[dev.boringcrypto] cmd: use notsha256 instead of md5, sha1, sha256

When we add GOEXPERIMENT=boringcrypto, the bootstrap process
will not converge if the compiler itself depends on the boringcrypto
cgo-based implementations of sha1 and sha256.

Using notsha256 avoids boringcrypto and makes bootstrap converge.
Removing md5 is not strictly necessary but it seemed worthwhile to
be consistent.

For #51940.

Change-Id: Iba649507e0964d1a49a1d16e463dd23c4e348f14
Reviewed-on: https://go-review.googlesource.com/c/go/+/402595
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>

1 files changed, 5 insertions, 4 deletions

diff --git a/src/cmd/compile/internal/ssa/print.go b/src/cmd/compile/internal/ssa/print.go
index 96cd2c7c90..aea9ce9e33 100644
--- a/src/cmd/compile/internal/ssa/print.go
+++ b/src/cmd/compile/internal/ssa/print.go
@@ -6,10 +6,11 @@ package ssa
 
 import (
 	"bytes"
-	"cmd/internal/src"
-	"crypto/sha256"
 	"fmt"
 	"io"
+
+	"cmd/internal/notsha256"
+	"cmd/internal/src"
 )
 
 func printFunc(f *Func) {
@@ -17,7 +18,7 @@ func printFunc(f *Func) {
 }
 
 func hashFunc(f *Func) []byte {
-	h := sha256.New()
+	h := notsha256.New()
 	p := stringFuncPrinter{w: h, printDead: true}
 	fprintFunc(p, f)
 	return h.Sum(nil)
@@ -32,7 +33,7 @@ func (f *Func) String() string {
 
 // rewriteHash returns a hash of f suitable for detecting rewrite cycles.
 func (f *Func) rewriteHash() string {
-	h := sha256.New()
+	h := notsha256.New()
 	p := stringFuncPrinter{w: h, printDead: false}
 	fprintFunc(p, f)
 	return fmt.Sprintf("%x", h.Sum(nil))