1 files changed, 0 insertions, 46 deletions
diff --git a/src/cmd/compile/internal/ssa/rewrite.go b/src/cmd/compile/internal/ssa/rewrite.go
index 03c38827cc..61d4234c65 100644
--- a/src/cmd/compile/internal/ssa/rewrite.go
+++ b/src/cmd/compile/internal/ssa/rewrite.go
@@ -254,52 +254,6 @@ func isSamePtr(p1, p2 *Value) bool {
 	return false
 }
 
-// DUFFZERO consists of repeated blocks of 4 MOVUPSs + ADD,
-// See runtime/mkduff.go.
-const (
-	dzBlocks    = 16 // number of MOV/ADD blocks
-	dzBlockLen  = 4  // number of clears per block
-	dzBlockSize = 19 // size of instructions in a single block
-	dzMovSize   = 4  // size of single MOV instruction w/ offset
-	dzAddSize   = 4  // size of single ADD instruction
-	dzClearStep = 16 // number of bytes cleared by each MOV instruction
-
-	dzTailLen  = 4 // number of final STOSQ instructions
-	dzTailSize = 2 // size of single STOSQ instruction
-
-	dzClearLen = dzClearStep * dzBlockLen // bytes cleared by one block
-	dzSize     = dzBlocks * dzBlockSize
-)
-
-func duffStart(size int64) int64 {
-	x, _ := duff(size)
-	return x
-}
-func duffAdj(size int64) int64 {
-	_, x := duff(size)
-	return x
-}
-
-// duff returns the offset (from duffzero, in bytes) and pointer adjust (in bytes)
-// required to use the duffzero mechanism for a block of the given size.
-func duff(size int64) (int64, int64) {
-	if size < 32 || size > 1024 || size%dzClearStep != 0 {
-		panic("bad duffzero size")
-	}
-	// TODO: arch-dependent
-	steps := size / dzClearStep
-	blocks := steps / dzBlockLen
-	steps %= dzBlockLen
-	off := dzBlockSize * (dzBlocks - blocks)
-	var adj int64
-	if steps != 0 {
-		off -= dzAddSize
-		off -= dzMovSize * steps
-		adj -= dzClearStep * (dzBlockLen - steps)
-	}
-	return off, adj
-}
-
 // mergePoint finds a block among a's blocks which dominates b and is itself
 // dominated by all of a's blocks. Returns nil if it can't find one.
 // Might return nil even if one does exist.