Index: test/msan/param_tls_limit.cc
===================================================================
--- test/msan/param_tls_limit.cc
+++ test/msan/param_tls_limit.cc
@@ -14,65 +14,36 @@
 
 // This test assumes that ParamTLS size is 800 bytes.
 
-// This test passes poisoned values through function argument list.
-// In case of overflow, argument is unpoisoned.
-#define OVERFLOW(x) assert(__msan_test_shadow(&x, sizeof(x)) == -1)
-// In case of no overflow, it is still poisoned.
-#define NO_OVERFLOW(x) assert(__msan_test_shadow(&x, sizeof(x)) == 0)
+// This test passes partly poisoned values through function argument list.
+
+// argument is initialized
+#define NO_POISON(x) assert(__msan_test_shadow(&x, sizeof(x)) == -1)
+
+// some part of argument is uninitialized
+#define POISON(x) assert(__msan_test_shadow(&x, sizeof(x)) != -1)
+
+#define PARTIALLY_INIT(s) for(int i=0; i < sizeof(s)-1 ; i++) {s.x[i] = 'i';}
 
 template<int N>
 struct S {
   char x[N];
 };
 
-void f100(S<100> s) {
-  NO_OVERFLOW(s);
-}
-
 void f800(S<800> s) {
-  NO_OVERFLOW(s);
+  POISON(s);
 }
 
 void f801(S<801> s) {
-  OVERFLOW(s);
-}
-
-void f1000(S<1000> s) {
-  OVERFLOW(s);
-}
-
-void f_many(int a, double b, S<800> s, int c, double d) {
-  NO_OVERFLOW(a);
-  NO_OVERFLOW(b);
-  OVERFLOW(s);
-  OVERFLOW(c);
-  OVERFLOW(d);
-}
-
-// -8 bytes for "int a", aligned by 8
-// -2 to make "int c" a partial fit
-void f_many2(int a, S<800 - 8 - 2> s, int c, double d) {
-  NO_OVERFLOW(a);
-  NO_OVERFLOW(s);
-  OVERFLOW(c);
-  OVERFLOW(d);
+  // poision only till the size of ParamTLS will get detected
+  NO_POISON(s);
 }
 
 int main(void) {
-  S<100> s100;
   S<800> s800;
   S<801> s801;
-  S<1000> s1000;
-  f100(s100);
+  PARTIALLY_INIT(s800);
+  PARTIALLY_INIT(s801);
   f800(s800);
   f801(s801);
-  f1000(s1000);
-
-  int i;
-  double d;
-  f_many(i, d, s800, i, d);
-
-  S<800 - 8 - 2> s788;
-  f_many2(i, s788, i, d);
   return 0;
 }