$" } } func h1(a []byte) { c := a[:128] - for i := range c { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := range c { // ERROR "Induction variable: limits \[0,128\), increment 1$" c[i] = byte(i) // ERROR "Proved IsInBounds$" } } func h2(a []byte) { - for i := range a[:128] { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := range a[:128] { // ERROR "Induction variable: limits \[0,128\), increment 1$" a[i] = byte(i) } } func k0(a [100]int) [100]int { - for i := 10; i < 90; i++ { // ERROR "Induction variable with minimum 10 and increment 1$" + for i := 10; i < 90; i++ { // ERROR "Induction variable: limits \[10,90\), increment 1$" a[i-11] = i a[i-10] = i // ERROR "Proved IsInBounds$" a[i-5] = i // ERROR "Proved IsInBounds$" @@ -153,7 +153,7 @@ func k0(a [100]int) [100]int { } func k1(a [100]int) [100]int { - for i := 10; i < 90; i++ { // ERROR "Induction variable with minimum 10 and increment 1$" + for i := 10; i < 90; i++ { // ERROR "Induction variable: limits \[10,90\), increment 1$" useSlice(a[:i-11]) useSlice(a[:i-10]) // ERROR "Proved IsSliceInBounds$" useSlice(a[:i-5]) // ERROR "Proved IsSliceInBounds$" @@ -168,7 +168,7 @@ func k1(a [100]int) [100]int { } func k2(a [100]int) [100]int { - for i := 10; i < 90; i++ { // ERROR "Induction variable with minimum 10 and increment 1$" + for i := 10; i < 90; i++ { // ERROR "Induction variable: limits \[10,90\), increment 1$" useSlice(a[i-11:]) useSlice(a[i-10:]) // ERROR "Proved IsSliceInBounds$" useSlice(a[i-5:]) // ERROR "Proved IsSliceInBounds$" @@ -182,7 +182,7 @@ func k2(a [100]int) [100]int { } func k3(a [100]int) [100]int { - for i := -10; i < 90; i++ { // ERROR "Induction variable with minimum -10 and increment 1$" + for i := -10; i < 90; i++ { // ERROR "Induction variable: limits \[-10,90\), increment 1$" a[i+9] = i a[i+10] = i // ERROR "Proved IsInBounds$" a[i+11] = i @@ -192,7 +192,7 @@ func k3(a [100]int) [100]int { func k4(a [100]int) [100]int { min := (-1) << 63 - for i := min; i < min+50; i++ { // ERROR "Induction variable with minimum -9223372036854775808 and increment 1$" + for i := min; i < min+50; i++ { // ERROR "Induction variable: limits \[-9223372036854775808,-9223372036854775758\), increment 1$" a[i-min] = i // ERROR "Proved IsInBounds$" } return a @@ -200,7 +200,7 @@ func k4(a [100]int) [100]int { func k5(a [100]int) [100]int { max := (1 << 63) - 1 - for i := max - 50; i < max; i++ { // ERROR "Induction variable with minimum 9223372036854775757 and increment 1$" + for i := max - 50; i < max; i++ { // ERROR "Induction variable: limits \[9223372036854775757,9223372036854775807\), increment 1" a[i-max+50] = i // ERROR "Proved IsInBounds$" a[i-(max-70)] = i // ERROR "Proved IsInBounds$" } @@ -224,13 +224,13 @@ func nobce1() { } func nobce2(a string) { - for i := int64(0); i < int64(len(a)); i++ { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := int64(0); i < int64(len(a)); i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1$" useString(a[i:]) // ERROR "Proved IsSliceInBounds$" } - for i := int64(0); i < int64(len(a))-31337; i++ { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := int64(0); i < int64(len(a))-31337; i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1$" useString(a[i:]) // ERROR "Proved IsSliceInBounds$" } - for i := int64(0); i < int64(len(a))+int64(-1<<63); i++ { // ERROR "Induction variable with minimum 0 and increment 1$" + for i := int64(0); i < int64(len(a))+int64(-1<<63); i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1$" // tests an overflow of StringLen-MinInt64 useString(a[i:]) } @@ -239,7 +239,7 @@ func nobce2(a string) { func nobce3(a [100]int64) [100]int64 { min := int64((-1) << 63) max := int64((1 << 63) - 1) - for i := min; i < max; i++ { // ERROR "Induction variable with minimum -9223372036854775808 and increment 1$" + for i := min; i < max; i++ { // ERROR "Induction variable: limits \[-9223372036854775808,9223372036854775807\), increment 1$" a[i] = i } return a diff --git a/test/prove.go b/test/prove.go index a4eedbb717b..b5b3f20082f 100644 --- a/test/prove.go +++ b/test/prove.go @@ -62,7 +62,7 @@ func f1c(a []int, i int64) int { } func f2(a []int) int { - for i := range a { // ERROR "Induction variable with minimum 0 and increment 1" + for i := range a { // ERROR "Induction variable: limits \[0,\?\), increment 1" a[i+1] = i a[i+1] = i // ERROR "Proved IsInBounds$" } @@ -464,7 +464,7 @@ func f16(s []int) []int { } func f17(b []int) { - for i := 0; i < len(b); i++ { // ERROR "Induction variable with minimum 0 and increment 1" + for i := 0; i < len(b); i++ { // ERROR "Induction variable: limits \[0,\?\), increment 1" // This tests for i <= cap, which we can only prove // using the derived relation between len and cap. // This depends on finding the contradiction, since we