BranchInst *Branch;
RangeCheckKind Kind;
- static RangeCheckKind parseRangeCheckICmp(ICmpInst *ICI, ScalarEvolution &SE,
- Value *&Index, Value *&Length);
+ static RangeCheckKind parseRangeCheckICmp(Loop *L, ICmpInst *ICI,
+ ScalarEvolution &SE, Value *&Index,
+ Value *&Length);
static InductiveRangeCheck::RangeCheckKind
parseRangeCheck(Loop *L, ScalarEvolution &SE, Value *Condition,
/// RANGE_CHECK_UPPER.
///
InductiveRangeCheck::RangeCheckKind
-InductiveRangeCheck::parseRangeCheckICmp(ICmpInst *ICI, ScalarEvolution &SE,
- Value *&Index, Value *&Length) {
+InductiveRangeCheck::parseRangeCheckICmp(Loop *L, ICmpInst *ICI,
+ ScalarEvolution &SE, Value *&Index,
+ Value *&Length) {
+
+ auto IsNonNegativeAndNotLoopVarying = [&SE, L](Value *V) {
+ const SCEV *S = SE.getSCEV(V);
+ if (isa<SCEVCouldNotCompute>(S))
+ return false;
+
+ return SE.getLoopDisposition(S, L) == ScalarEvolution::LoopInvariant &&
+ SE.isKnownNonNegative(S);
+ };
using namespace llvm::PatternMatch;
return RANGE_CHECK_LOWER;
}
- if (SE.isKnownNonNegative(SE.getSCEV(LHS))) {
+ if (IsNonNegativeAndNotLoopVarying(LHS)) {
Index = RHS;
Length = LHS;
return RANGE_CHECK_UPPER;
std::swap(LHS, RHS);
// fallthrough
case ICmpInst::ICMP_UGT:
- if (SE.isKnownNonNegative(SE.getSCEV(LHS))) {
+ if (IsNonNegativeAndNotLoopVarying(LHS)) {
Index = RHS;
Length = LHS;
return RANGE_CHECK_BOTH;
if (!ICmpA || !ICmpB)
return InductiveRangeCheck::RANGE_CHECK_UNKNOWN;
- auto RCKindA = parseRangeCheckICmp(ICmpA, SE, IndexA, LengthA);
- auto RCKindB = parseRangeCheckICmp(ICmpB, SE, IndexB, LengthB);
+ auto RCKindA = parseRangeCheckICmp(L, ICmpA, SE, IndexA, LengthA);
+ auto RCKindB = parseRangeCheckICmp(L, ICmpB, SE, IndexB, LengthB);
if (RCKindA == InductiveRangeCheck::RANGE_CHECK_UNKNOWN ||
RCKindB == InductiveRangeCheck::RANGE_CHECK_UNKNOWN)
if (ICmpInst *ICI = dyn_cast<ICmpInst>(Condition)) {
Value *IndexVal = nullptr;
- auto RCKind = parseRangeCheckICmp(ICI, SE, IndexVal, Length);
+ auto RCKind = parseRangeCheckICmp(L, ICI, SE, IndexVal, Length);
if (RCKind == InductiveRangeCheck::RANGE_CHECK_UNKNOWN)
return InductiveRangeCheck::RANGE_CHECK_UNKNOWN;
--- /dev/null
+; RUN: opt -irce-print-changed-loops -S -irce -verify < %s 2>&1 | FileCheck %s
+
+; CHECK-NOT: constrained loop
+
+define void @single_access_no_preloop_no_offset(i32 *%arr, i32 *%a_len_ptr, i32 %n) {
+ entry:
+ %first.itr.check = icmp sgt i32 %n, 0
+ br i1 %first.itr.check, label %loop, label %exit
+
+ loop:
+ %idx = phi i32 [ 0, %entry ] , [ %idx.next, %in.bounds ]
+ %idx.next = add i32 %idx, 1
+ %len = load i32, i32* %a_len_ptr, !range !0
+ %abc = icmp slt i32 %idx, %len
+ br i1 %abc, label %in.bounds, label %out.of.bounds, !prof !1
+
+ in.bounds:
+ %addr = getelementptr i32, i32* %arr, i32 %idx
+ store i32 0, i32* %addr
+ %next = icmp slt i32 %idx.next, %n
+ br i1 %next, label %loop, label %exit
+
+ out.of.bounds:
+ ret void
+
+ exit:
+ ret void
+}
+
+!0 = !{i32 0, i32 2147483647}
+!1 = !{!"branch_weights", i32 64, i32 4}