[IPConstProp] Replace and move tests to SCCP.

[fhahn]

Summary

As far as I know, ipconstprop has not been used in years and ipsccp has
been used instead. This has the potential for confusion and sometimes
leads people to spend time finding & reporting bugs as well as
updating it to work with the latest API changes.

This patch moves the tests over to SCCP. There's one functional difference
I am aware of: ipconstprop propagates for each call-site individually, so
for functions that are called with different constant arguments it can sometimes
produce better results than ipsccp (at much higher compile-time cost).But
IPSCCP can be thought to do so as well for internal functions and as mentioned
earlier, the pass seems unused in practice (and there are no plans on working
towards enabling it anytime).

[xbolva00]

Maybe ask llvm community on mailing list for permission to remove it from codebase?

[xbolva00]

llvm/test/Transforms/IPConstantProp/multiple_callbacks.ll

2

Missing run line?

llvm/test/Transforms/IPConstantProp/return-argument.ll

56

It would be useful to handle this too

[fhahn]

In D84447#2170073, @xbolva00 wrote:

Maybe ask llvm community on mailing list for permission to remove it from codebase?

I replied to a thread with that suggestion (http://lists.llvm.org/pipermail/llvm-dev/2020-July/143703.html). Let's see if there are any obvious things I am missing. Happy to send a heads-up to the list after that.

[jdoerfert]

FWIW, I'm in favor of deleting this.

[nikic]

It looks like a lot of the tests here are about !callback support.

[jdoerfert]

In D84447#2170176, @nikic wrote:

It looks like a lot of the tests here are about !callback support.

Yes. Pre-Attributor callbacks were only supported by this pass. These tests are subsumed by the Attributor test and Attributor interprets !callback. That said, removing those tests for SCCP is fine with me. Keeping them as "negative" test is as well.

[fhahn]

*actually* move the tests to the llvm/test/Transforms/SCCP.

As mentioned in the comments, there are 2 things IPSCCP does not support:

• !callback metadata - that should be straight forward to add (basically switching to abstract call site?)
• ipconstprop solves for each call site separately, so there can be more accurate results for callsites with constant arguments, at cost of (a lot of) compile-time. We could also do something similar in IPSCCP, but have to evaluate if the benefit warrants to extra compile-time. A quick sketch D84521

However I don't think any of the above should block removing ipconstprop, unless there are some real users.

[jdoerfert]

LGTM. Assuming no one using this comes forward.

[fhahn]

Thanks, so far there have been no objections on llvm-dev (http://lists.llvm.org/pipermail/llvm-dev/2020-July/143773.html) I'll land this soon. We can always bring it back again.

[MaskRay]

It was a hindsight, but moving the tests/deleting the pass could have been done with separate patches.

llvm/bindings/go/llvm/transforms_ipo.go

 
 func (pm PassManager) AddArgumentPromotionPass()     { C.LLVMAddArgumentPromotionPass(pm.C) }
 func (pm PassManager) AddConstantMergePass()         { C.LLVMAddConstantMergePass(pm.C) }
 func (pm PassManager) AddDeadArgEliminationPass()    { C.LLVMAddDeadArgEliminationPass(pm.C) }
 func (pm PassManager) AddFunctionAttrsPass()         { C.LLVMAddFunctionAttrsPass(pm.C) }
 func (pm PassManager) AddFunctionInliningPass()      { C.LLVMAddFunctionInliningPass(pm.C) }
 func (pm PassManager) AddGlobalDCEPass()             { C.LLVMAddGlobalDCEPass(pm.C) }
 func (pm PassManager) AddGlobalOptimizerPass()       { C.LLVMAddGlobalOptimizerPass(pm.C) }
-func (pm PassManager) AddIPConstantPropagationPass() { C.LLVMAddIPConstantPropagationPass(pm.C) }
 func (pm PassManager) AddPruneEHPass()               { C.LLVMAddPruneEHPass(pm.C) }
 func (pm PassManager) AddIPSCCPPass()                { C.LLVMAddIPSCCPPass(pm.C) }
 func (pm PassManager) AddInternalizePass(allButMain bool) {
   C.LLVMAddInternalizePass(pm.C, boolToUnsigned(allButMain))
 }
 func (pm PassManager) AddStripDeadPrototypesPass() { C.LLVMAddStripDeadPrototypesPass(pm.C) }

llvm/bindings/ocaml/transforms/ipo/ipo_ocaml.c

 
 /* [`Module] Llvm.PassManager.t -> unit */
 CAMLprim value llvm_add_global_optimizer(LLVMPassManagerRef PM) {
   LLVMAddGlobalOptimizerPass(PM);
   return Val_unit;
 }
 
 /* [`Module] Llvm.PassManager.t -> unit */
-CAMLprim value llvm_add_ip_constant_propagation(LLVMPassManagerRef PM) {
-  LLVMAddIPConstantPropagationPass(PM);
-  return Val_unit;
-}
-
-/* [`Module] Llvm.PassManager.t -> unit */
 CAMLprim value llvm_add_prune_eh(LLVMPassManagerRef PM) {
   LLVMAddPruneEHPass(PM);
   return Val_unit;
 }
 
 /* [`Module] Llvm.PassManager.t -> unit */
 CAMLprim value llvm_add_ipsccp(LLVMPassManagerRef PM) {
   LLVMAddIPSCCPPass(PM);

llvm/bindings/ocaml/transforms/ipo/llvm_ipo.mli

external add_global_dce
   : [ `Module ] Llvm.PassManager.t -> unit
   = "llvm_add_global_dce"
 
 (** See the [llvm::createGlobalOptimizerPass] function. *)
 external add_global_optimizer
   : [ `Module ] Llvm.PassManager.t -> unit
   = "llvm_add_global_optimizer"
 
-(** See the [llvm::createIPConstantPropagationPass] function. *)
-external add_ipc_propagation
-  : [ `Module ] Llvm.PassManager.t -> unit
-  = "llvm_add_ip_constant_propagation"
-
 (** See the [llvm::createPruneEHPass] function. *)
 external add_prune_eh
   : [ `Module ] Llvm.PassManager.t -> unit
   = "llvm_add_prune_eh"
 
 (** See the [llvm::createIPSCCPPass] function. *)
 external add_ipsccp
   : [ `Module ] Llvm.PassManager.t -> unit

llvm/docs/Passes.rst

 
 ``-internalize``: Internalize Global Symbols
 --------------------------------------------
 
 This pass loops over all of the functions in the input module, looking for a
 main function.  If a main function is found, all other functions and all global
 variables with initializers are marked as internal.
 
-``-ipconstprop``: Interprocedural constant propagation
-------------------------------------------------------
-
-This pass implements an *extremely* simple interprocedural constant propagation
-pass.  It could certainly be improved in many different ways, like using a
-worklist.  This pass makes arguments dead, but does not remove them.  The
-existing dead argument elimination pass should be run after this to clean up
-the mess.
-
 ``-ipsccp``: Interprocedural Sparse Conditional Constant Propagation
 --------------------------------------------------------------------
 
 An interprocedural variant of :ref:`Sparse Conditional Constant Propagation
 <passes-sccp>`.
 
 ``-jump-threading``: Jump Threading
 -----------------------------------

llvm/include/llvm-c/Transforms/IPO.h

 void LLVMAddAlwaysInlinerPass(LLVMPassManagerRef PM);
 
 /** See llvm::createGlobalDCEPass function. */
 void LLVMAddGlobalDCEPass(LLVMPassManagerRef PM);
 
 /** See llvm::createGlobalOptimizerPass function. */
 void LLVMAddGlobalOptimizerPass(LLVMPassManagerRef PM);
 
-/** See llvm::createIPConstantPropagationPass function. */
-void LLVMAddIPConstantPropagationPass(LLVMPassManagerRef PM);
-
 /** See llvm::createPruneEHPass function. */
 void LLVMAddPruneEHPass(LLVMPassManagerRef PM);
 
 /** See llvm::createIPSCCPPass function. */
 void LLVMAddIPSCCPPass(LLVMPassManagerRef PM);
 
 /** See llvm::createInternalizePass function. */
 void LLVMAddInternalizePass(LLVMPassManagerRef, unsigned AllButMain);

llvm/include/llvm/InitializePasses.h

 void initializeGlobalMergePass(PassRegistry&);
 void initializeGlobalOptLegacyPassPass(PassRegistry&);
 void initializeGlobalSplitPass(PassRegistry&);
 void initializeGlobalsAAWrapperPassPass(PassRegistry&);
 void initializeGuardWideningLegacyPassPass(PassRegistry&);
 void initializeHardwareLoopsPass(PassRegistry&);
 void initializeHotColdSplittingLegacyPassPass(PassRegistry&);
 void initializeHWAddressSanitizerLegacyPassPass(PassRegistry &);
-void initializeIPCPPass(PassRegistry&);
 void initializeIPSCCPLegacyPassPass(PassRegistry&);
 void initializeIRCELegacyPassPass(PassRegistry&);
 void initializeIRTranslatorPass(PassRegistry&);
 void initializeIVUsersWrapperPassPass(PassRegistry&);
 void initializeIfConverterPass(PassRegistry&);
 void initializeImmutableModuleSummaryIndexWrapperPassPass(PassRegistry&);
 void initializeImplicitNullChecksPass(PassRegistry&);
 void initializeIndVarSimplifyLegacyPassPass(PassRegistry&);

llvm/include/llvm/LinkAllPasses.h

ForcePassLinking() {
       (void) llvm::createFunctionImportPass();
       (void) llvm::createFunctionInliningPass();
       (void) llvm::createAlwaysInlinerLegacyPass();
       (void) llvm::createGlobalDCEPass();
       (void) llvm::createGlobalOptimizerPass();
       (void) llvm::createGlobalsAAWrapperPass();
       (void) llvm::createGuardWideningPass();
       (void) llvm::createLoopGuardWideningPass();
-      (void) llvm::createIPConstantPropagationPass();
       (void) llvm::createIPSCCPPass();
       (void) llvm::createInductiveRangeCheckEliminationPass();
       (void) llvm::createIndVarSimplifyPass();
       (void) llvm::createInstSimplifyLegacyPass();
       (void) llvm::createInstructionCombiningPass();
       (void) llvm::createInternalizePass();
       (void) llvm::createLCSSAPass();
       (void) llvm::createLegacyDivergenceAnalysisPass();

llvm/include/llvm/Transforms/IPO.h

 ///
 Pass *createArgumentPromotionPass(unsigned maxElements = 3);
 
 //===----------------------------------------------------------------------===//
 /// createOpenMPOptLegacyPass - OpenMP specific optimizations.
 Pass *createOpenMPOptLegacyPass();
 
 //===----------------------------------------------------------------------===//
-/// createIPConstantPropagationPass - This pass propagates constants from call
-/// sites into the bodies of functions.
-///
-ModulePass *createIPConstantPropagationPass();
-
-//===----------------------------------------------------------------------===//
 /// createIPSCCPPass - This pass propagates constants from call sites into the
 /// bodies of functions, and keeps track of whether basic blocks are executable
 /// in the process.
 ///
 ModulePass *createIPSCCPPass();
 
 //===----------------------------------------------------------------------===//
 //

llvm/lib/Transforms/IPO/CMakeLists.txt

add_llvm_component_library(LLVMipo
   ExtractGV.cpp
   ForceFunctionAttrs.cpp
   FunctionAttrs.cpp
   FunctionImport.cpp
   GlobalDCE.cpp
   GlobalOpt.cpp
   GlobalSplit.cpp
   HotColdSplitting.cpp
-  IPConstantPropagation.cpp
   IPO.cpp
   InferFunctionAttrs.cpp
   InlineSimple.cpp
   Inliner.cpp
   Internalize.cpp
   LoopExtractor.cpp
   LowerTypeTests.cpp
   MergeFunctions.cpp

llvm/lib/Transforms/IPO/IPConstantPropagation.cpp

-//===-- IPConstantPropagation.cpp - Propagate constants through calls -----===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// This pass implements an _extremely_ simple interprocedural constant
-// propagation pass.  It could certainly be improved in many different ways,
-// like using a worklist.  This pass makes arguments dead, but does not remove
-// them.  The existing dead argument elimination pass should be run after this
-// to clean up the mess.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/Statistic.h"
-#include "llvm/Analysis/ValueTracking.h"
-#include "llvm/IR/AbstractCallSite.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/Module.h"
-#include "llvm/InitializePasses.h"
-#include "llvm/Pass.h"
-#include "llvm/Transforms/IPO.h"
-using namespace llvm;
-
-#define DEBUG_TYPE "ipconstprop"
-
-STATISTIC(NumArgumentsProped, "Number of args turned into constants");
-STATISTIC(NumReturnValProped, "Number of return values turned into constants");
-
-namespace {
-  /// IPCP - The interprocedural constant propagation pass
-  ///
-  struct IPCP : public ModulePass {
-    static char ID; // Pass identification, replacement for typeid
-    IPCP() : ModulePass(ID) {
-      initializeIPCPPass(*PassRegistry::getPassRegistry());
-    }
-
-    bool runOnModule(Module &M) override;
-  };
-}
-
-/// PropagateConstantsIntoArguments - Look at all uses of the specified
-/// function.  If all uses are direct call sites, and all pass a particular
-/// constant in for an argument, propagate that constant in as the argument.
-///
-static bool PropagateConstantsIntoArguments(Function &F) {
-  if (F.arg_empty() || F.use_empty()) return false; // No arguments? Early exit.
-
-  // For each argument, keep track of its constant value and whether it is a
-  // constant or not.  The bool is driven to true when found to be non-constant.
-  SmallVector<PointerIntPair<Constant *, 1, bool>, 16> ArgumentConstants;
-  ArgumentConstants.resize(F.arg_size());
-
-  unsigned NumNonconstant = 0;
-  for (Use &U : F.uses()) {
-    User *UR = U.getUser();
-    // Ignore blockaddress uses.
-    if (isa<BlockAddress>(UR)) continue;
-
-    // If no abstract call site was created we did not understand the use, bail.
-    AbstractCallSite ACS(&U);
-    if (!ACS)
-      return false;
-
-    // Mismatched argument count is undefined behavior. Simply bail out to avoid
-    // handling of such situations below (avoiding asserts/crashes).
-    unsigned NumActualArgs = ACS.getNumArgOperands();
-    if (F.isVarArg() ? ArgumentConstants.size() > NumActualArgs
-                     : ArgumentConstants.size() != NumActualArgs)
-      return false;
-
-    // Check out all of the potentially constant arguments.  Note that we don't
-    // inspect varargs here.
-    Function::arg_iterator Arg = F.arg_begin();
-    for (unsigned i = 0, e = ArgumentConstants.size(); i != e; ++i, ++Arg) {
-
-      // If this argument is known non-constant, ignore it.
-      if (ArgumentConstants[i].getInt())
-        continue;
-
-      Value *V = ACS.getCallArgOperand(i);
-      Constant *C = dyn_cast_or_null<Constant>(V);
-
-      // Mismatched argument type is undefined behavior. Simply bail out to avoid
-      // handling of such situations below (avoiding asserts/crashes).
-      if (C && Arg->getType() != C->getType())
-        return false;
-
-      // We can only propagate thread independent values through callbacks.
-      // This is different to direct/indirect call sites because for them we
-      // know the thread executing the caller and callee is the same. For
-      // callbacks this is not guaranteed, thus a thread dependent value could
-      // be different for the caller and callee, making it invalid to propagate.
-      if (C && ACS.isCallbackCall() && C->isThreadDependent()) {
-        // Argument became non-constant. If all arguments are non-constant now,
-        // give up on this function.
-        if (++NumNonconstant == ArgumentConstants.size())
-          return false;
-
-        ArgumentConstants[i].setInt(true);
-        continue;
-      }
-
-      if (C && ArgumentConstants[i].getPointer() == nullptr) {
-        ArgumentConstants[i].setPointer(C); // First constant seen.
-      } else if (C && ArgumentConstants[i].getPointer() == C) {
-        // Still the constant value we think it is.
-      } else if (V == &*Arg) {
-        // Ignore recursive calls passing argument down.
-      } else {
-        // Argument became non-constant.  If all arguments are non-constant now,
-        // give up on this function.
-        if (++NumNonconstant == ArgumentConstants.size())
-          return false;
-        ArgumentConstants[i].setInt(true);
-      }
-    }
-  }
-
-  // If we got to this point, there is a constant argument!
-  assert(NumNonconstant != ArgumentConstants.size());
-  bool MadeChange = false;
-  Function::arg_iterator AI = F.arg_begin();
-  for (unsigned i = 0, e = ArgumentConstants.size(); i != e; ++i, ++AI) {
-    // Do we have a constant argument?
-    if (ArgumentConstants[i].getInt() || AI->use_empty() ||
-        (AI->hasByValAttr() && !F.onlyReadsMemory()))
-      continue;
-
-    Value *V = ArgumentConstants[i].getPointer();
-    if (!V) V = UndefValue::get(AI->getType());
-    AI->replaceAllUsesWith(V);
-    ++NumArgumentsProped;
-    MadeChange = true;
-  }
-  return MadeChange;
-}
-
-
-// Check to see if this function returns one or more constants. If so, replace
-// all callers that use those return values with the constant value. This will
-// leave in the actual return values and instructions, but deadargelim will
-// clean that up.
-//
-// Additionally if a function always returns one of its arguments directly,
-// callers will be updated to use the value they pass in directly instead of
-// using the return value.
-static bool PropagateConstantReturn(Function &F) {
-  if (F.getReturnType()->isVoidTy())
-    return false; // No return value.
-
-  // We can infer and propagate the return value only when we know that the
-  // definition we'll get at link time is *exactly* the definition we see now.
-  // For more details, see GlobalValue::mayBeDerefined.
-  if (!F.isDefinitionExact())
-    return false;
-
-  // Don't touch naked functions. The may contain asm returning
-  // value we don't see, so we may end up interprocedurally propagating
-  // the return value incorrectly.
-  if (F.hasFnAttribute(Attribute::Naked))
-    return false;
-
-  // Check to see if this function returns a constant.
-  SmallVector<Value *,4> RetVals;
-  StructType *STy = dyn_cast<StructType>(F.getReturnType());
-  if (STy)
-    for (unsigned i = 0, e = STy->getNumElements(); i < e; ++i)
-      RetVals.push_back(UndefValue::get(STy->getElementType(i)));
-  else
-    RetVals.push_back(UndefValue::get(F.getReturnType()));
-
-  unsigned NumNonConstant = 0;
-  for (BasicBlock &BB : F)
-    if (ReturnInst *RI = dyn_cast<ReturnInst>(BB.getTerminator())) {
-      for (unsigned i = 0, e = RetVals.size(); i != e; ++i) {
-        // Already found conflicting return values?
-        Value *RV = RetVals[i];
-        if (!RV)
-          continue;
-
-        // Find the returned value
-        Value *V;
-        if (!STy)
-          V = RI->getOperand(0);
-        else
-          V = FindInsertedValue(RI->getOperand(0), i);
-
-        if (V) {
-          // Ignore undefs, we can change them into anything
-          if (isa<UndefValue>(V))
-            continue;
-
-          // Try to see if all the rets return the same constant or argument.
-          if (isa<Constant>(V) || isa<Argument>(V)) {
-            if (isa<UndefValue>(RV)) {
-              // No value found yet? Try the current one.
-              RetVals[i] = V;
-              continue;
-            }
-            // Returning the same value? Good.
-            if (RV == V)
-              continue;
-          }
-        }
-        // Different or no known return value? Don't propagate this return
-        // value.
-        RetVals[i] = nullptr;
-        // All values non-constant? Stop looking.
-        if (++NumNonConstant == RetVals.size())
-          return false;
-      }
-    }
-
-  // If we got here, the function returns at least one constant value.  Loop
-  // over all users, replacing any uses of the return value with the returned
-  // constant.
-  bool MadeChange = false;
-  for (Use &U : F.uses()) {
-    CallBase *CB = dyn_cast<CallBase>(U.getUser());
-
-    // Not a call instruction or a call instruction that's not calling F
-    // directly?
-    if (!CB || !CB->isCallee(&U))
-      continue;
-
-    // Call result not used?
-    if (CB->use_empty())
-      continue;
-
-    MadeChange = true;
-
-    if (!STy) {
-      Value* New = RetVals[0];
-      if (Argument *A = dyn_cast<Argument>(New))
-        // Was an argument returned? Then find the corresponding argument in
-        // the call instruction and use that.
-        New = CB->getArgOperand(A->getArgNo());
-      CB->replaceAllUsesWith(New);
-      continue;
-    }
-
-    for (auto I = CB->user_begin(), E = CB->user_end(); I != E;) {
-      Instruction *Ins = cast<Instruction>(*I);
-
-      // Increment now, so we can remove the use
-      ++I;
-
-      // Find the index of the retval to replace with
-      int index = -1;
-      if (ExtractValueInst *EV = dyn_cast<ExtractValueInst>(Ins))
-        if (EV->getNumIndices() == 1)
-          index = *EV->idx_begin();
-
-      // If this use uses a specific return value, and we have a replacement,
-      // replace it.
-      if (index != -1) {
-        Value *New = RetVals[index];
-        if (New) {
-          if (Argument *A = dyn_cast<Argument>(New))
-            // Was an argument returned? Then find the corresponding argument in
-            // the call instruction and use that.
-            New = CB->getArgOperand(A->getArgNo());
-          Ins->replaceAllUsesWith(New);
-          Ins->eraseFromParent();
-        }
-      }
-    }
-  }
-
-  if (MadeChange) ++NumReturnValProped;
-  return MadeChange;
-}
-
-char IPCP::ID = 0;
-INITIALIZE_PASS(IPCP, "ipconstprop",
-                "Interprocedural constant propagation", false, false)
-
-ModulePass *llvm::createIPConstantPropagationPass() { return new IPCP(); }
-
-bool IPCP::runOnModule(Module &M) {
-  if (skipModule(M))
-    return false;
-
-  bool Changed = false;
-  bool LocalChange = true;
-
-  // FIXME: instead of using smart algorithms, we just iterate until we stop
-  // making changes.
-  while (LocalChange) {
-    LocalChange = false;
-    for (Function &F : M)
-      if (!F.isDeclaration()) {
-        // Delete any klingons.
-        F.removeDeadConstantUsers();
-        if (F.hasLocalLinkage())
-          LocalChange |= PropagateConstantsIntoArguments(F);
-        Changed |= PropagateConstantReturn(F);
-      }
-    Changed |= LocalChange;
-  }
-  return Changed;
-}

llvm/lib/Transforms/IPO/IPO.cpp

void llvm::initializeIPO(PassRegistry &Registry) {
   initializeCrossDSOCFIPass(Registry);
   initializeDAEPass(Registry);
   initializeDAHPass(Registry);
   initializeForceFunctionAttrsLegacyPassPass(Registry);
   initializeGlobalDCELegacyPassPass(Registry);
   initializeGlobalOptLegacyPassPass(Registry);
   initializeGlobalSplitPass(Registry);
   initializeHotColdSplittingLegacyPassPass(Registry);
-  initializeIPCPPass(Registry);
   initializeAlwaysInlinerLegacyPassPass(Registry);
   initializeSimpleInlinerPass(Registry);
   initializeInferFunctionAttrsLegacyPassPass(Registry);
   initializeInternalizeLegacyPassPass(Registry);
   initializeLoopExtractorPass(Registry);
   initializeBlockExtractorPass(Registry);
   initializeSingleLoopExtractorPass(Registry);
   initializeLowerTypeTestsPass(Registry);

 void LLVMAddGlobalDCEPass(LLVMPassManagerRef PM) {
   unwrap(PM)->add(createGlobalDCEPass());
 }
 
 void LLVMAddGlobalOptimizerPass(LLVMPassManagerRef PM) {
   unwrap(PM)->add(createGlobalOptimizerPass());
 }
 
-void LLVMAddIPConstantPropagationPass(LLVMPassManagerRef PM) {
-  unwrap(PM)->add(createIPConstantPropagationPass());
-}
-
 void LLVMAddPruneEHPass(LLVMPassManagerRef PM) {
   unwrap(PM)->add(createPruneEHPass());
 }
 
 void LLVMAddIPSCCPPass(LLVMPassManagerRef PM) {
   unwrap(PM)->add(createIPSCCPPass());
 }
 

llvm/test/Transforms/IPConstantProp/2008-06-09-WeakProp.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -S | FileCheck %s
+; RUN: opt < %s -ipsccp -S | FileCheck %s
 ; Should not propagate the result of a weak function.
 ; PR2411
 
 define weak i32 @foo() nounwind  {
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    ret i32 1
 ;

llvm/test/Transforms/IPConstantProp/PR43857.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -S -ipconstprop | FileCheck %s
+; RUN: opt < %s -S -ipsccp | FileCheck %s
 
 %struct.wobble = type { i32 }
 %struct.zot = type { %struct.wobble, %struct.wobble, %struct.wobble }
 
 declare dso_local fastcc float @bar(%struct.wobble* noalias, <8 x i32>) unnamed_addr
 
 define %struct.zot @widget(<8 x i32> %arg) local_unnamed_addr {
 ; CHECK-LABEL: @widget(
 ; CHECK-NEXT:  bb:
 ; CHECK-NEXT:    ret [[STRUCT_ZOT:%.*]] undef
 ;
 bb:
   ret %struct.zot undef
 }
 
 define void @baz(<8 x i32> %arg) local_unnamed_addr {
 ; CHECK-LABEL: @baz(
 ; CHECK-NEXT:  bb:
 ; CHECK-NEXT:    [[TMP:%.*]] = call [[STRUCT_ZOT:%.*]] @widget(<8 x i32> [[ARG:%.*]])
-; CHECK-NEXT:    [[TMP1:%.*]] = extractvalue [[STRUCT_ZOT]] %tmp, 0, 0
+; CHECK-NEXT:    [[TMP1:%.*]] = extractvalue [[STRUCT_ZOT]] undef, 0, 0
 ; CHECK-NEXT:    ret void
 ;
 bb:
   %tmp = call %struct.zot @widget(<8 x i32> %arg)
   %tmp1 = extractvalue %struct.zot %tmp, 0, 0
   ret void
 }

llvm/test/Transforms/IPConstantProp/arg-count-mismatch.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -S -o - | FileCheck %s
+; RUN: opt < %s -ipsccp -S -o - | FileCheck %s
 
 ; The original C source looked like this:
 ;
 ;   long long a101, b101, e101;
 ;   volatile long c101;
 ;   int d101;
 ;
 ;   static inline int bar(p1, p2)

 
 ;-------------------------------------------------------------------------------
 ; Additional tests to verify that we still optimize when having a mismatch
 ; in argument count due to varargs (as long as all non-variadic arguments have
 ; been provided),
 
 define internal i16 @vararg_prop(i16 %p1, ...) {
 ; CHECK-LABEL: @vararg_prop(
-; CHECK-NEXT:    ret i16 7
+; CHECK-NEXT:    ret i16 undef
 ;
   ret i16 %p1
 }
 
 define dso_local i16 @vararg_tests(i16 %a) {
 ; CHECK-LABEL: @vararg_tests(
 ; CHECK-NEXT:    [[CALL1:%.*]] = call i16 (i16, ...) @vararg_prop(i16 7, i16 8, i16 [[A:%.*]])
 ; CHECK-NEXT:    [[CALL2:%.*]] = call i16 bitcast (i16 (i16, i16, ...)* @vararg_no_prop to i16 (i16)*)(i16 7)

llvm/test/Transforms/IPConstantProp/arg-type-mismatch.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -S -o - | FileCheck %s
+; RUN: opt < %s -ipsccp -S -o - | FileCheck %s
 
 ; This test is just to verify that we do not crash/assert due to mismatch in
 ; argument type between the caller and callee.
 
 define dso_local void @foo(i16 %a) {
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:    [[CALL:%.*]] = call i16 bitcast (i16 (i16, i16)* @bar to i16 (i16, i32)*)(i16 [[A:%.*]], i32 7)
 ; CHECK-NEXT:    ret void

llvm/test/Transforms/IPConstantProp/comdat-ipo.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -S | FileCheck %s
+; RUN: opt < %s -ipsccp -S | FileCheck %s
 
 ; See PR26774
 
 define i32 @baz() {
 ; CHECK-LABEL: @baz(
 ; CHECK-NEXT:    ret i32 10
 ;
   ret i32 10

llvm/test/Transforms/IPConstantProp/deadarg.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -disable-output
+; RUN: opt < %s -ipsccp -disable-output
 define internal void @foo(i32 %X) {
   call void @foo( i32 %X )
   ret void
 }
 

llvm/test/Transforms/IPConstantProp/multiple_callbacks.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -ipconstprop -S < %s | FileCheck %s
+;
 ;
 ;                            /---------------------------------------|
 ;                            |                /----------------------|----|
 ;                            |                |                /-----|    |
 ;                            V                V                V     |    |
 ;    void broker(int (*cb0)(int), int (*cb1)(int), int (*cb2)(int), int, int);
 ;
 ;    static int cb0(int zero) {

llvm/test/Transforms/IPConstantProp/naked-return.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
 ; RUN: opt -ipsccp -S %s | FileCheck %s
-; RUN: opt -ipconstprop -S %s | FileCheck %s
 
 target datalayout = "e-m:x-p:32:32-i64:64-f80:32-n8:16:32-a:0:32-S32"
 target triple = "i686-pc-windows-msvc19.0.24215"
 
 define i32 @dipsy(i32, i32) local_unnamed_addr #0 {
 ; CHECK-LABEL: @dipsy(
 ; CHECK-NEXT:  BasicBlock0:
 ; CHECK-NEXT:    call void asm "\0D\0Apushl %ebp\0D\0Amovl 8(%esp),%eax\0D\0Amovl 12(%esp), %ebp\0D\0Acalll *%eax\0D\0Apopl %ebp\0D\0Aretl\0D\0A", ""()

llvm/test/Transforms/IPConstantProp/openmp_parallel_for.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -S -ipconstprop < %s | FileCheck %s
+; RUN: opt -S -ipsccp < %s | FileCheck %s
 ;
 ;    void bar(int, float, double);
 ;
 ;    void foo(int N) {
 ;      float p = 3;
 ;      double q = 5;
 ;      N = 7;
 ;

 define internal void @.omp_outlined.(i32* noalias %.global_tid., i32* noalias %.bound_tid., i32* dereferenceable(4) %N, float* dereferenceable(4) %p, i64 %q) {
 ; CHECK-LABEL: @.omp_outlined.(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[Q_ADDR:%.*]] = alloca i64, align 8
 ; CHECK-NEXT:    [[DOTOMP_LB:%.*]] = alloca i32, align 4
 ; CHECK-NEXT:    [[DOTOMP_UB:%.*]] = alloca i32, align 4
 ; CHECK-NEXT:    [[DOTOMP_STRIDE:%.*]] = alloca i32, align 4
 ; CHECK-NEXT:    [[DOTOMP_IS_LAST:%.*]] = alloca i32, align 4
-; CHECK-NEXT:    store i64 4617315517961601024, i64* [[Q_ADDR]], align 8
+; CHECK-NEXT:    store i64 [[Q:%.*]], i64* [[Q_ADDR]], align 8
 ; CHECK-NEXT:    [[CONV:%.*]] = bitcast i64* [[Q_ADDR]] to double*
 ; CHECK-NEXT:    [[TMP:%.*]] = load i32, i32* [[N:%.*]], align 4
 ; CHECK-NEXT:    [[SUB3:%.*]] = add nsw i32 [[TMP]], -3
 ; CHECK-NEXT:    [[CMP:%.*]] = icmp sgt i32 [[TMP]], 2
 ; CHECK-NEXT:    br i1 [[CMP]], label [[OMP_PRECOND_THEN:%.*]], label [[OMP_PRECOND_END:%.*]]
 ; CHECK:       omp.precond.then:
 ; CHECK-NEXT:    store i32 0, i32* [[DOTOMP_LB]], align 4
 ; CHECK-NEXT:    store i32 [[SUB3]], i32* [[DOTOMP_UB]], align 4

llvm/test/Transforms/IPConstantProp/pthreads.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -ipconstprop -S < %s | FileCheck %s
+; RUN: opt -ipsccp -S < %s | FileCheck %s
 ;
 ;    #include <pthread.h>
 ;
 ;    void *GlobalVPtr;
 ;
 ;    static void *foo(void *arg) { return arg; }
 ;    static void *bar(void *arg) { return arg; }
 ;
entry:
   ret i32 0
 }
 
 declare !callback !0 dso_local i32 @pthread_create(i64*, %union.pthread_attr_t*, i8* (i8*)*, i8*)
 
 define internal i8* @foo(i8* %arg) {
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    ret i8* null
+; CHECK-NEXT:    ret i8* [[ARG:%.*]]
 ;
 entry:
   ret i8* %arg
 }
 
 define internal i8* @bar(i8* %arg) {
 ; CHECK-LABEL: @bar(
 ; CHECK-NEXT:  entry:
-; CHECK-NEXT:    ret i8* bitcast (i8** @GlobalVPtr to i8*)
+; CHECK-NEXT:    ret i8* [[ARG:%.*]]
 ;
 entry:
   ret i8* %arg
 }
 
 !1 = !{i64 2, i64 3, i1 false}
 !0 = !{!1}

llvm/test/Transforms/IPConstantProp/recursion.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -deadargelim -S | FileCheck %s
+; RUN: opt < %s -ipsccp -deadargelim -S | FileCheck %s
 
 ; CHECK-NOT: %X
 
 define internal i32 @foo(i32 %X) {
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:    [[Y:%.*]] = call i32 @foo()
 ; CHECK-NEXT:    [[Z:%.*]] = add i32 [[Y]], 1
 ; CHECK-NEXT:    ret i32 [[Z]]

llvm/test/Transforms/IPConstantProp/return-argument.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -S | FileCheck %s
+; RUN: opt < %s -ipsccp -S | FileCheck %s
 
 ;; This function returns its second argument on all return statements
 define internal i32* @incdec(i1 %C, i32* %V) {
 ; CHECK-LABEL: @incdec(
 ; CHECK-NEXT:    [[X:%.*]] = load i32, i32* [[V:%.*]], align 4
 ; CHECK-NEXT:    br i1 [[C:%.*]], label [[T:%.*]], label [[F:%.*]]
 ; CHECK:       T:
 ; CHECK-NEXT:    [[X1:%.*]] = add i32 [[X]], 1
;
   ret { i32, i32 } %Z
 }
 
 define void @caller(i1 %C) personality i32 (...)* @__gxx_personality_v0 {
 ; CHECK-LABEL: @caller(
 ; CHECK-NEXT:    [[Q:%.*]] = alloca i32, align 4
 ; CHECK-NEXT:    [[W:%.*]] = call i32* @incdec(i1 [[C:%.*]], i32* [[Q]])
 ; CHECK-NEXT:    [[S1:%.*]] = call { i32, i32 } @foo(i32 1, i32 2)
+; CHECK-NEXT:    [[X1:%.*]] = extractvalue { i32, i32 } [[S1]], 0
 ; CHECK-NEXT:    [[S2:%.*]] = invoke { i32, i32 } @foo(i32 3, i32 4)
 ; CHECK-NEXT:    to label [[OK:%.*]] unwind label [[LPAD:%.*]]
 ; CHECK:       OK:
-; CHECK-NEXT:    [[Z:%.*]] = add i32 1, 3
-; CHECK-NEXT:    store i32 [[Z]], i32* [[Q]], align 4
+; CHECK-NEXT:    [[X2:%.*]] = extractvalue { i32, i32 } [[S2]], 0
+; CHECK-NEXT:    [[Z:%.*]] = add i32 [[X1]], [[X2]]
+; CHECK-NEXT:    store i32 [[Z]], i32* [[W]], align 4
 ; CHECK-NEXT:    br label [[RET:%.*]]
 ; CHECK:       LPAD:
 ; CHECK-NEXT:    [[EXN:%.*]] = landingpad { i8*, i32 }
 ; CHECK-NEXT:    cleanup
 ; CHECK-NEXT:    br label [[RET]]
 ; CHECK:       RET:
 ; CHECK-NEXT:    ret void
 ;

llvm/test/Transforms/IPConstantProp/return-constant.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -instcombine -S | FileCheck %s
+; RUN: opt < %s -ipsccp -instcombine -S | FileCheck %s
 
 define internal i32 @foo(i1 %C) {
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:    br i1 [[C:%.*]], label [[T:%.*]], label [[F:%.*]]
 ; CHECK:       T:
-; CHECK-NEXT:    ret i32 52
+; CHECK-NEXT:    ret i32 undef
 ; CHECK:       F:
-; CHECK-NEXT:    ret i32 52
+; CHECK-NEXT:    ret i32 undef
 ;
   br i1 %C, label %T, label %F
 
 T:              ; preds = %0
   ret i32 52
 
 F:              ; preds = %0
   ret i32 52

llvm/test/Transforms/IPConstantProp/return-constants.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -ipconstprop -S | FileCheck %s
+; RUN: opt < %s -ipsccp -S | FileCheck %s
 
 %0 = type { i32, i32 }
 
 define internal %0 @foo(i1 %Q) {
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:    br i1 [[Q:%.*]], label [[T:%.*]], label [[F:%.*]]
 ; CHECK:       T:
-; CHECK-NEXT:    [[MRV:%.*]] = insertvalue [[TMP0:%.*]] undef, i32 21, 0
-; CHECK-NEXT:    [[MRV1:%.*]] = insertvalue [[TMP0]] %mrv, i32 22, 1
-; CHECK-NEXT:    ret [[TMP0]] %mrv1
+; CHECK-NEXT:    ret [[TMP0:%.*]] { i32 21, i32 22 }
 ; CHECK:       F:
-; CHECK-NEXT:    [[MRV2:%.*]] = insertvalue [[TMP0]] undef, i32 21, 0
-; CHECK-NEXT:    [[MRV3:%.*]] = insertvalue [[TMP0]] %mrv2, i32 23, 1
-; CHECK-NEXT:    ret [[TMP0]] %mrv3
+; CHECK-NEXT:    ret [[TMP0]] { i32 21, i32 23 }
 ;
   br i1 %Q, label %T, label %F
 
 T:                                                ; preds = %0
   %mrv = insertvalue %0 undef, i32 21, 0
   %mrv1 = insertvalue %0 %mrv, i32 22, 1
   ret %0 %mrv1
 
 F:                                                ; preds = %0
   %mrv2 = insertvalue %0 undef, i32 21, 0
   %mrv3 = insertvalue %0 %mrv2, i32 23, 1
   ret %0 %mrv3
 }
 
 define internal %0 @bar(i1 %Q) {
 ; CHECK-LABEL: @bar(
-; CHECK-NEXT:    [[A:%.*]] = insertvalue [[TMP0:%.*]] undef, i32 21, 0
 ; CHECK-NEXT:    br i1 [[Q:%.*]], label [[T:%.*]], label [[F:%.*]]
 ; CHECK:       T:
-; CHECK-NEXT:    [[B:%.*]] = insertvalue [[TMP0]] %A, i32 22, 1
-; CHECK-NEXT:    ret [[TMP0]] %B
+; CHECK-NEXT:    ret [[TMP0:%.*]] { i32 21, i32 22 }
 ; CHECK:       F:
-; CHECK-NEXT:    [[C:%.*]] = insertvalue [[TMP0]] %A, i32 23, 1
-; CHECK-NEXT:    ret [[TMP0]] %C
+; CHECK-NEXT:    ret [[TMP0]] { i32 21, i32 23 }
 ;
   %A = insertvalue %0 undef, i32 21, 0
   br i1 %Q, label %T, label %F
 
 T:                                                ; preds = %0
   %B = insertvalue %0 %A, i32 22, 1
   ret %0 %B
 
 F:                                                ; preds = %0
   %C = insertvalue %0 %A, i32 23, 1
   ret %0 %C
 }
 
 define %0 @caller(i1 %Q) {
 ; CHECK-LABEL: @caller(
 ; CHECK-NEXT:    [[X:%.*]] = call [[TMP0:%.*]] @foo(i1 [[Q:%.*]])
 ; CHECK-NEXT:    [[B:%.*]] = extractvalue [[TMP0]] %X, 1
 ; CHECK-NEXT:    [[Y:%.*]] = call [[TMP0]] @bar(i1 [[Q]])
 ; CHECK-NEXT:    [[D:%.*]] = extractvalue [[TMP0]] %Y, 1
-; CHECK-NEXT:    [[M:%.*]] = add i32 21, 21
 ; CHECK-NEXT:    [[N:%.*]] = add i32 [[B]], [[D]]
 ; CHECK-NEXT:    ret [[TMP0]] %X
 ;
   %X = call %0 @foo(i1 %Q)
   %A = extractvalue %0 %X, 0
   %B = extractvalue %0 %X, 1
   %Y = call %0 @bar(i1 %Q)
   %C = extractvalue %0 %Y, 0
   %D = extractvalue %0 %Y, 1
   %M = add i32 %A, %C
   %N = add i32 %B, %D
   ret %0 %X
 }

llvm/test/Transforms/IPConstantProp/thread_local_acs.ll

 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -ipconstprop -S < %s | FileCheck %s
+; RUN: opt -ipsccp -S < %s | FileCheck %s
 ;
 ;    #include <threads.h>
 ;    thread_local int gtl = 0;
 ;    int gsh = 0;
 ;
 ;    static int callee(int *thread_local_ptr, int *shared_ptr) {
 ;      return *thread_local_ptr + *shared_ptr;
 ;    }
 ;
 ;    void broker(int *, int (*callee)(int *, int *), int *);
 ;
 ;    void caller() {
 ;      broker(&gtl, callee, &gsh);
 ;    }
 ;
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
 @gtl = dso_local thread_local global i32 0, align 4
 @gsh = dso_local global i32 0, align 4
 
 define internal i32 @callee(i32* %thread_local_ptr, i32* %shared_ptr) {
 ; CHECK-LABEL: @callee(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    [[TMP:%.*]] = load i32, i32* [[THREAD_LOCAL_PTR:%.*]], align 4
-; CHECK-NEXT:    [[TMP1:%.*]] = load i32, i32* @gsh, align 4
+; CHECK-NEXT:    [[TMP1:%.*]] = load i32, i32* [[SHARED_PTR:%.*]], align 4
 ; CHECK-NEXT:    [[ADD:%.*]] = add nsw i32 [[TMP]], [[TMP1]]
 ; CHECK-NEXT:    ret i32 [[ADD]]
 ;
 entry:
   %tmp = load i32, i32* %thread_local_ptr, align 4
   %tmp1 = load i32, i32* %shared_ptr, align 4
   %add = add nsw i32 %tmp, %tmp1
   ret i32 %add

llvm/utils/findoptdiff

 ll2="${bc2}.ll"
 opt1ll="${bc1}.opt.ll"
 opt2ll="${bc2}.opt.ll"
 dis1="$llvm1/Debug/bin/llvm-dis"
 dis2="$llvm2/Debug/bin/llvm-dis"
 opt1="$llvm1/Debug/bin/opt"
 opt2="$llvm2/Debug/bin/opt"
 
-all_switches="-verify -lowersetjmp -simplifycfg -mem2reg -globalopt -globaldce -ipconstprop -deadargelim -instcombine -simplifycfg -prune-eh -inline -simplify-libcalls -argpromotion -tailduplicate -simplifycfg -sroa -instcombine -predsimplify -condprop -tailcallelim -simplifycfg -reassociate -licm -loop-unswitch -instcombine -indvars -loop-unroll -instcombine -load-vn -gcse -sccp -instcombine -condprop -dse -dce -simplifycfg -deadtypeelim -constmerge -internalize -ipsccp -globalopt -constmerge -deadargelim -inline -prune-eh -globalopt -globaldce -argpromotion -instcombine -predsimplify -sroa -globalsmodref-aa -licm -load-vn -gcse -dse -instcombine -simplifycfg -verify"
+all_switches="-verify -lowersetjmp -simplifycfg -mem2reg -globalopt -globaldce -deadargelim -instcombine -simplifycfg -prune-eh -inline -simplify-libcalls -argpromotion -tailduplicate -simplifycfg -sroa -instcombine -predsimplify -condprop -tailcallelim -simplifycfg -reassociate -licm -loop-unswitch -instcombine -indvars -loop-unroll -instcombine -load-vn -gcse -sccp -instcombine -condprop -dse -dce -simplifycfg -deadtypeelim -constmerge -internalize -ipsccp -globalopt -constmerge -deadargelim -inline -prune-eh -globalopt -globaldce -argpromotion -instcombine -predsimplify -sroa -globalsmodref-aa -licm -load-vn -gcse -dse -instcombine -simplifycfg -verify"
 
 #counter=0
 function tryit {
   switches_to_use="$1"
   $opt1 $switches_to_use "$bc1" -o - | $dis1 | $filt1 > "$opt1ll"
   $opt2 $switches_to_use "$bc2" -o - | $dis2 | $filt2 > "$opt2ll"
   diffs="diffs."$((counter++))
   diff "$opt1ll" "$opt2ll" > $diffs

llvm/utils/gn/secondary/llvm/lib/Transforms/IPO/BUILD.gn

sources = [
     "ExtractGV.cpp",
     "ForceFunctionAttrs.cpp",
     "FunctionAttrs.cpp",
     "FunctionImport.cpp",
     "GlobalDCE.cpp",
     "GlobalOpt.cpp",
     "GlobalSplit.cpp",
     "HotColdSplitting.cpp",
-    "IPConstantPropagation.cpp",
     "IPO.cpp",
     "InferFunctionAttrs.cpp",
     "InlineSimple.cpp",
     "Inliner.cpp",
     "Internalize.cpp",
     "LoopExtractor.cpp",
     "LowerTypeTests.cpp",
     "MergeFunctions.cpp",