diff --git a/src/cmd/internal/obj/ppc64/asm9.go b/src/cmd/internal/obj/ppc64/asm9.go
index b62eda8b14..90bee3d9b6 100644
--- a/src/cmd/internal/obj/ppc64/asm9.go
+++ b/src/cmd/internal/obj/ppc64/asm9.go
@@ -627,8 +627,6 @@ func addpad(pc, a int64, ctxt *obj.Link) int {
 		}
 	case 16:
 		switch pc % 16 {
-		// When currently aligned to 4, avoid 3 NOPs and set to
-		// 8 byte alignment which should still help.
 		case 4, 12:
 			return 4
 		case 8:
@@ -758,15 +756,20 @@ func span9(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 		if int(o.size) > 4*len(out) {
 			log.Fatalf("out array in span9 is too small, need at least %d for %v", o.size/4, p)
 		}
-		origsize := o.size
-		c.asmout(p, o, out[:])
-		if origsize == 0 && o.size > 0 {
-			for i = 0; i < int32(o.size/4); i++ {
-				c.ctxt.Arch.ByteOrder.PutUint32(bp, out[0])
-				bp = bp[4:]
+		// asmout is not set up to add large amounts of padding
+		if o.type_ == 0 && p.As == obj.APCALIGN {
+			pad := LOP_RRR(OP_OR, REGZERO, REGZERO, REGZERO)
+			aln := c.vregoff(&p.From)
+			v := addpad(p.Pc, aln, c.ctxt)
+			if v > 0 {
+				// Same padding instruction for all
+				for i = 0; i < int32(v/4); i++ {
+					c.ctxt.Arch.ByteOrder.PutUint32(bp, pad)
+					bp = bp[4:]
+				}
 			}
-			o.size = origsize
 		} else {
+			c.asmout(p, o, out[:])
 			for i = 0; i < int32(o.size/4); i++ {
 				c.ctxt.Arch.ByteOrder.PutUint32(bp, out[i])
 				bp = bp[4:]
@@ -2387,19 +2390,6 @@ func (c *ctxt9) asmout(p *obj.Prog, o *Optab, out []uint32) {
 		prasm(p)
 
 	case 0: /* pseudo ops */
-		if p.As == obj.APCALIGN {
-			aln := c.vregoff(&p.From)
-			v := addpad(p.Pc, aln, c.ctxt)
-			if v > 0 {
-				for i := 0; i < 6; i++ {
-					out[i] = uint32(0)
-				}
-				o.size = int8(v)
-				out[0] = LOP_RRR(OP_OR, REGZERO, REGZERO, REGZERO)
-				return
-			}
-			o.size = 0
-		}
 		break
 
 	case 1: /* mov r1,r2 ==> OR Rs,Rs,Ra */
diff --git a/src/cmd/internal/obj/ppc64/asm_test.go b/src/cmd/internal/obj/ppc64/asm_test.go
new file mode 100644
index 0000000000..fff478e552
--- /dev/null
+++ b/src/cmd/internal/obj/ppc64/asm_test.go
@@ -0,0 +1,81 @@
+// Copyright 2020 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 ppc64
+
+import (
+	"internal/testenv"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+var invalidPCAlignSrc = `
+TEXT test(SB),0,$0-0
+ADD $2, R3
+PCALIGN $32
+RET
+`
+var validPCAlignSrc = `
+TEXT test(SB),0,$0-0
+ADD $2, R3
+PCALIGN $16
+MOVD $8, R4
+ADD $8, R4
+PCALIGN $16
+ADD $8, R4
+PCALIGN $8
+ADD $4, R6
+PCALIGN $16
+ADD R2, R3, R4
+RET
+`
+
+// TestPCalign generates two asm files containing the
+// PCALIGN directive, to verify correct values are and
+// accepted, and incorrect values are flagged in error.
+func TestPCalign(t *testing.T) {
+	testenv.MustHaveGoBuild(t)
+
+	dir, err := ioutil.TempDir("", "testpcalign")
+	if err != nil {
+		t.Fatalf("could not create directory: %v", err)
+	}
+	defer os.RemoveAll(dir)
+
+	// generate a test with valid uses of PCALIGN
+
+	tmpfile := filepath.Join(dir, "x.s")
+	err = ioutil.WriteFile(tmpfile, []byte(validPCAlignSrc), 0644)
+	if err != nil {
+		t.Fatalf("can't write output: %v\n", err)
+	}
+
+	// build generated file without errors and assemble it
+	cmd := exec.Command(testenv.GoToolPath(t), "tool", "asm", "-o", filepath.Join(dir, "x.o"), "-S", tmpfile)
+	cmd.Env = append(os.Environ(), "GOARCH=ppc64le", "GOOS=linux")
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Errorf("Build failed: %v, output: %s", err, out)
+	}
+
+	// generate a test with invalid use of PCALIGN
+
+	tmpfile = filepath.Join(dir, "xi.s")
+	err = ioutil.WriteFile(tmpfile, []byte(invalidPCAlignSrc), 0644)
+	if err != nil {
+		t.Fatalf("can't write output: %v\n", err)
+	}
+
+	// build test with errors and check for messages
+	cmd = exec.Command(testenv.GoToolPath(t), "tool", "asm", "-o", filepath.Join(dir, "xi.o"), "-S", tmpfile)
+	cmd.Env = append(os.Environ(), "GOARCH=ppc64le", "GOOS=linux")
+	out, err = cmd.CombinedOutput()
+	if !strings.Contains(string(out), "Unexpected alignment") {
+		t.Errorf("Invalid alignment not detected for PCALIGN\n")
+	}
+}