8010437: guarantee(this->is8bit(imm8)) failed: Short forward jump exceeds 8-bit offset
Summary: Fix shorten_branches() to accurately count an initial nop that may be inserted in a block that starts with a safepoint.
Reviewed-by: kvn
8011102: Clear AVX registers after return from JNI call
Summary: Execute vzeroupper instruction after JNI call and on exits in jit compiled code which use 256bit vectors.
Reviewed-by: roland