[msan] Fix handling of array types.

Switch array type shadow from a single integer to
an array of integers (i.e. make it per-element).
This simplifies instrumentation of extractvalue and fixes PR20493.

llvm-svn: 214398

diff --git a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
index 57e308c..3df1d15 100644 (file)
--- a/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp
@@ -763,6 +763,10 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
       return VectorType::get(IntegerType::get(*MS.C, EltSize),
                              VT->getNumElements());
     }
+    if (ArrayType *AT = dyn_cast<ArrayType>(OrigTy)) {
+      return ArrayType::get(getShadowTy(AT->getElementType()),
+                            AT->getNumElements());
+    }
     if (StructType *ST = dyn_cast<StructType>(OrigTy)) {
       SmallVector<Type*, 4> Elements;
       for (unsigned i = 0, n = ST->getNumElements(); i < n; i++)
@@ -882,11 +886,18 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> {
     assert(ShadowTy);
     if (isa<IntegerType>(ShadowTy) || isa<VectorType>(ShadowTy))
       return Constant::getAllOnesValue(ShadowTy);
-    StructType *ST = cast<StructType>(ShadowTy);
-    SmallVector<Constant *, 4> Vals;
-    for (unsigned i = 0, n = ST->getNumElements(); i < n; i++)
-      Vals.push_back(getPoisonedShadow(ST->getElementType(i)));
-    return ConstantStruct::get(ST, Vals);
+    if (ArrayType *AT = dyn_cast<ArrayType>(ShadowTy)) {
+      SmallVector<Constant *, 4> Vals(AT->getNumElements(),
+                                      getPoisonedShadow(AT->getElementType()));
+      return ConstantArray::get(AT, Vals);
+    }
+    if (StructType *ST = dyn_cast<StructType>(ShadowTy)) {
+      SmallVector<Constant *, 4> Vals;
+      for (unsigned i = 0, n = ST->getNumElements(); i < n; i++)
+        Vals.push_back(getPoisonedShadow(ST->getElementType(i)));
+      return ConstantStruct::get(ST, Vals);
+    }
+    llvm_unreachable("Unexpected shadow type");
   }
 
   /// \brief Create a dirty shadow for a given value.

diff --git a/llvm/test/Instrumentation/MemorySanitizer/array_types.ll b/llvm/test/Instrumentation/MemorySanitizer/array_types.ll
new file mode 100644 (file)
index 0000000..fa3835f
--- /dev/null
+++ b/llvm/test/Instrumentation/MemorySanitizer/array_types.ll
@@ -0,0 +1,89 @@
+; RUN: opt < %s -msan -msan-check-access-address=0 -S | FileCheck %s
+; RUN: opt < %s -msan -msan-check-access-address=0 -msan-track-origins=1 -S | FileCheck -check-prefix=CHECK -check-prefix=CHECK-ORIGINS %s
+
+target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define [2 x i32] @InsertValue(i32 %x, i32 %y) sanitize_memory {
+entry:
+  %a = insertvalue [2 x i32] undef, i32 %x, 0
+  %b = insertvalue [2 x i32] %a, i32 %y, 1
+  ret [2 x i32] %b
+}
+
+; CHECK-LABEL: @InsertValue(
+; CHECK-DAG: [[Sy:%.*]] = load i32* {{.*}}@__msan_param_tls to i64), i64 8) to i32*)
+; CHECK-DAG: [[Sx:%.*]] = load i32* {{.*}}@__msan_param_tls to i32*)
+; CHECK: [[A:%.*]] = insertvalue [2 x i32] [i32 -1, i32 -1], i32 [[Sx]], 0
+; CHECK: [[B:%.*]] = insertvalue [2 x i32] [[A]], i32 [[Sy]], 1
+; CHECK: store [2 x i32] [[B]], [2 x i32]* {{.*}}@__msan_retval_tls
+; CHECK: ret [2 x i32]
+
+
+define [2 x double] @InsertValueDouble(double %x, double %y) sanitize_memory {
+entry:
+  %a = insertvalue [2 x double] undef, double %x, 0
+  %b = insertvalue [2 x double] %a, double %y, 1
+  ret [2 x double] %b
+}
+
+; CHECK-LABEL: @InsertValueDouble(
+; CHECK-DAG: [[Sy:%.*]] = load i64* {{.*}}@__msan_param_tls to i64), i64 8) to i64*)
+; CHECK-DAG: [[Sx:%.*]] = load i64* getelementptr {{.*}}@__msan_param_tls, i32 0, i32 0
+; CHECK: [[A:%.*]] = insertvalue [2 x i64] [i64 -1, i64 -1], i64 [[Sx]], 0
+; CHECK: [[B:%.*]] = insertvalue [2 x i64] [[A]], i64 [[Sy]], 1
+; CHECK: store [2 x i64] [[B]], [2 x i64]* {{.*}}@__msan_retval_tls
+; CHECK: ret [2 x double]
+
+
+define i32 @ExtractValue([2 x i32] %a) sanitize_memory {
+entry:
+  %x = extractvalue [2 x i32] %a, 1
+  ret i32 %x
+}
+
+; CHECK-LABEL: @ExtractValue(
+; CHECK: [[Sa:%.*]] = load [2 x i32]* {{.*}}@__msan_param_tls to [2 x i32]*)
+; CHECK: [[Sx:%.*]] = extractvalue [2 x i32] [[Sa]], 1
+; CHECK: store i32 [[Sx]], i32* {{.*}}@__msan_retval_tls
+; CHECK: ret i32
+
+
+; Regression test for PR20493.
+
+%MyStruct = type { i32, i32, [3 x i32] }
+
+define i32 @ArrayInStruct(%MyStruct %s) sanitize_memory {
+  %x = extractvalue %MyStruct %s, 2, 1
+  ret i32 %x
+}
+
+; CHECK-LABEL: @ArrayInStruct(
+; CHECK: [[Ss:%.*]] = load { i32, i32, [3 x i32] }* {{.*}}@__msan_param_tls to { i32, i32, [3 x i32] }*)
+; CHECK: [[Sx:%.*]] = extractvalue { i32, i32, [3 x i32] } [[Ss]], 2, 1
+; CHECK: store i32 [[Sx]], i32* {{.*}}@__msan_retval_tls
+; CHECK: ret i32
+
+
+define i32 @ArrayOfStructs([3 x { i32, i32 }] %a) sanitize_memory {
+  %x = extractvalue [3 x { i32, i32 }] %a, 2, 1
+  ret i32 %x
+}
+
+; CHECK-LABEL: @ArrayOfStructs(
+; CHECK: [[Ss:%.*]] = load [3 x { i32, i32 }]* {{.*}}@__msan_param_tls to [3 x { i32, i32 }]*)
+; CHECK: [[Sx:%.*]] = extractvalue [3 x { i32, i32 }] [[Ss]], 2, 1
+; CHECK: store i32 [[Sx]], i32* {{.*}}@__msan_retval_tls
+; CHECK: ret i32
+
+
+define <8 x i16> @ArrayOfVectors([3 x <8 x i16>] %a) sanitize_memory {
+  %x = extractvalue [3 x <8 x i16>] %a, 1
+  ret <8 x i16> %x
+}
+
+; CHECK-LABEL: @ArrayOfVectors(
+; CHECK: [[Ss:%.*]] = load [3 x <8 x i16>]* {{.*}}@__msan_param_tls to [3 x <8 x i16>]*)
+; CHECK: [[Sx:%.*]] = extractvalue [3 x <8 x i16>] [[Ss]], 1
+; CHECK: store <8 x i16> [[Sx]], <8 x i16>* {{.*}}@__msan_retval_tls
+; CHECK: ret <8 x i16>