[llvm] Add flags to dump IR to a file before and after LLVM passes (PR #65179)

[Nuri Amari via llvm-commits]

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@@ -0,0 +1,71 @@
+; RUN: mkdir -p %t/logs
+; RUN: rm -rf %t/logs
+
+; Basic dump before and after a single module pass
+; RUN: opt %s -disable-output -passes='no-op-module' -ir-dump-directory %t/logs -dump-after=no-op-module -dump-before=no-op-module
+; RUN: find %t/logs -type f -print | FileCheck %s --check-prefix=SINGLE-RUN -DSOURCE_FILE_NAME=%s
+; SINGLE-RUN-DAG: [[SOURCE_FILE_NAME]]/0.NoOpModulePass.0-before.ll
+; SINGLE-RUN-DAG: [[SOURCE_FILE_NAME]]/0.NoOpModulePass.0-after.ll
+; RUN: rm -rf %t/logs
+
+; Dump before and after multiple runs of the same module pass
+; RUN: opt %s -disable-output -passes='no-op-module,no-op-module,no-op-module' -ir-dump-directory %t/logs -dump-after=no-op-module -dump-before=no-op-module
+; RUN: find %t/logs -type f -print | FileCheck %s --check-prefix=MULTIPLE-RUNS -DSOURCE_FILE_NAME=%s
+; MULTIPLE-RUNS-DAG: [[SOURCE_FILE_NAME]]/0.NoOpModulePass.0-before.ll
+; MULTIPLE-RUNS-DAG: [[SOURCE_FILE_NAME]]/0.NoOpModulePass.0-after.ll
+; MULTIPLE-RUNS-DAG: [[SOURCE_FILE_NAME]]/1.NoOpModulePass.1-before.ll
+; MULTIPLE-RUNS-DAG: [[SOURCE_FILE_NAME]]/1.NoOpModulePass.1-after.ll
+; MULTIPLE-RUNS-DAG: [[SOURCE_FILE_NAME]]/2.NoOpModulePass.2-before.ll
+; MULTIPLE-RUNS-DAG: [[SOURCE_FILE_NAME]]/2.NoOpModulePass.2-after.ll
+; RUN: rm -rf %t/logs
+
+; Dump before and after multiple passes, some nested
+; RUN: opt %s -disable-output -passes='no-op-module,function(no-op-function),function(loop(no-op-loop)),no-op-module' -ir-dump-directory %t/logs -dump-after=no-op-module,no-op-function,no-op-loop -dump-before=no-op-module,no-op-function,no-op-loop
+; RUN: find %t/logs -type f -print | FileCheck %s --check-prefix=MULTIPLE-NESTED-RUNS -DSOURCE_FILE_NAME=%s
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/0.NoOpModulePass.0-before.ll
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/0.NoOpModulePass.0-after.ll
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/1.ModuleToFunctionPassAdaptor.0/0.PassManager<llvm::Function>.0/0.NoOpFunctionPass.0-before.ll
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/1.ModuleToFunctionPassAdaptor.0/0.PassManager<llvm::Function>.0/0.NoOpFunctionPass.0-after.ll
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/1.ModuleToFunctionPassAdaptor.0/1.PassManager<llvm::Function>.1/0.NoOpFunctionPass.0-before.ll
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/1.ModuleToFunctionPassAdaptor.0/1.PassManager<llvm::Function>.1/0.NoOpFunctionPass.0-after.ll
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/2.ModuleToFunctionPassAdaptor.1/1.PassManager<llvm::Function>.1/0.FunctionToLoopPassAdaptor.0/1.PassManager<llvm::Loop, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>.0/0.NoOpLoopPass.0-before.ll
+; MULTIPLE-NESTED-RUNS-DAG: [[SOURCE_FILE_NAME]]/2.ModuleToFunctionPassAdaptor.1/1.PassManager<llvm::Function>.1/0.FunctionToLoopPassAdaptor.0/1.PassManager<llvm::Loop, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>.0/0.NoOpLoopPass.0-after.ll
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NuriAmari wrote:

Surely a less verbose pass name than `PassManager<llvm::Loop, llvm::AnalysisManager<llvm::Loop, llvm::LoopStandardAnalysisResults&>, llvm::LoopStandardAnalysisResults&, llvm::LPMUpdater&>` is achievable, but I'm not sure how to best go about that.

https://github.com/llvm/llvm-project/pull/65179