3 files changed, 38 insertions, 0 deletions
diff --git a/src/pass.h b/src/pass.h
index 36d49f7b7..973773c49 100644
--- a/src/pass.h
+++ b/src/pass.h
@@ -226,6 +226,8 @@ struct PassOptions {
   // Arbitrary string arguments from the commandline, which we forward to
   // passes.
   std::unordered_map<std::string, std::string> arguments;
+  // Passes to skip and not run.
+  std::unordered_set<std::string> passesToSkip;
 
   // Effect info computed for functions. One pass can generate this and then
   // other passes later can benefit from it. It is up to the sequence of passes
@@ -386,6 +388,9 @@ private:
   // Whether this pass runner has run. A pass runner should only be run once.
   bool ran = false;
 
+  // Passes in |options.passesToSkip| that we have seen and skipped.
+  std::unordered_set<std::string> skippedPasses;
+
   void runPass(Pass* pass);
   void runPassOnFunction(Pass* pass, Function* func);
 
diff --git a/src/passes/pass.cpp b/src/passes/pass.cpp
index 373322a51..593023c7c 100644
--- a/src/passes/pass.cpp
+++ b/src/passes/pass.cpp
@@ -692,6 +692,9 @@ void PassRunner::run() {
   assert(!ran);
   ran = true;
 
+  // As we run passes, we'll notice which we skip.
+  skippedPasses.clear();
+
   static const int passDebug = getPassDebug();
   // Emit logging information when asked for. At passDebug level 1+ we log
   // the main passes, while in 2 we also log nested ones. Note that for
@@ -812,6 +815,16 @@ void PassRunner::run() {
     }
     flush();
   }
+
+  // All the passes the user requested to skip should have been seen, and
+  // skipped. If not, the user may have had a typo in the name of a pass to
+  // skip, and we will warn.
+  for (auto pass : options.passesToSkip) {
+    if (!skippedPasses.count(pass)) {
+      std::cerr << "warning: --" << pass << " was requested to be skipped, "
+                << "but it was not found in the passes that were run.\n";
+    }
+  }
 }
 
 void PassRunner::runOnFunction(Function* func) {
@@ -930,6 +943,13 @@ struct AfterEffectModuleChecker {
 };
 
 void PassRunner::runPass(Pass* pass) {
+  assert(!pass->isFunctionParallel());
+
+  if (options.passesToSkip.count(pass->name)) {
+    skippedPasses.insert(pass->name);
+    return;
+  }
+
   std::unique_ptr<AfterEffectModuleChecker> checker;
   if (getPassDebug()) {
     checker = std::unique_ptr<AfterEffectModuleChecker>(
@@ -949,6 +969,11 @@ void PassRunner::runPass(Pass* pass) {
 void PassRunner::runPassOnFunction(Pass* pass, Function* func) {
   assert(pass->isFunctionParallel());
 
+  if (options.passesToSkip.count(pass->name)) {
+    skippedPasses.insert(pass->name);
+    return;
+  }
+
   auto passDebug = getPassDebug();
 
   // Add extra validation logic in pass-debug mode 2. The main logic in
diff --git a/src/tools/optimization-options.h b/src/tools/optimization-options.h
index 698d3305e..c87530536 100644
--- a/src/tools/optimization-options.h
+++ b/src/tools/optimization-options.h
@@ -277,6 +277,14 @@ struct OptimizationOptions : public ToolOptions {
            Options::Arguments::Zero,
            [this](Options*, const std::string&) {
              passOptions.zeroFilledMemory = true;
+           })
+      .add("--skip-pass",
+           "-sp",
+           "Skip a pass (do not run it)",
+           OptimizationOptionsCategory,
+           Options::Arguments::One,
+           [this](Options*, const std::string& pass) {
+             passOptions.passesToSkip.insert(pass);
            });
 
     // add passes in registry