archive/jdk
1
0
Fork 0
mirror of https://github.com/openjdk/jdk.git synced 2025-08-25 13:54:38 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

8130832: Extend the WhiteBox API to provide information about the availability of compiler intrinsics

Browse source 
Add a new method, sun.hotspot.WhiteBox.isIntrinsicAvailable, that can be used to determine if an intrinsic is available.

Reviewed-by: kvn, jrose
This commit is contained in:
Zoltan Majo 2015-07-28 19:20:42 +02:00
parent f3d31d3866
commit 422cd18f23
14 changed files with 1347 additions and 607 deletions
Download patch file Download diff file Expand all files Collapse all files

52
hotspot/src/share/vm/compiler/abstractCompiler.hpp
View file

@ -66,6 +66,58 @@ class AbstractCompiler : public CHeapObj<mtCompiler> {
virtual bool supports_osr () { return true; }
virtual bool can_compile_method(methodHandle method) { return true; }
// Determine if the current compiler provides an intrinsic
// for method 'method'. An intrinsic is available if:
// - the intrinsic is enabled (by using the appropriate command-line flag) and
// - the platform on which the VM is running supports the intrinsic
// (i.e., the platform provides the instructions necessary for the compiler
// to generate the intrinsic code).
//
// The second parameter, 'compilation_context', is needed to implement functionality
// related to the DisableIntrinsic command-line flag. The DisableIntrinsic flag can
// be used to prohibit the C2 compiler (but not the C1 compiler) to use an intrinsic.
// There are three ways to disable an intrinsic using the DisableIntrinsic flag:
//
// (1) -XX:DisableIntrinsic=_hashCode,_getClass
// Disables intrinsification of _hashCode and _getClass globally
// (i.e., the intrinsified version the methods will not be used at all).
// (2) -XX:CompileCommand=option,aClass::aMethod,ccstr,DisableIntrinsic,_hashCode
// Disables intrinsification of _hashCode if it is called from
// aClass::aMethod (but not for any other call site of _hashCode)
// (3) -XX:CompileCommand=option,java.lang.ref.Reference::get,ccstr,DisableIntrinsic,_Reference_get
// Some methods are not compiled by C2. Instead, the C2 compiler
// returns directly the intrinsified version of these methods.
// The command above forces C2 to compile _Reference_get, but
// allows using the intrinsified version of _Reference_get at all
// other call sites.
//
// From the modes above, (1) disable intrinsics globally, (2) and (3)
// disable intrinsics on a per-method basis. In cases (2) and (3) the
// compilation context is aClass::aMethod and java.lang.ref.Reference::get,
// respectively.
virtual bool is_intrinsic_available(methodHandle method, methodHandle compilation_context) {
return false;
}
// Determines if an intrinsic is supported by the compiler, that is,
// the compiler provides the instructions necessary to generate
// the intrinsic code for method 'method'.
//
// The 'is_intrinsic_supported' method is a white list, that is,
// by default no intrinsics are supported by a compiler except
// the ones listed in the method. Overriding methods should conform
// to this behavior.
virtual bool is_intrinsic_supported(methodHandle method) {
return false;
}
// Implements compiler-specific processing of command-line flags.
// Processing of command-line flags common to all compilers is implemented
// in vmIntrinsicss::is_disabled_by_flag.
virtual bool is_intrinsic_disabled_by_flag(methodHandle method) {
return false;
}
// Compiler type queries.
bool is_c1() { return _type == c1; }
bool is_c2() { return _type == c2; }