[llvm] 257eda0 - [NFC][LVI] getPredicateAt(): drop default value for UseBlockValue

[Roman Lebedev via llvm-commits]

Author: Roman Lebedev
Date: 2021-04-10T20:46:01+03:00
New Revision: 257eda07940d8e6d46dbb5944589a0186e07c6e9

URL: https://github.com/llvm/llvm-project/commit/257eda07940d8e6d46dbb5944589a0186e07c6e9
DIFF: https://github.com/llvm/llvm-project/commit/257eda07940d8e6d46dbb5944589a0186e07c6e9.diff

LOG: [NFC][LVI] getPredicateAt(): drop default value for UseBlockValue

The default is likely wrong.
Out of all the callees, only a single one needs to pass-in false (JumpThread),
everything else either already passes true, or should pass true.

Until the default is flipped, at least make it harder to unintentionally
add new callees with UseBlockValue=false.

Added: 
    

Modified: 
    llvm/include/llvm/Analysis/LazyValueInfo.h
    llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
    llvm/lib/Transforms/Scalar/JumpThreading.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Analysis/LazyValueInfo.h b/llvm/include/llvm/Analysis/LazyValueInfo.h
index 363cb49af382..d5a407352284 100644
--- a/llvm/include/llvm/Analysis/LazyValueInfo.h
+++ b/llvm/include/llvm/Analysis/LazyValueInfo.h
@@ -75,7 +75,7 @@ class LazyValueInfo {
   /// \p Pred is a CmpInst predicate. If \p UseBlockValue is true, the block
   /// value is also taken into account.
   Tristate getPredicateAt(unsigned Pred, Value *V, Constant *C,
-                          Instruction *CxtI, bool UseBlockValue = false);
+                          Instruction *CxtI, bool UseBlockValue);
 
   /// Determine whether the specified value is known to be a constant at the
   /// specified instruction. Return null if not.

diff  --git a/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp b/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
index e84f6eb63da5..9a62f2f6641a 100644
--- a/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
+++ b/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
@@ -597,8 +597,8 @@ static bool processCallSite(CallBase &CB, LazyValueInfo *LVI) {
     if (Type && !CB.paramHasAttr(ArgNo, Attribute::NonNull) &&
         !isa<Constant>(V) &&
         LVI->getPredicateAt(ICmpInst::ICMP_EQ, V,
-                            ConstantPointerNull::get(Type),
-                            &CB) == LazyValueInfo::False)
+                            ConstantPointerNull::get(Type), &CB,
+                            /*UseBlockValue=*/false) == LazyValueInfo::False)
       ArgNos.push_back(ArgNo);
     ArgNo++;
   }
@@ -619,13 +619,15 @@ static bool processCallSite(CallBase &CB, LazyValueInfo *LVI) {
 
 static bool isNonNegative(Value *V, LazyValueInfo *LVI, Instruction *CxtI) {
   Constant *Zero = ConstantInt::get(V->getType(), 0);
-  auto Result = LVI->getPredicateAt(ICmpInst::ICMP_SGE, V, Zero, CxtI);
+  auto Result = LVI->getPredicateAt(ICmpInst::ICMP_SGE, V, Zero, CxtI,
+                                    /*UseBlockValue=*/false);
   return Result == LazyValueInfo::True;
 }
 
 static bool isNonPositive(Value *V, LazyValueInfo *LVI, Instruction *CxtI) {
   Constant *Zero = ConstantInt::get(V->getType(), 0);
-  auto Result = LVI->getPredicateAt(ICmpInst::ICMP_SLE, V, Zero, CxtI);
+  auto Result = LVI->getPredicateAt(ICmpInst::ICMP_SLE, V, Zero, CxtI,
+                                    /*UseBlockValue=*/false);
   return Result == LazyValueInfo::True;
 }
 
@@ -975,8 +977,8 @@ static Constant *getConstantAt(Value *V, Instruction *At, LazyValueInfo *LVI) {
   Constant *Op1 = dyn_cast<Constant>(C->getOperand(1));
   if (!Op1) return nullptr;
 
-  LazyValueInfo::Tristate Result =
-    LVI->getPredicateAt(C->getPredicate(), Op0, Op1, At);
+  LazyValueInfo::Tristate Result = LVI->getPredicateAt(
+      C->getPredicate(), Op0, Op1, At, /*UseBlockValue=*/false);
   if (Result == LazyValueInfo::Unknown)
     return nullptr;
 

diff  --git a/llvm/lib/Transforms/Scalar/JumpThreading.cpp b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
index e4852958703a..92b33f08e6fc 100644
--- a/llvm/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
@@ -1155,8 +1155,8 @@ bool JumpThreadingPass::processBlock(BasicBlock *BB) {
       assert(CondBr->isConditional() && "Threading on unconditional terminator");
 
       LazyValueInfo::Tristate Ret =
-        LVI->getPredicateAt(CondCmp->getPredicate(), CondCmp->getOperand(0),
-                            CondConst, CondBr);
+          LVI->getPredicateAt(CondCmp->getPredicate(), CondCmp->getOperand(0),
+                              CondConst, CondBr, /*UseBlockValue=*/false);
       if (Ret != LazyValueInfo::Unknown) {
         unsigned ToRemove = Ret == LazyValueInfo::True ? 1 : 0;
         unsigned ToKeep = Ret == LazyValueInfo::True ? 0 : 1;