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

[Nuri Amari via cfe-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:

I made an attempt at this, the trouble is the new PM instrumentation infrastructure only provides callbacks with the PassID, which is this verbose sometimes. The existing Class name to pass name mapping does not contain entries for all passes (ex. adaptors and PMs). 

I think more consistent names are doable, but perhaps something for another patch.

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