[llvm] r222918 - [msan] Fix origin propagation for select of floats.

[Evgeniy Stepanov]

Author: eugenis
Date: Fri Nov 28 05:17:58 2014
New Revision: 222918

URL: http://llvm.org/viewvc/llvm-project?rev=222918&view=rev
Log:
[msan] Fix origin propagation for select of floats.

MSan does not assign origin for instrumentation temps (i.e. the ones that do
not come from the application code), but "select" instrumentation erroneously
tried to use one of those.

https://code.google.com/p/memory-sanitizer/issues/detail?id=78

Modified:
    llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
    llvm/trunk/test/Instrumentation/MemorySanitizer/missing_origin.ll

Modified: llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp?rev=222918&r1=222917&r2=222918&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp (original)
+++ llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp Fri Nov 28 05:17:58 2014
@@ -2452,9 +2452,10 @@ struct MemorySanitizerVisitor : public I
       }
       // a = select b, c, d
       // Oa = Sb ? Ob : (b ? Oc : Od)
-      setOrigin(&I, IRB.CreateSelect(
-                        Sb, getOrigin(I.getCondition()),
-                        IRB.CreateSelect(B, getOrigin(C), getOrigin(D))));
+      setOrigin(
+          &I, IRB.CreateSelect(Sb, getOrigin(I.getCondition()),
+                               IRB.CreateSelect(B, getOrigin(I.getTrueValue()),
+                                                getOrigin(I.getFalseValue()))));
     }
   }
 

Modified: llvm/trunk/test/Instrumentation/MemorySanitizer/missing_origin.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Instrumentation/MemorySanitizer/missing_origin.ll?rev=222918&r1=222917&r2=222918&view=diff
==============================================================================
--- llvm/trunk/test/Instrumentation/MemorySanitizer/missing_origin.ll (original)
+++ llvm/trunk/test/Instrumentation/MemorySanitizer/missing_origin.ll Fri Nov 28 05:17:58 2014
@@ -17,3 +17,17 @@ entry:
 ; CHECK: [[A:%.*]] = load i32* {{.*}}@__msan_param_origin_tls,
 ; CHECK: store i32 [[A]], i32* @__msan_retval_origin_tls
 ; CHECK: ret <4 x i32>
+
+
+; Regression test for origin propagation in "select i1, float, float".
+; https://code.google.com/p/memory-sanitizer/issues/detail?id=78
+
+define float @SelectFloat(i1 %b, float %x, float %y) nounwind uwtable sanitize_memory {
+entry:
+  %z = select i1 %b, float %x, float %y
+  ret float %z
+}
+
+; CHECK-LABEL: @SelectFloat(
+; CHECK-NOT: select {{.*}} i32 0, i32 0
+; CHECK: ret float