Disallow the undocumented practice of starting the datalayout string with '-'.

Update some test cases accordingly.

llvm-svn: 168516

llvm/lib/VMCore/DataLayout.cpp

@@ -193,9 +193,6 @@ std::string DataLayout::parseSpecifier(StringRef Desc) {
     StringRef Token = Split.first;
     Desc = Split.second;
 
-    if (Token.empty())
-      continue;
-
     Split = Token.split(':');
     StringRef Specifier = Split.first;
     Token = Split.second;

llvm/test/Transforms/IndVarSimplify/iv-zext.ll

@@ -2,7 +2,7 @@
 ; CHECK-NOT: and
 ; CHECK-NOT: zext
 
-target datalayout = "-p:64:64:64-n32:64"
+target datalayout = "p:64:64:64-n32:64"
 
 define void @foo(double* %d, i64 %n) nounwind {
 entry:

llvm/test/Transforms/InstCombine/align-external.ll

@@ -8,7 +8,7 @@
 ; CHECK: %q = add i64 %r, 1
 ; CHECK: ret i64 %q
 
-target datalayout = "-i32:8:32"
+target datalayout = "i32:8:32"
 
 @A = external global i32
 @B = weak_odr global i32 0

llvm/test/Transforms/SimplifyLibCalls/Puts.ll

@@ -1,7 +1,7 @@
 ; Test that the PutsOptimizer works correctly
 ; RUN: opt < %s -simplify-libcalls -S | FileCheck %s
 
-target datalayout = "-p:64:64:64"
+target datalayout = "p:64:64:64"
 
 @.str = private constant [1 x i8] zeroinitializer