8057737: Avoid G1 write barriers on newly allocated objects Reviewed-by: mgerdin, kvn, iveresov Contributed-by: Staffan Friberg <staffan.friberg@oracle.com>

8059758: Footprint regressions with JDK-8038423 Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything. Reviewed-by: jwilhelm, brutisso

8059604: Add CompileThresholdScaling flag to control when methods are first compiled (with and withour TieredCompilation) Summary: This patch adds a new flag (CompileThresholdScaling) to control when methods are first compiled Reviewed-by: anoll, iveresov, kvn

8060215: per-method PrintIdealGraphLevel Summary: Use CompileCommand=option to set PrintIdealGraphLevel on a per-method level. Introduce the PrintIdealGraph develop to control/check if printing the graph is enabled for any method Reviewed-by: kvn, dlong, thartmann

8046268: compiler/whitebox/ tests fail : must be osr_compiled Summary: Added code to 'warm up' the methods before triggering OSR compilation by executing them a limited number of times. Like this, the profile information marks the loop exit as taken and we don't add an uncommon trap. Reviewed-by: kvn, dlong, iignatyev

Merge