[libFuzzer] Increase the iteration limit in shrink.test

After https://reviews.llvm.org/D48800, shrink.test started failing on
x86_64h architecture.
Looking into this, the optimization pass is too eager to unroll the loop
on x86_64h, possibly leading to worse coverage data.

Alternative solutions include not unrolling the loop when fuzzing, or
disabling this test on that architecture.

Differential Revision: https://reviews.llvm.org/D50484

llvm-svn: 339303

compiler-rt/test/fuzzer/shrink.test

@@ -1,6 +1,6 @@
 RUN: %cpp_compiler %S/ShrinkControlFlowTest.cpp -o %t-ShrinkControlFlowTest
 RUN: %cpp_compiler %S/ShrinkValueProfileTest.cpp -o %t-ShrinkValueProfileTest
-RUN: %run %t-ShrinkControlFlowTest -seed=1 -exit_on_item=0eb8e4ed029b774d80f2b66408203801cb982a60 -runs=1000000  -shrink=1 -reduce_inputs=0 2>&1 | FileCheck %s --check-prefix=SHRINK1
+RUN: %run %t-ShrinkControlFlowTest -seed=1 -exit_on_item=0eb8e4ed029b774d80f2b66408203801cb982a60 -runs=2000000  -shrink=1 -reduce_inputs=0 2>&1 | FileCheck %s --check-prefix=SHRINK1
 # Limit max_len to run this negative test faster.
 RUN: %run %t-ShrinkControlFlowTest -seed=1 -exit_on_item=0eb8e4ed029b774d80f2b66408203801cb982a60 -runs=1000000 -shrink=0 -reduce_inputs=0 -max_len=64 2>&1 | FileCheck %s --check-prefix=SHRINK0
 RUN: %run %t-ShrinkValueProfileTest -seed=1 -exit_on_item=aea2e3923af219a8956f626558ef32f30a914ebc -runs=100000 -shrink=1 -reduce_inputs=0 -use_value_profile=1 2>&1 | FileCheck %s --check-prefix=SHRINK1_VP