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| author | Christian Krinitsin <mail@krinitsin.com> | 2025-07-16 14:55:48 +0200 |
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| committer | Christian Krinitsin <mail@krinitsin.com> | 2025-07-16 14:55:48 +0200 |
| commit | 63d2e9d409831aa8582787234cae4741847504b7 (patch) | |
| tree | 595fae753d2eb293437226eaab2eed208463f132 /results/scraper/box64/1661 | |
| parent | 2843bb65aeaeb86eb89bf3d9690db61b9dc6306e (diff) | |
| download | qemu-analysis-63d2e9d409831aa8582787234cae4741847504b7.tar.gz qemu-analysis-63d2e9d409831aa8582787234cae4741847504b7.zip | |
add box64 bug reports box64
Diffstat (limited to 'results/scraper/box64/1661')
| -rw-r--r-- | results/scraper/box64/1661 | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/results/scraper/box64/1661 b/results/scraper/box64/1661 new file mode 100644 index 000000000..e771d881a --- /dev/null +++ b/results/scraper/box64/1661 @@ -0,0 +1,45 @@ +Unexpected Dynarec-Interpreter Difference on `cmp` Instruction +I tried to run python3.12 with box64 on rv64 platform (prior issue #1652 ) and used `BOX64_DYNAREC_TEST=1` to test the differences between dynarec and interpreter. I saw 4 differences about `cmp` instruction: + +```txt +Warning, difference between x64 Interpreter and Dynarec in 0x3f001ea3f3 (7e 17 83 fe 63 7f 12 89) +======================================= +DIFF: Dynarec | Interpreter +---------------------- +RIP: 0000003f001ea40c | 0000003f001ea3f5 +Warning, difference between x64 Interpreter and Dynarec in 0x3f001ea36f (0f 8f bb 00 00 00 39 c3) +======================================= +DIFF: Dynarec | Interpreter +---------------------- +RIP: 0000003f001ea430 | 0000003f001ea375 +Warning, difference between x64 Interpreter and Dynarec in 0x3f001ea3f3 (7e 17 83 fe 63 7f 12 89) +======================================= +DIFF: Dynarec | Interpreter +---------------------- +RIP: 0000003f001ea40c | 0000003f001ea3f5 +Warning, difference between x64 Interpreter and Dynarec in 0x3f001ea36f (0f 8f bb 00 00 00 39 c3) +======================================= +DIFF: Dynarec | Interpreter +---------------------- +RIP: 0000003f001ea430 | 0000003f001ea375 +``` + +The relative RIP `0x3f001ea3f3` & `0x3f001ea36f` is actually in `libpython3.12.so` and `objdump` told me: + +```txt + (( omitted )) + 1ea369: 8b 41 3c mov 0x3c(%rcx),%eax + 1ea36c: 83 f8 63 cmp $0x63,%eax + 1ea36f: 0f 8f bb 00 00 00 jg 1ea430 <PyDict_Clear@@Base+0x3d0> + 1ea375: 39 c3 cmp %eax,%ebx + (( omitted )) + 1ea3ed: 44 0f 4c e0 cmovl %eax,%r12d + 1ea3f1: 39 f0 cmp %esi,%eax + 1ea3f3: 7e 17 jle 1ea40c <PyDict_Clear@@Base+0x3ac> + 1ea3f5: 83 fe 63 cmp $0x63,%esi + (( omitted )) +``` + +I guess this might be because `cmp` did not set x64 FLAGS correctly, thus the following `jle` & `jg` did not jump to correct address. But why? I have investigated the code for about 1 day and till now can not find out the reason. + +I would appreciate it if anyone could help to solve this problem or give some hints about this. Thanks in advance. \ No newline at end of file |