On Wed, 22 Mar 2023 14:09:07 GMT, Per Minborg <pminb...@openjdk.org> wrote:
>> API changes for the FFM API (third preview) >> >> Specdiff: >> https://cr.openjdk.org/~pminborg/panama/21/v1/specdiff/overview-summary.html >> >> Javadoc: >> https://cr.openjdk.org/~pminborg/panama/21/v1/javadoc/java.base/module-summary.html > > Per Minborg has updated the pull request incrementally with one additional > commit since the last revision: > > Improve javadocs for Linker::captureStateLayout src/java.base/share/classes/jdk/internal/foreign/abi/SharedUtils.java line 297: > 295: MethodType mtype = mh.type(); > 296: int[] perms = new int[mtype.parameterCount()]; > 297: MethodType swappedType = > MethodType.methodType(mtype.returnType()); Instead of `MethodType::appendParameterTypes(…)` (which performs an expensive lookup of a new cached `MethodType` value per call), this method should instead use a `Class<?>[]` for the arguments, which avoids that overhead inside a loop: public static MethodHandle swapArguments(MethodHandle mh, int firstArg, int secondArg) { MethodType mtype = mh.type(); int[] perms = new int[mtype.parameterCount()]; Class<?>[] ptypes = new Class<?>[perms.length]; for (int i = 0 ; i < perms.length ; i++) { int dst = i; if (i == firstArg) dst = secondArg; else if (i == secondArg) dst = firstArg; perms[i] = dst; ptypes[i] = mtype.parameterType(dst); } // This should use `JavaLangInvokeAccess` to invoke the internal // `MethodType.methodType(Class<?> rtype, Class<?>[] ptypes, boolean trusted)` // method with a `trusted` value of `true`: MethodType swappedType = MethodType.methodType(mtype.returnType(), ptypes); return permuteArguments(mh, swappedType, perms); } src/java.base/share/classes/jdk/internal/foreign/abi/fallback/LibFallback.java line 61: > 59: static final MemorySegment VOID_TYPE = > MemorySegment.ofAddress(ffi_type_void()); > 60: static final short STRUCT_TAG = ffi_type_struct(); > 61: private static final long SIZEOF_CIF = sizeofCif(); Won’t calling `ffi_default_abi()` (and the other `ffi_*()` methods) throw `UnsatisfiedLinkError` if `SUPPORTED` is `false`? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/13079#discussion_r1147259998 PR Review Comment: https://git.openjdk.org/jdk/pull/13079#discussion_r1147267292
