[CodeGen] Support start/stop in CodeGenPassBuilder (#70912)

Add `-start/stop-before/after` support for CodeGenPassBuilder.
Part of #69879.

1 files changed, 34 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/TargetPassConfig.cpp b/llvm/lib/CodeGen/TargetPassConfig.cpp
index 3bbc792..52cf6b84 100644
--- a/llvm/lib/CodeGen/TargetPassConfig.cpp
+++ b/llvm/lib/CodeGen/TargetPassConfig.cpp
@@ -609,6 +609,40 @@ void llvm::registerCodeGenCallback(PassInstrumentationCallbacks &PIC,
   registerPartialPipelineCallback(PIC, LLVMTM);
 }
 
+Expected<TargetPassConfig::StartStopInfo>
+TargetPassConfig::getStartStopInfo(PassInstrumentationCallbacks &PIC) {
+  auto [StartBefore, StartBeforeInstanceNum] =
+      getPassNameAndInstanceNum(StartBeforeOpt);
+  auto [StartAfter, StartAfterInstanceNum] =
+      getPassNameAndInstanceNum(StartAfterOpt);
+  auto [StopBefore, StopBeforeInstanceNum] =
+      getPassNameAndInstanceNum(StopBeforeOpt);
+  auto [StopAfter, StopAfterInstanceNum] =
+      getPassNameAndInstanceNum(StopAfterOpt);
+
+  if (!StartBefore.empty() && !StartAfter.empty())
+    return make_error<StringError>(
+        Twine(StartBeforeOptName) + " and " + StartAfterOptName + " specified!",
+        std::make_error_code(std::errc::invalid_argument));
+  if (!StopBefore.empty() && !StopAfter.empty())
+    return make_error<StringError>(
+        Twine(StopBeforeOptName) + " and " + StopAfterOptName + " specified!",
+        std::make_error_code(std::errc::invalid_argument));
+
+  StartStopInfo Result;
+  Result.StartPass = StartBefore.empty() ? StartAfter : StartBefore;
+  Result.StopPass = StopBefore.empty() ? StopAfter : StopBefore;
+  Result.StartInstanceNum =
+      StartBefore.empty() ? StartAfterInstanceNum : StartBeforeInstanceNum;
+  Result.StopInstanceNum =
+      StopBefore.empty() ? StopAfterInstanceNum : StopBeforeInstanceNum;
+  Result.StartAfter = !StartAfter.empty();
+  Result.StopAfter = !StopAfter.empty();
+  Result.StartInstanceNum += Result.StartInstanceNum == 0;
+  Result.StopInstanceNum += Result.StopInstanceNum == 0;
+  return Result;
+}
+
 // Out of line constructor provides default values for pass options and
 // registers all common codegen passes.
 TargetPassConfig::TargetPassConfig(LLVMTargetMachine &TM, PassManagerBase &pm)