From 46a52ff9eda0750ff05311310774d954bcaf3408 Mon Sep 17 00:00:00 2001
From: Eli Friedman <efriedma@quicinc.com>
Date: Tue, 21 Apr 2020 21:00:19 -0700
Subject: [PATCH] [TargetPassConfig] Run MachineVerifier after more passes.

We were disabling verification for no reason in a bunch of places; just
turn it on.

At this point, there are two key places where we don't run verification:
during register allocation, and after addPreEmitPass.  Regalloc probably
isn't worth messing with; it has its own invariants, and verifying
afterwards is probably good enough.  For after addPreEmitPass, it's
probably worth investigating improvements.
---
 llvm/lib/CodeGen/TargetPassConfig.cpp | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/llvm/lib/CodeGen/TargetPassConfig.cpp b/llvm/lib/CodeGen/TargetPassConfig.cpp
index 336b1a8..4432c3f 100644
--- a/llvm/lib/CodeGen/TargetPassConfig.cpp
+++ b/llvm/lib/CodeGen/TargetPassConfig.cpp
@@ -934,7 +934,7 @@ void TargetPassConfig::addMachinePasses() {
   } else {
     // If the target requests it, assign local variables to stack slots relative
     // to one another and simplify frame index references where possible.
-    addPass(&LocalStackSlotAllocationID, false);
+    addPass(&LocalStackSlotAllocationID);
   }
 
   if (TM->Options.EnableIPRA)
@@ -1006,10 +1006,10 @@ void TargetPassConfig::addMachinePasses() {
     addBlockPlacement();
 
   // Insert before XRay Instrumentation.
-  addPass(&FEntryInserterID, false);
+  addPass(&FEntryInserterID);
 
-  addPass(&XRayInstrumentationID, false);
-  addPass(&PatchableFunctionID, false);
+  addPass(&XRayInstrumentationID);
+  addPass(&PatchableFunctionID);
 
   addPreEmitPass();
 
@@ -1018,6 +1018,8 @@ void TargetPassConfig::addMachinePasses() {
     // clobbered registers, to be used to optimize call sites.
     addPass(createRegUsageInfoCollector());
 
+  // FIXME: Some backends are incompatible with running the verifier after
+  // addPreEmitPass.  Maybe only pass "false" here for those targets?
   addPass(&FuncletLayoutID, false);
 
   addPass(&StackMapLivenessID, false);
@@ -1048,15 +1050,15 @@ void TargetPassConfig::addMachineSSAOptimization() {
 
   // Optimize PHIs before DCE: removing dead PHI cycles may make more
   // instructions dead.
-  addPass(&OptimizePHIsID, false);
+  addPass(&OptimizePHIsID);
 
   // This pass merges large allocas. StackSlotColoring is a different pass
   // which merges spill slots.
-  addPass(&StackColoringID, false);
+  addPass(&StackColoringID);
 
   // If the target requests it, assign local variables to stack slots relative
   // to one another and simplify frame index references where possible.
-  addPass(&LocalStackSlotAllocationID, false);
+  addPass(&LocalStackSlotAllocationID);
 
   // With optimization, dead code should already be eliminated. However
   // there is one known exception: lowered code for arguments that are only
@@ -1069,8 +1071,8 @@ void TargetPassConfig::addMachineSSAOptimization() {
   // loop info, just like LICM and CSE below.
   addILPOpts();
 
-  addPass(&EarlyMachineLICMID, false);
-  addPass(&MachineCSEID, false);
+  addPass(&EarlyMachineLICMID);
+  addPass(&MachineCSEID);
 
   addPass(&MachineSinkingID);
 
-- 
2.7.4