Initialize ir->branch_table->PC with safe value #462
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jserv
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Benchmarks
| Benchmark suite | Current: b65d24c | Previous: 1e4ef3c | Ratio |
|---|---|---|---|
Dhrystone |
5 Average DMIPS over 10 runs |
5 Average DMIPS over 10 runs |
1 |
Coremark |
0.004 Average iterations/sec over 10 runs |
0.004 Average iterations/sec over 10 runs |
1 |
This comment was automatically generated by workflow using github-action-benchmark.
If the ra(return address) is 0x0, the LOOKUP_OR_UPDATE_BRANCH_HISTORY_TABLE will bahave abnormally since calloc initializes ir->branch_table->PC[i] to 0x0. The address 0x0 might be not yet translated to a valid block, thus ir->branch_table->target[i] might be NULL, accessing a NULL pointer causes segmentation fault. It can be solved by initializing ir->branch_table->PC with other value than 0x0. Here, I choose unsigned integer of -1. Close sysprog21#461
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…init Initialize ir->branch_table->PC with safe value
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If the ra(return address) is 0x0, the
LOOKUP_OR_UPDATE_BRANCH_HISTORY_TABLE will bahave abnormally since calloc initialize ir->branch_table->PC[i] to 0x0. The 0x0 address might be not yet translated to a valid block, thus ir->branch_table->target[i] might be NULL, calling a NULL function pointer cause segmentation fault. It can be solved by initializing ir->branch_table->PC will other value than 0x0. Here, I choose unsigned integer of -1.
Close #461