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-rw-r--r--llvm/lib/Transforms/Scalar/SCCP.cpp100
-rw-r--r--llvm/test/Transforms/SCCP/ip-constan-ranges.ll135
2 files changed, 7 insertions, 228 deletions
diff --git a/llvm/lib/Transforms/Scalar/SCCP.cpp b/llvm/lib/Transforms/Scalar/SCCP.cpp
index 087bb0250fe..067af7f2cd3 100644
--- a/llvm/lib/Transforms/Scalar/SCCP.cpp
+++ b/llvm/lib/Transforms/Scalar/SCCP.cpp
@@ -30,7 +30,6 @@
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Analysis/GlobalsModRef.h"
#include "llvm/Analysis/TargetLibraryInfo.h"
-#include "llvm/Analysis/ValueLattice.h"
#include "llvm/Analysis/ValueLatticeUtils.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CallSite.h"
@@ -71,8 +70,6 @@ STATISTIC(NumDeadBlocks , "Number of basic blocks unreachable");
STATISTIC(IPNumInstRemoved, "Number of instructions removed by IPSCCP");
STATISTIC(IPNumArgsElimed ,"Number of arguments constant propagated by IPSCCP");
STATISTIC(IPNumGlobalConst, "Number of globals found to be constant by IPSCCP");
-STATISTIC(IPNumRangeInfoUsed, "Number of times constant range info was used by"
- "IPSCCP");
namespace {
@@ -177,14 +174,6 @@ public:
Val.setInt(forcedconstant);
Val.setPointer(V);
}
-
- ValueLatticeElement toValueLattice() const {
- if (isOverdefined())
- return ValueLatticeElement::getOverdefined();
- if (isConstant())
- return ValueLatticeElement::get(getConstant());
- return ValueLatticeElement();
- }
};
//===----------------------------------------------------------------------===//
@@ -197,8 +186,6 @@ class SCCPSolver : public InstVisitor<SCCPSolver> {
const TargetLibraryInfo *TLI;
SmallPtrSet<BasicBlock *, 8> BBExecutable; // The BBs that are executable.
DenseMap<Value *, LatticeVal> ValueState; // The state each value is in.
- // The state each parameter is in.
- DenseMap<Value *, ValueLatticeElement> ParamState;
/// StructValueState - This maintains ValueState for values that have
/// StructType, for example for formal arguments, calls, insertelement, etc.
@@ -325,18 +312,10 @@ public:
return StructValues;
}
- ValueLatticeElement getLatticeValueFor(Value *V) {
- std::pair<DenseMap<Value*, ValueLatticeElement>::iterator, bool>
- PI = ParamState.insert(std::make_pair(V, ValueLatticeElement()));
- ValueLatticeElement &LV = PI.first->second;
- if (PI.second) {
- DenseMap<Value*, LatticeVal>::const_iterator I = ValueState.find(V);
- assert(I != ValueState.end() &&
- "V not found in ValueState nor Paramstate map!");
- LV = I->second.toValueLattice();
- }
-
- return LV;
+ LatticeVal getLatticeValueFor(Value *V) const {
+ DenseMap<Value*, LatticeVal>::const_iterator I = ValueState.find(V);
+ assert(I != ValueState.end() && "V is not in valuemap!");
+ return I->second;
}
/// getTrackedRetVals - Get the inferred return value map.
@@ -465,18 +444,6 @@ private:
return LV;
}
- ValueLatticeElement &getParamState(Value *V) {
- assert(!V->getType()->isStructTy() && "Should use getStructValueState");
-
- std::pair<DenseMap<Value*, ValueLatticeElement>::iterator, bool>
- PI = ParamState.insert(std::make_pair(V, ValueLatticeElement()));
- ValueLatticeElement &LV = PI.first->second;
- if (PI.second)
- LV = getValueState(V).toValueLattice();
-
- return LV;
- }
-
/// getStructValueState - Return the LatticeVal object that corresponds to the
/// value/field pair. This function handles the case when the value hasn't
/// been seen yet by properly seeding constants etc.
@@ -1203,9 +1170,6 @@ CallOverdefined:
mergeInValue(getStructValueState(&*AI, i), &*AI, CallArg);
}
} else {
- // Most other parts of the Solver still only use the simpler value
- // lattice, so we propagate changes for parameters to both lattices.
- getParamState(&*AI).mergeIn(getValueState(*CAI).toValueLattice(), DL);
mergeInValue(&*AI, getValueState(*CAI));
}
}
@@ -1596,43 +1560,6 @@ bool SCCPSolver::ResolvedUndefsIn(Function &F) {
return false;
}
-static bool tryToReplaceWithConstantRange(SCCPSolver &Solver, Value *V) {
- bool Changed = false;
-
- const ValueLatticeElement &IV = Solver.getLatticeValueFor(V);
- if (IV.isOverdefined())
- return false;
-
- // Currently we only use range information for integer values.
- if (!(V->getType()->isIntegerTy() && IV.isConstantRange()))
- return false;
-
- for (auto UI = V->uses().begin(), E = V->uses().end(); UI != E;) {
- const Use &U = *UI++;
- auto *Icmp = dyn_cast<ICmpInst>(U.getUser());
- if (!Icmp || !Solver.isBlockExecutable(Icmp->getParent()))
- continue;
-
- auto A = Solver.getLatticeValueFor(Icmp->getOperand(0));
- auto B = Solver.getLatticeValueFor(Icmp->getOperand(1));
- Constant *C = nullptr;
- if (A.satisfiesPredicate(Icmp->getPredicate(), B))
- C = ConstantInt::getTrue(Icmp->getType());
- else if (A.satisfiesPredicate(Icmp->getInversePredicate(), B))
- C = ConstantInt::getFalse(Icmp->getType());
-
- if (C) {
- Icmp->replaceAllUsesWith(C);
- DEBUG(dbgs() << "Replacing " << *Icmp << " with " << *C
- << ", because of range information " << A << " " << B
- << "\n");
- Icmp->eraseFromParent();
- Changed = true;
- }
- }
- return Changed;
-}
-
static bool tryToReplaceWithConstant(SCCPSolver &Solver, Value *V) {
Constant *Const = nullptr;
if (V->getType()->isStructTy()) {
@@ -1650,19 +1577,10 @@ static bool tryToReplaceWithConstant(SCCPSolver &Solver, Value *V) {
}
Const = ConstantStruct::get(ST, ConstVals);
} else {
- const ValueLatticeElement &IV = Solver.getLatticeValueFor(V);
+ LatticeVal IV = Solver.getLatticeValueFor(V);
if (IV.isOverdefined())
return false;
-
- if (IV.isConstantRange()) {
- if (IV.getConstantRange().isSingleElement())
- Const =
- ConstantInt::get(V->getType(), IV.asConstantInteger().getValue());
- else
- return false;
- } else
- Const =
- IV.isConstant() ? IV.getConstant() : UndefValue::get(V->getType());
+ Const = IV.isConstant() ? IV.getConstant() : UndefValue::get(V->getType());
}
assert(Const && "Constant is nullptr here!");
DEBUG(dbgs() << " Constant: " << *Const << " = " << *V << '\n');
@@ -1863,14 +1781,10 @@ static bool runIPSCCP(Module &M, const DataLayout &DL,
if (Solver.isBlockExecutable(&F.front()))
for (Function::arg_iterator AI = F.arg_begin(), E = F.arg_end(); AI != E;
- ++AI) {
+ ++AI)
if (!AI->use_empty() && tryToReplaceWithConstant(Solver, &*AI))
++IPNumArgsElimed;
- if (!AI->use_empty() && tryToReplaceWithConstantRange(Solver, &*AI))
- ++IPNumRangeInfoUsed;
- }
-
for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB) {
if (!Solver.isBlockExecutable(&*BB)) {
DEBUG(dbgs() << " BasicBlock Dead:" << *BB);
diff --git a/llvm/test/Transforms/SCCP/ip-constan-ranges.ll b/llvm/test/Transforms/SCCP/ip-constan-ranges.ll
deleted file mode 100644
index 4f5f63e5f73..00000000000
--- a/llvm/test/Transforms/SCCP/ip-constan-ranges.ll
+++ /dev/null
@@ -1,135 +0,0 @@
-; RUN: opt < %s -ipsccp -S | FileCheck %s
-
-; Constant range for %a is [1, 48) and for %b is [301, 1000)
-; CHECK-LABEL: f1
-; CHECK-NOT: icmp
-; CHECK: %a.1 = select i1 false, i32 1, i32 2
-; CHECK: %b.1 = select i1 true, i32 1, i32 2
-; CHECK: %a.2 = select i1 false, i32 1, i32 2
-; CHECK: %b.2 = select i1 true, i32 1, i32 2
-define internal i32 @f1(i32 %a, i32 %b) {
-entry:
- %cmp.a = icmp sgt i32 %a, 300
- %cmp.b = icmp sgt i32 %b, 300
- %cmp.a2 = icmp ugt i32 %a, 300
- %cmp.b2 = icmp ugt i32 %b, 300
-
- %a.1 = select i1 %cmp.a, i32 1, i32 2
- %b.1 = select i1 %cmp.b, i32 1, i32 2
- %a.2 = select i1 %cmp.a2, i32 1, i32 2
- %b.2 = select i1 %cmp.b2, i32 1, i32 2
- %res1 = add i32 %a.1, %b.1
- %res2 = add i32 %a.2, %b.2
- %res3 = add i32 %res1, %res2
- ret i32 %res3
-}
-
-; Constant range for %x is [47, 302)
-; CHECK-LABEL: f2
-; CHECK: %cmp = icmp sgt i32 %x, 300
-; CHECK: %res1 = select i1 %cmp, i32 1, i32 2
-; CHECK-NEXT: %res2 = select i1 true, i32 3, i32 4
-; CHECK-NEXT: %res3 = select i1 true, i32 5, i32 6
-; CHECK-NEXT: %res4 = select i1 %cmp4, i32 3, i32 4
-; CHECK-NEXT: %res5 = select i1 true, i32 5, i32 6
-define internal i32 @f2(i32 %x) {
-entry:
- %cmp = icmp sgt i32 %x, 300
- %cmp2 = icmp ne i32 %x, 10
- %cmp3 = icmp sge i32 %x, 47
- %cmp4 = icmp ugt i32 %x, 300
- %cmp5 = icmp uge i32 %x, 47
- %res1 = select i1 %cmp, i32 1, i32 2
- %res2 = select i1 %cmp2, i32 3, i32 4
- %res3 = select i1 %cmp3, i32 5, i32 6
- %res4 = select i1 %cmp4, i32 3, i32 4
- %res5 = select i1 %cmp5, i32 5, i32 6
-
- %res6 = add i32 %res1, %res2
- %res7 = add i32 %res3, %res4
- %res = add i32 %res6, %res5
- ret i32 %res
-}
-
-define i32 @caller1() {
-entry:
- %call1 = tail call i32 @f1(i32 1, i32 301)
- %call2 = tail call i32 @f1(i32 47, i32 999)
- %call3 = tail call i32 @f2(i32 47)
- %call4 = tail call i32 @f2(i32 301)
- %res = add nsw i32 %call1, %call2
- %res.1 = add nsw i32 %res, %call3
- %res.2 = add nsw i32 %res.1, %call4
- ret i32 %res.2
-}
-
-; x is overdefined, because constant ranges are only used for parameter
-; values.
-; CHECK-LABEL: f3
-; CHECK: %cmp = icmp sgt i32 %x, 300
-; CHECK: %res = select i1 %cmp, i32 1, i32 2
-; CHECK: ret i32 %res
-define internal i32 @f3(i32 %x) {
-entry:
- %cmp = icmp sgt i32 %x, 300
- %res = select i1 %cmp, i32 1, i32 2
- ret i32 %res
-}
-
-; The phi node could be converted in a ConstantRange.
-define i32 @caller2(i1 %cmp) {
-entry:
- br i1 %cmp, label %if.true, label %end
-
-if.true:
- br label %end
-
-end:
- %res = phi i32 [ 0, %entry], [ 1, %if.true ]
- %call1 = tail call i32 @f3(i32 %res)
- ret i32 %call1
-}
-
-; CHECK-LABEL: f4
-; CHECK: %cmp = icmp sgt i32 %x, 300
-; CHECK: %res = select i1 %cmp, i32 1, i32 2
-; CHECK: ret i32 %res
-define internal i32 @f4(i32 %x) {
-entry:
- %cmp = icmp sgt i32 %x, 300
- %res = select i1 %cmp, i32 1, i32 2
- ret i32 %res
-}
-
-; ICmp could introduce bounds on ConstantRanges.
-define i32 @caller3(i32 %x) {
-entry:
- %cmp = icmp sgt i32 %x, 300
- br i1 %cmp, label %if.true, label %end
-
-if.true:
- %x.1 = tail call i32 @f4(i32 %x)
- br label %end
-
-end:
- %res = phi i32 [ 0, %entry], [ %x.1, %if.true ]
- ret i32 %res
-}
-
-; Check to make sure we do not attempt to access lattice values in unreachable
-; blocks.
-define i32 @test_unreachable() {
-entry:
- call i1 @test_unreachable_callee(i32 1)
- call i1 @test_unreachable_callee(i32 2)
- ret i32 1
-}
-
-define internal i1 @test_unreachable_callee(i32 %a) {
-entry:
- ret i1 true
-
-unreachablebb:
- %cmp = icmp eq i32 undef, %a
- unreachable
-}
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