From 1fa3c728b9812cd38cd97a5ecfa2ef05feee7f6c Mon Sep 17 00:00:00 2001
From: Rui Ueyama <ruiu@google.com>
Date: Fri, 25 May 2018 21:14:45 +0000
Subject: [PATCH] Fix retpoline PLT for x86-64 when used for >4GB address.

Previously, we wrote only the least significant 32 bits.

llvm-svn: 333313
---
 lld/ELF/Arch/X86_64.cpp             |  2 +-
 lld/test/ELF/x86-64-plt-high-addr.s | 12 ++++++++++--
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/lld/ELF/Arch/X86_64.cpp b/lld/ELF/Arch/X86_64.cpp
index 605e2c19982f..8fd28d3bb278 100644
--- a/lld/ELF/Arch/X86_64.cpp
+++ b/lld/ELF/Arch/X86_64.cpp
@@ -497,7 +497,7 @@ template <class ELFT> Retpoline<ELFT>::Retpoline() {
 
 template <class ELFT>
 void Retpoline<ELFT>::writeGotPlt(uint8_t *Buf, const Symbol &S) const {
-  write32le(Buf, S.getPltVA() + 17);
+  write64le(Buf, S.getPltVA() + 17);
 }
 
 template <class ELFT> void Retpoline<ELFT>::writePltHeader(uint8_t *Buf) const {
diff --git a/lld/test/ELF/x86-64-plt-high-addr.s b/lld/test/ELF/x86-64-plt-high-addr.s
index 0626abd31aec..4acccb63f4a7 100644
--- a/lld/test/ELF/x86-64-plt-high-addr.s
+++ b/lld/test/ELF/x86-64-plt-high-addr.s
@@ -4,13 +4,21 @@
 // RUN: ld.lld -o %t.so -shared %t1.o
 
 // RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t2.o
-// RUN: ld.lld -o %t.exe %t2.o %t.so -image-base=0xcafe00000000
-// RUN: llvm-objdump -s -j .got.plt %t.exe | FileCheck %s
+// RUN: ld.lld -o %t1.exe %t2.o %t.so -image-base=0xcafe00000000
+// RUN: llvm-objdump -s -j .got.plt %t1.exe | FileCheck %s
 
 // CHECK:      Contents of section .got.plt:
 // CHECK-NEXT: cafe00002000 00300000 feca0000 00000000 00000000
 // CHECK-NEXT: cafe00002010 00000000 00000000 26100000 feca0000
 
+// RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t2.o
+// RUN: ld.lld -o %t2.exe %t2.o %t.so -image-base=0xcafe00000000 -z retpolineplt
+// RUN: llvm-objdump -s -j .got.plt %t2.exe | FileCheck -check-prefix=RETPOLINE %s
+
+// RETPOLINE:      Contents of section .got.plt:
+// RETPOLINE-NEXT: cafe00002000 00300000 feca0000 00000000 00000000
+// RETPOLINE-NEXT: cafe00002010 00000000 00000000 51100000 feca0000
+
 .global _start
 _start:
   jmp bar@PLT