[opt] Rename -enable-new-pm -> -bugpoint-enable-legacy-pm

-enable-new-pm is no longer necessary except for bugpoint. Make the name more clunky so it hopefully won't be used.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D146103

Author: aeubanks

llvm/docs/NewPassManager.rst

@@ -420,17 +420,6 @@ for more details.
 Invoking ``opt``
 ================
 
-To use the legacy pass manager:
-
-.. code-block:: shell
-
-  $ opt -enable-new-pm=0 -pass1 -pass2 /tmp/a.ll -S
-
-This will be removed once the legacy pass manager is deprecated and removed for
-the optimization pipeline.
-
-To use the new PM:
-
 .. code-block:: shell
 
   $ opt -passes='pass1,pass2' /tmp/a.ll -S

llvm/docs/WritingAnLLVMPass.rst

@@ -36,11 +36,10 @@ advanced features are discussed.
 
 .. warning::
   This document deals with the legacy pass manager. LLVM uses the new pass
-  manager by default for the optimization pipeline (the codegen pipeline is
-  still using the legacy pass manager), which has its own way of defining
+  manager for the optimization pipeline (the codegen pipeline
+  still uses the legacy pass manager), which has its own way of defining
   passes. For more details, see :doc:`WritingAnLLVMNewPMPass` and
-  :doc:`NewPassManager`. To use the legacy pass manager with ``opt``, pass
-  the ``-enable-new-pm=0`` flag to all ``opt`` invocations.
+  :doc:`NewPassManager`.
 
 Quick Start --- Writing hello world
 ===================================

llvm/test/BugPoint/unsymbolized.ll

@@ -3,7 +3,7 @@
 ; RUN: echo "print('args = ' + str(sys.argv))" >> %t.py
 ; RUN: echo "exit(1)" >> %t.py
 ; RUN: not bugpoint -load %llvmshlibdir/BugpointPasses%pluginext %s -output-prefix %t -bugpoint-crashcalls -opt-command=%python -opt-args %t.py | FileCheck %s
-; RUN: not --crash opt -enable-new-pm=0 -load %llvmshlibdir/BugpointPasses%pluginext %s -bugpoint-crashcalls -disable-symbolication 2>&1 | FileCheck --check-prefix=CRASH %s
+; RUN: not --crash opt -bugpoint-enable-legacy-pm -load %llvmshlibdir/BugpointPasses%pluginext %s -bugpoint-crashcalls -disable-symbolication 2>&1 | FileCheck --check-prefix=CRASH %s
 ; RUN: not bugpoint -load %llvmshlibdir/BugpointPasses%pluginext %s -output-prefix %t -bugpoint-crashcalls -opt-command=%t.non.existent.opt.binary -opt-args %t.py 2>&1 | FileCheck %s --check-prefix=BAD-OPT
 
 ; Test that bugpoint disables symbolication on the opt tool to reduce runtime overhead when opt crashes

llvm/test/Feature/load_extension.ll

@@ -7,10 +7,6 @@
 ; REQUIRES: plugins, examples
 ; UNSUPPORTED: target={{.*windows.*}}
 ; CHECK: Bye
-;
-; Specifying a new PM pass plugin with the old PM is an error.
-; RUN: ! opt %s %loadnewpmbye -goodbye -wave-goodbye -disable-output -enable-new-pm=0 2>&1 | FileCheck %s --check-prefix=ERROR
-; ERROR: load-pass-plugin specified with legacy PM.
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"

llvm/test/Other/opt-On.ll

@@ -19,16 +19,3 @@ define void @f() {
   unreachable
 }
 
-
-; Legacy PM deprecation tests (tests should be removed in the future).
-;
-; RUN: not opt -enable-new-pm=0 -O0 < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-; RUN: not opt -enable-new-pm=0 -O1 < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-; RUN: not opt -enable-new-pm=0 -O2 < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-; RUN: not opt -enable-new-pm=0 -O3 < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-; RUN: not opt -enable-new-pm=0 -Os < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-; RUN: not opt -enable-new-pm=0 -Oz < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-; RUN: not opt -O1 -codegenprepare < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-; RUN: not opt -codegenprepare -O2 < %s -S 2>&1 | FileCheck %s --check-prefix=LEGACYPM-ERROR
-
-; LEGACYPM-ERROR: Cannot use -O# with legacy PM

llvm/test/Other/opt-legacy-syntax-deprecation.ll

@@ -4,7 +4,6 @@
 ; RUN: opt /dev/null -disable-output -passes=instcombine 2>&1 | FileCheck %s --check-prefix=OK --allow-empty
 ; RUN: not opt /dev/null -disable-output -instcombine 2>&1 | FileCheck %s --check-prefix=WARN
 ; RUN: not opt /dev/null -disable-output -instcombine -always-inline 2>&1 | FileCheck %s --check-prefix=WARN
-; RUN: opt /dev/null -disable-output -instcombine -enable-new-pm=0 2>&1 | FileCheck %s --check-prefix=OK --allow-empty
 ; RUN: opt /dev/null -disable-output -codegenprepare -mtriple=x86_64-unknown-linux-gnu 2>&1 | FileCheck %s --check-prefix=OK --allow-empty
 
 ; OK-NOT: deprecated

llvm/tools/bugpoint/OptimizerDriver.cpp

@@ -207,7 +207,7 @@ bool BugDriver::runPasses(Module &Program,
     Args.push_back(OptArgs[i]);
   // Pin to legacy PM since bugpoint has lots of infra and hacks revolving
   // around the legacy PM.
-  Args.push_back("-enable-new-pm=0");
+  Args.push_back("-bugpoint-enable-legacy-pm");
   Args.push_back("-disable-symbolication");
   Args.push_back("-o");
   Args.push_back(OutputFilename);

llvm/tools/opt/opt.cpp

@@ -68,12 +68,12 @@ static codegen::RegisterCodeGenFlags CFG;
 static cl::list<const PassInfo *, bool, PassNameParser> PassList(cl::desc(
     "Optimizations available (use '-passes=' for the new pass manager)"));
 
-static cl::opt<bool> EnableNewPassManager(
-    "enable-new-pm",
-    cl::desc("Enable the new pass manager, translating "
-             "'opt -foo' to 'opt -passes=foo'. This is strictly for the new PM "
-             "migration, use '-passes=' when possible."),
-    cl::init(true));
+static cl::opt<bool> EnableLegacyPassManager(
+    "bugpoint-enable-legacy-pm",
+    cl::desc(
+        "Enable the legacy pass manager. This is strictly for bugpoint "
+        "due to it not working with the new PM, please do not use otherwise."),
+    cl::init(false));
 
 // This flag specifies a textual description of the optimization pass pipeline
 // to run over the module. This flag switches opt to use the new pass manager
@@ -485,11 +485,8 @@ int main(int argc, char **argv) {
 
   LLVMContext Context;
 
-  // If `-passes=` is specified, use NPM.
-  // If `-enable-new-pm` is specified and there are no codegen passes, use NPM.
-  // e.g. `-enable-new-pm -sroa` will use NPM.
-  // but `-enable-new-pm -codegenprepare` will still revert to legacy PM.
-  const bool UseNPM = (EnableNewPassManager && !shouldForceLegacyPM()) ||
+  // TODO: remove shouldForceLegacyPM().
+  const bool UseNPM = (!EnableLegacyPassManager && !shouldForceLegacyPM()) ||
                       PassPipeline.getNumOccurrences() > 0;
 
   if (UseNPM && !PassList.empty()) {