[Flang2] Fix duplicate TBAA type systems across modules #1460
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1997alireza
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In Flang, functions within the same module are assigned unique TBAA type system IDs based on their order, but functions in different modules can unintentionally receive the same ID, leading to incorrect non-aliasing results. This commit resolves the issue by appending a hash of the module name to each function type system metadata, ensuring unique type systems across modules and preventing aliasing errors.
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| @@ -2643,7 +2644,7 @@ get_omnipotent_pointer(LL_Module *module) | |||
| const char *baseName = "Flang FAA"; | |||
| const char *const omniName = "unlimited ptr"; | |||
| const char *const unObjName = "unref ptr"; | |||
| snprintf(baseBuff, 32, "%s %x", baseName, funcId); | |||
| snprintf(baseBuff, 32, "%s %zx %x", baseName, std::hash<std::string>{}(current_module->module_name), funcId); | |||
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Can you format this line according to LLVM Coding Standards?
| @@ -43,6 +43,7 @@ | |||
| #include "symfun.h" | |||
| #include "ilidir.h" | |||
| #include "fdirect.h" | |||
| #include <string> | |||
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Based on this build error, this #include statement should be placed above line 18 (#include "machreg.h"). In fact, all standard headers should be included before custom headers, including stdlib.h, stdio.h, etc.
| @@ -0,0 +1,18 @@ | |||
| ! This test contians two files, tbaa_multimod_01_caller.f90 and tbaa_multimod_01_callee.f90 | |||
| ! RUN: %flang -Wl,-mllvm,-aa-trace -fuse-ld=lld -flto=full -O3 %s %S/tbaa_multimod_01_callee.f90 -o - 2>&1 1>- | FileCheck %s | |||
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These tests are failing in the CI jobs. I understand that -aa-trace only works when LLVM has assertions enabled, but I believe that the GitHub workflow for classic-flang-llvm-project already configures LLVM with -DLLVM_ENABLE_ASSERTIONS=ON:
@1997alireza Can you build classic-flang-llvm-project using the same commands as used by the CI jobs, and confirm whether you can reproduce the test failures in your environment?
Currently, functions within the same module are assigned unique TBAA type system IDs based on their order, but functions in different modules can unintentionally receive the same ID, leading to incorrect non-aliasing results. This patch resolves the issue by appending a hash of the module name to each function type system metadata, ensuring unique type systems across modules and preventing aliasing errors. This resolves #1458.