RFR: 8243205: Modularize JVM flags declaration

[Ioi Lam]

On Thu, 3 Dec 2020 23:15:17 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

> What is the include architecture of this? compiler_globals.hpp includes c1_globals.hpp includes c1_globals_pd.hpp ?

c1_globals.hpp declares the flags, and c1_globals_pd.hpp defines the (platform-specific) default values of the flags. 

For example, c1_globals.hpp includes c1_globals_x86.hpp, which has
define_pd_global(bool,   CICompileOSR,                 true );
which gets preprocessed to:
const bool pd_CICompileOSR = true;;

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PR: https://git.openjdk.java.net/jdk/pull/1608