From 76e32dfbc0acecb33e2141a0c2faf5b23e1342fc Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault@amd.com>
Date: Wed, 18 May 2016 16:10:24 +0000
Subject: [PATCH] AMDGPU: Error if branch distance exceeds limit

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269951 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/AMDGPU/MCTargetDesc/AMDGPUAsmBackend.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/lib/Target/AMDGPU/MCTargetDesc/AMDGPUAsmBackend.cpp b/lib/Target/AMDGPU/MCTargetDesc/AMDGPUAsmBackend.cpp
index c7c4cf0969d..933c167f013 100644
--- a/lib/Target/AMDGPU/MCTargetDesc/AMDGPUAsmBackend.cpp
+++ b/lib/Target/AMDGPU/MCTargetDesc/AMDGPUAsmBackend.cpp
@@ -96,8 +96,12 @@ void AMDGPUAsmBackend::applyFixup(const MCFixup &Fixup, char *Data,
 
   switch ((unsigned)Fixup.getKind()) {
     case AMDGPU::fixup_si_sopp_br: {
+      int64_t BrImm = (Value - 4) / 4;
+      if (!isInt<16>(BrImm))
+        report_fatal_error("branch size exceeds simm16");
+
       uint16_t *Dst = (uint16_t*)(Data + Fixup.getOffset());
-      *Dst = (Value - 4) / 4;
+      *Dst = BrImm;
       break;
     }