From 2defbada38d1a8fe8c215aa162b26e4db19e69b3 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Tue, 9 Dec 2014 19:10:03 +0000
Subject: [PATCH] AsmParser: Don't crash on short hex constants for fp128 types

If we see 0xL01, treat it like 0xL00000000000000000000000000000001
instead of crashing.

llvm-svn: 223811
---
 llvm/lib/AsmParser/LLLexer.cpp       | 12 +++++++-----
 llvm/test/Assembler/short-hexpair.ll |  4 ++++
 2 files changed, 11 insertions(+), 5 deletions(-)
 create mode 100644 llvm/test/Assembler/short-hexpair.ll

diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index 614a283241ec..d2ed616e7821 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -78,13 +78,15 @@ uint64_t LLLexer::HexIntToVal(const char *Buffer, const char *End) {
 void LLLexer::HexToIntPair(const char *Buffer, const char *End,
                            uint64_t Pair[2]) {
   Pair[0] = 0;
-  for (int i=0; i<16; i++, Buffer++) {
-    assert(Buffer != End);
-    Pair[0] *= 16;
-    Pair[0] += hexDigitValue(*Buffer);
+  if (End - Buffer >= 16) {
+    for (int i = 0; i < 16; i++, Buffer++) {
+      assert(Buffer != End);
+      Pair[0] *= 16;
+      Pair[0] += hexDigitValue(*Buffer);
+    }
   }
   Pair[1] = 0;
-  for (int i=0; i<16 && Buffer != End; i++, Buffer++) {
+  for (int i = 0; i < 16 && Buffer != End; i++, Buffer++) {
     Pair[1] *= 16;
     Pair[1] += hexDigitValue(*Buffer);
   }
diff --git a/llvm/test/Assembler/short-hexpair.ll b/llvm/test/Assembler/short-hexpair.ll
new file mode 100644
index 000000000000..067ea30b0ddb
--- /dev/null
+++ b/llvm/test/Assembler/short-hexpair.ll
@@ -0,0 +1,4 @@
+; RUN: llvm-as < %s | llvm-dis | FileCheck %s
+
+@x = global fp128 0xL01
+; CHECK: @x = global fp128 0xL00000000000000000000000000000001