Re: [Tarantool-patches] [PATCH luajit] ARM64: Fix exit stub patching.

[Igor Munkin via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

Found several typos after sending the patch. Fixed and force-pushed the
changes to the branch.

On 18.08.21, Igor Munkin wrote:
> From: Mike Pall <mike>
> 
> Contributed by Javier Guerra Giraldez.
> 
> (cherry picked from commit 9da06535092d6d9dec442641a26c64bce5574322)
> 
> When the side trace is assembled, it is linked to its parent trace. For
> this purpose, JIT runs through the parent trace mcode and updates jump
> instruction targeted to the corresponding exitno. Prior to this patch,
> these instructions were patched unconditionally, that leads to errors if
> the jump target address is out of the value ranges specified in ARM64
> references[1][2][3][4][5][6].
> 
> As a result of the patch <lj_asm_patchexit> considers value ranges of
> the jump targets and updates directly only those instructions fitting
> the particular jump range. Moreover, the corresponding jump in the pad
> leading to <lj_vm_exit_handler> is also patched, so those instructions,
> that are not updated before, targets to the linked side trace too.
> 
> Additionaly, there is some refactoring of jump targets assembling in

Typo fixed: s/Additionaly/Additionally/.

> scope of this patch.
> 
> Igor Munkin:
> * added the description and the test for the problem
> 
> [1]: https://developer.arm.com/documentation/dui0801/g/A64-General-Instructions/B
> [2]: https://developer.arm.com/documentation/dui0801/g/A64-General-Instructions/B-cond
> [3]: https://developer.arm.com/documentation/dui0801/g/A64-General-Instructions/CBZ
> [4]: https://developer.arm.com/documentation/dui0801/g/A64-General-Instructions/CBNZ
> [5]: https://developer.arm.com/documentation/dui0801/g/A64-General-Instructions/TBZ
> [6]: https://developer.arm.com/documentation/dui0801/g/A64-General-Instructions/TBNZ
> 
> Resoves tarantool/tarantool#6098

Typo fixed: s/Resoves/Resolves/.

> Part of tarantool/tarantool#5629
> 
> Signed-off-by: Igor Munkin <imun@tarantool.org>
> ---
> 
> Issue: https://github.com/tarantool/tarantool/issues/6098
> Branch: https://github.com/tarantool/luajit/tree/imun/gh-6098-fix-luajit-tests-suite-failures
> CI: https://github.com/tarantool/tarantool/commit/67f92d2
> Related PR in LuaJIT repo: https://github.com/LuaJIT/LuaJIT/pull/429
> 

<snipped>

> diff --git a/test/tarantool-tests/gh-6098-fix-side-exit-patching-on-arm64.test.lua b/test/tarantool-tests/gh-6098-fix-side-exit-patching-on-arm64.test.lua
> new file mode 100644
> index 00000000..05e8904c
> --- /dev/null
> +++ b/test/tarantool-tests/gh-6098-fix-side-exit-patching-on-arm64.test.lua
> @@ -0,0 +1,129 @@

<snipped>

> +for i = 1, FUNCS do
> +  -- XXX: FNEW is NYI, hence loop recording fails at this point.
> +  -- The recording is aborted on purpose: we are going to record
> +  -- <FUNCS> number of traces for functions in <recfuncs>.
> +  -- Otherwise, loop recording might lead to a very long trace
> +  -- error (via return to a lower frame), or a trace with lots of
> +  -- side traces. We need neither of this, but just bunch of
> +  -- traces filling the avaiable mcode area.

================================================================================

diff --git a/test/tarantool-tests/gh-6098-fix-side-exit-patching-on-arm64.test.lua b/test/tarantool-tests/gh-6098-fix-side-exit-patching-on-arm64.test.lua
index 05e8904c..4dcf3e22 100644
--- a/test/tarantool-tests/gh-6098-fix-side-exit-patching-on-arm64.test.lua
+++ b/test/tarantool-tests/gh-6098-fix-side-exit-patching-on-arm64.test.lua
@@ -82,7 +82,7 @@ for i = 1, FUNCS do
   -- Otherwise, loop recording might lead to a very long trace
   -- error (via return to a lower frame), or a trace with lots of
   -- side traces. We need neither of this, but just bunch of
-  -- traces filling the avaiable mcode area.
+  -- traces filling the available mcode area.
   local function tnew(p)
     return {
       a = p + 1, f = p + 6,  k = p + 11, p = p + 16, u = p + 21, z = p + 26,

================================================================================

> +  local function tnew(p)

<snipped>

> -- 
> 2.25.0
> 

-- 
Best regards,
IM