[llvm] r230941 - Teach the verifier to enforce that the alignment argument of memory intrinsics must be a power of 2.

[Owen Anderson]

Author: resistor
Date: Mon Mar  2 03:35:06 2015
New Revision: 230941

URL: http://llvm.org/viewvc/llvm-project?rev=230941&view=rev
Log:
Teach the verifier to enforce that the alignment argument of memory intrinsics must be a power of 2.

Added:
    llvm/trunk/test/Verifier/memcpy.ll
Modified:
    llvm/trunk/lib/IR/Verifier.cpp

Modified: llvm/trunk/lib/IR/Verifier.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/Verifier.cpp?rev=230941&r1=230940&r2=230941&view=diff
==============================================================================
--- llvm/trunk/lib/IR/Verifier.cpp (original)
+++ llvm/trunk/lib/IR/Verifier.cpp Mon Mar  2 03:35:06 2015
@@ -2796,14 +2796,20 @@ void Verifier::visitIntrinsicFunctionCal
   } break;
   case Intrinsic::memcpy:
   case Intrinsic::memmove:
-  case Intrinsic::memset:
-    Assert1(isa<ConstantInt>(CI.getArgOperand(3)),
+  case Intrinsic::memset: {
+    ConstantInt *AlignCI = dyn_cast<ConstantInt>(CI.getArgOperand(3));
+    Assert1(AlignCI,
             "alignment argument of memory intrinsics must be a constant int",
             &CI);
+    const APInt &AlignVal = AlignCI->getValue();
+    Assert1(AlignCI->isZero() || AlignVal.isPowerOf2(),
+            "alignment argument of memory intrinsics must be a power of 2",
+            &CI);
     Assert1(isa<ConstantInt>(CI.getArgOperand(4)),
             "isvolatile argument of memory intrinsics must be a constant int",
             &CI);
     break;
+  }
   case Intrinsic::gcroot:
   case Intrinsic::gcwrite:
   case Intrinsic::gcread:

Added: llvm/trunk/test/Verifier/memcpy.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Verifier/memcpy.ll?rev=230941&view=auto
==============================================================================
--- llvm/trunk/test/Verifier/memcpy.ll (added)
+++ llvm/trunk/test/Verifier/memcpy.ll Mon Mar  2 03:35:06 2015
@@ -0,0 +1,9 @@
+; RUN: not opt -verify < %s 2>&1 | FileCheck %s
+
+; CHECK: alignment argument of memory intrinsics must be a power of 2 
+
+define void @foo(i8* %P, i8* %Q) {
+  call void @llvm.memcpy.p0i8.p0i8.i32(i8* %P, i8* %Q, i32 4, i32 3, i1 false)
+  ret void
+}
+declare void @llvm.memcpy.p0i8.p0i8.i32(i8* nocapture, i8* nocapture, i32, i32, i1) nounwind