> This patch fleshes out the `os::register_code_area()` function on > Windows/ARM64, largely mimicking the code for the Windows/x64 port with > some key ARM64-specific changes. Specifically (and similar to the > Windows/x64 port), this patch registers a single handler for the entire > dynamically generated code region, generating `.pdata` records (that > correspond to the `RUNTIME_FUNCTION` struct) and `.xdata` records (that > correspond to the `UNWIND_INFO` struct). Together, these records enable > Windows to correctly dispatch exceptions. > > However, there are several differences in the Windows/ARM64 > implementation compared to that for Windows/x64. First, `.pdata` > records on Windows/ARM64 store metadata information for functions that > are at most 1MB in size. Since the HotSpot code cache area could be > larger than 1MB, we create as many `.pdata` records as necessary to span > the entire code cache area. > > Each `.pdata` record points a `.xdata` record, which (also) stores the > size of the function (although not the address), so we make multiple > `.pdata` records point to a shared `.xdata` record. The slight caveat > here is that the code cache area may not be a perfect multiple of 1MB, > so we create _two_ `.xdata` records: (a) one record for all N-1 records > that store the metadata for the 1MB regions of the code cache and (b) a > second record for the trailing size left over after dividing the code > cache area size into 1MB chunks. > > Due to the variable number of `.pdata` and `.xdata` records, we allocate > them just after the unwind record so that all these records have the > same lifetime and so that they don't need to be managed separately. > > Finally, since the Windows/ARM64 port uses Vectored Exception Handling, > any recoverable exceptions should have already been handled, so the > exception handling function introduced in this patch reports the > exception to the console. > > --------- > - [x] I confirm that I make this contribution in accordance with the [OpenJDK > Interim AI Policy](https://openjdk.org/legal/ai).
Ashay Rane has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision: - Merge branch 'main' into JDK-8387032-code-cache-exceptions - Shorten exception message in test and add JBS issue ID - Compile libCodeCacheRuntimeFunctionTableTest.c only on Windows/ARM64 - Generate EH-only unwind info for code cache area on Windows/ARM64 This patch fleshes out the `os::register_code_area()` function on Windows/ARM64, largely mimicking the code for the Windows/x64 port with some key ARM64-specific changes. Specifically (and similar to the Windows/x64 port), this patch registers a single handler for the entire dynamically generated code region, generating `.pdata` records (that correspond to the `RUNTIME_FUNCTION` struct) and `.xdata` records (that correspond to the `UNWIND_INFO` struct). Together, these records enable Windows to correctly dispatch exceptions. However, there are several differences in the Windows/ARM64 implementation compared to that for Windows/x64. First, `.pdata` records on Windows/ARM64 store metadata information for functions that are at most 1MB in size. Since the HotSpot code cache area could be larger than 1MB, we create as many `.pdata` records as necessary to span the entire code cache area. Each `.pdata` record points a `.xdata` record, which (also) stores the size of the function (although not the address), so we make multiple `.pdata` records point to a shared `.xdata` record. The slight caveat here is that the code cache area may not be a perfect multiple of 1MB, so we create _two_ `.xdata` records: (a) one records for all N-1 records that store the metadata for the 1MB regions of the code cache and (b) a second record for the trailing size left over after dividing the code cache area size into 1MB chunks. Due to the variable number of `.pdata` and `.xdata` records, we allocate them just after the unwind record so that all these records have the same lifetime and so that they don't need to be managed separately. Finally, since the Windows/ARM64 port uses Vectored Exception Handling, any recoverable exceptions should have already been handled, so the exception handling function introduced in this patch reports the exception to the console. ------------- Changes: - all: https://git.openjdk.org/jdk/pull/31614/files - new: https://git.openjdk.org/jdk/pull/31614/files/6beedd42..dd3fc793 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=31614&range=03 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=31614&range=02-03 Stats: 29539 lines in 865 files changed: 21285 ins; 4238 del; 4016 mod Patch: https://git.openjdk.org/jdk/pull/31614.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/31614/head:pull/31614 PR: https://git.openjdk.org/jdk/pull/31614
