From: Andy Pan <panjf2000@gmail.com>
Date: Sun, 5 Apr 2020 14:21:11 +0000 (+0800)
Subject: cmd/internal/obj/ppc64: leverage AND operation to calculate remainder
X-Git-Tag: go1.15beta1~609
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=a3ef804891ab8185f604d4ae1a2fbb2449e61b2c;p=gostls13.git

cmd/internal/obj/ppc64: leverage AND operation to calculate remainder

Change-Id: I03e2a573eb778591071db4f783585a5d71a14c03
Reviewed-on: https://go-review.googlesource.com/c/go/+/227005
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
---

diff --git a/src/cmd/internal/obj/ppc64/asm9.go b/src/cmd/internal/obj/ppc64/asm9.go
index 90bee3d9b6..288e5f3360 100644
--- a/src/cmd/internal/obj/ppc64/asm9.go
+++ b/src/cmd/internal/obj/ppc64/asm9.go
@@ -54,7 +54,8 @@ type ctxt9 struct {
 // Instruction layout.
 
 const (
-	funcAlign = 16
+	funcAlign     = 16
+	funcAlignMask = funcAlign - 1
 )
 
 const (
@@ -622,11 +623,11 @@ var xcmp [C_NCLASS][C_NCLASS]bool
 func addpad(pc, a int64, ctxt *obj.Link) int {
 	switch a {
 	case 8:
-		if pc%8 != 0 {
+		if pc&7 != 0 {
 			return 4
 		}
 	case 16:
-		switch pc % 16 {
+		switch pc & 15 {
 		case 4, 12:
 			return 4
 		case 8:
@@ -735,8 +736,8 @@ func span9(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 		c.cursym.Size = pc
 	}
 
-	if pc%funcAlign != 0 {
-		pc += funcAlign - (pc % funcAlign)
+	if r := pc & funcAlignMask; r != 0 {
+		pc += funcAlign - r
 	}
 
 	c.cursym.Size = pc