forked from OSchip/llvm-project
[SCEV] Do not apply info from loop guards in AddRecs.
We cannot guarantee that the replacement expression is loop-invariant in all AddRecs in the source expression. Use a rewriter that skips AddRecExpr for now. Fixes PR47776.
This commit is contained in:
Florian Hahn
parent
9e796d5e71
commit
8f56e382f7
|
|
@ -12705,6 +12705,27 @@ const SCEV* ScalarEvolution::computeMaxBackedgeTakenCount(const Loop *L) {
|
|||
return getUMinFromMismatchedTypes(ExitCounts);
|
||||
}
|
||||
|
||||
/// This rewriter is similar to SCEVParameterRewriter (it replaces SCEVUnknown
|
||||
/// components following the Map (Value -> SCEV)), but skips AddRecExpr because
|
||||
/// we cannot guarantee that the replacement is loop invariant in the loop of
|
||||
/// the AddRec.
|
||||
class SCEVLoopGuardRewriter : public SCEVRewriteVisitor<SCEVLoopGuardRewriter> {
|
||||
ValueToSCEVMapTy ⤅
|
||||
|
||||
public:
|
||||
SCEVLoopGuardRewriter(ScalarEvolution &SE, ValueToSCEVMapTy &M)
|
||||
: SCEVRewriteVisitor(SE), Map(M) {}
|
||||
|
||||
const SCEV *visitAddRecExpr(const SCEVAddRecExpr *Expr) { return Expr; }
|
||||
|
||||
const SCEV *visitUnknown(const SCEVUnknown *Expr) {
|
||||
auto I = Map.find(Expr->getValue());
|
||||
if (I == Map.end())
|
||||
return Expr;
|
||||
return I->second;
|
||||
}
|
||||
};
|
||||
|
||||
const SCEV *ScalarEvolution::applyLoopGuards(const SCEV *Expr, const Loop *L) {
|
||||
auto CollectCondition = [&](ICmpInst::Predicate Predicate, const SCEV *LHS,
|
||||
const SCEV *RHS, ValueToSCEVMapTy &RewriteMap) {
|
||||
|
|
@ -12787,5 +12808,6 @@ const SCEV *ScalarEvolution::applyLoopGuards(const SCEV *Expr, const Loop *L) {
|
|||
|
||||
if (RewriteMap.empty())
|
||||
return Expr;
|
||||
return SCEVParameterRewriter::rewrite(Expr, *this, RewriteMap);
|
||||
SCEVLoopGuardRewriter Rewriter(*this, RewriteMap);
|
||||
return Rewriter.visit(Expr);
|
||||
}
|
||||
|
|
|
|||
|
|
@ -0,0 +1,112 @@
|
|||
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
|
||||
; RUN: opt -loop-reduce -S %s | FileCheck %s
|
||||
|
||||
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128-ni:1-p2:32:8:8:32-ni:2"
|
||||
target triple = "x86_64-unknown-linux-gnu"
|
||||
|
||||
; Make sure we do not crash when applying info from loop guards to expressions in @bar.
|
||||
; Test case for PR47776.
|
||||
|
||||
define void @bar() personality i32* ()* @zot {
|
||||
; CHECK-LABEL: @bar(
|
||||
; CHECK-NEXT: bb:
|
||||
; CHECK-NEXT: br label [[BB1:%.*]]
|
||||
; CHECK: bb1.loopexit:
|
||||
; CHECK-NEXT: br label [[BB1]]
|
||||
; CHECK: bb1:
|
||||
; CHECK-NEXT: [[TMP:%.*]] = phi i32 [ 1, [[BB:%.*]] ], [ 0, [[BB1_LOOPEXIT:%.*]] ]
|
||||
; CHECK-NEXT: br label [[BB2:%.*]]
|
||||
; CHECK: bb2:
|
||||
; CHECK-NEXT: [[TMP3:%.*]] = phi i64 [ 0, [[BB1]] ], [ [[TMP7:%.*]], [[BB5:%.*]] ]
|
||||
; CHECK-NEXT: [[TMP4:%.*]] = invoke i32 @fn()
|
||||
; CHECK-NEXT: to label [[BB5]] unwind label [[BB23_LOOPEXIT_SPLIT_LP:%.*]]
|
||||
; CHECK: bb5:
|
||||
; CHECK-NEXT: [[TMP6:%.*]] = load atomic i32, i32 addrspace(1)* undef unordered, align 8
|
||||
; CHECK-NEXT: [[TMP7]] = add nuw nsw i64 [[TMP3]], 1
|
||||
; CHECK-NEXT: [[C_0:%.*]] = icmp ult i64 [[TMP7]], 10000
|
||||
; CHECK-NEXT: br i1 [[C_0]], label [[BB2]], label [[BB8:%.*]]
|
||||
; CHECK: bb8:
|
||||
; CHECK-NEXT: [[TMP9:%.*]] = icmp ult i32 [[TMP]], [[TMP6]]
|
||||
; CHECK-NEXT: br i1 [[TMP9]], label [[BB10:%.*]], label [[BB29:%.*]]
|
||||
; CHECK: bb10:
|
||||
; CHECK-NEXT: [[TMP11:%.*]] = mul i32 [[TMP]], -1
|
||||
; CHECK-NEXT: [[TMP0:%.*]] = sext i32 [[TMP11]] to i64
|
||||
; CHECK-NEXT: [[TMP1:%.*]] = add nsw i64 [[TMP0]], 1
|
||||
; CHECK-NEXT: [[TMP2:%.*]] = sub i64 [[TMP1]], [[TMP7]]
|
||||
; CHECK-NEXT: [[TMP1:%.*]] = trunc i64 [[TMP2]] to i32
|
||||
; CHECK-NEXT: [[TMP16:%.*]] = and i32 [[TMP1]], 7
|
||||
; CHECK-NEXT: br label [[BB17:%.*]]
|
||||
; CHECK: bb17:
|
||||
; CHECK-NEXT: [[TMP18:%.*]] = phi i32 [ [[TMP21:%.*]], [[BB20:%.*]] ], [ [[TMP16]], [[BB10]] ]
|
||||
; CHECK-NEXT: [[TMP19:%.*]] = invoke i32 @fn()
|
||||
; CHECK-NEXT: to label [[BB20]] unwind label [[BB23_LOOPEXIT:%.*]]
|
||||
; CHECK: bb20:
|
||||
; CHECK-NEXT: [[TMP21]] = add i32 [[TMP18]], -1
|
||||
; CHECK-NEXT: [[TMP22:%.*]] = icmp eq i32 [[TMP21]], 0
|
||||
; CHECK-NEXT: br i1 [[TMP22]], label [[BB1_LOOPEXIT]], label [[BB17]]
|
||||
; CHECK: bb23.loopexit:
|
||||
; CHECK-NEXT: [[LPAD_LOOPEXIT:%.*]] = landingpad token
|
||||
; CHECK-NEXT: cleanup
|
||||
; CHECK-NEXT: br label [[BB23:%.*]]
|
||||
; CHECK: bb23.loopexit.split-lp:
|
||||
; CHECK-NEXT: [[LPAD_LOOPEXIT_SPLIT_LP:%.*]] = landingpad token
|
||||
; CHECK-NEXT: cleanup
|
||||
; CHECK-NEXT: br label [[BB23]]
|
||||
; CHECK: bb23:
|
||||
; CHECK-NEXT: ret void
|
||||
; CHECK: bb29:
|
||||
; CHECK-NEXT: ret void
|
||||
;
|
||||
bb:
|
||||
br label %bb1
|
||||
|
||||
bb1: ; preds = %bb20, %bb
|
||||
%tmp = phi i32 [ 1, %bb ], [ 0, %bb20 ]
|
||||
br label %bb2
|
||||
|
||||
bb2: ; preds = %bb5, %bb1
|
||||
%tmp3 = phi i64 [ 0, %bb1 ], [ %tmp7, %bb5 ]
|
||||
%tmp4 = invoke i32 @fn()
|
||||
to label %bb5 unwind label %bb23
|
||||
|
||||
bb5: ; preds = %bb2
|
||||
%tmp6 = load atomic i32, i32 addrspace(1)* undef unordered, align 8
|
||||
%tmp7 = add nuw nsw i64 %tmp3, 1
|
||||
%c.0 = icmp ult i64 %tmp7, 10000
|
||||
br i1 %c.0, label %bb2, label %bb8
|
||||
|
||||
bb8: ; preds = %bb5
|
||||
%tmp9 = icmp ult i32 %tmp, %tmp6
|
||||
br i1 %tmp9, label %bb10, label %bb29
|
||||
|
||||
bb10: ; preds = %bb8
|
||||
%tmp11 = mul i32 %tmp, -1
|
||||
%tmp12 = zext i32 %tmp11 to i64
|
||||
%tmp13 = sub i64 %tmp12, %tmp7
|
||||
%tmp14 = add i64 %tmp13, 1
|
||||
%tmp15 = trunc i64 %tmp14 to i32
|
||||
%tmp16 = and i32 %tmp15, 7
|
||||
br label %bb17
|
||||
|
||||
bb17: ; preds = %bb20, %bb10
|
||||
%tmp18 = phi i32 [ %tmp21, %bb20 ], [ %tmp16, %bb10 ]
|
||||
%tmp19 = invoke i32 @fn()
|
||||
to label %bb20 unwind label %bb23
|
||||
|
||||
bb20: ; preds = %bb17
|
||||
%tmp21 = add i32 %tmp18, -1
|
||||
%tmp22 = icmp eq i32 %tmp21, 0
|
||||
br i1 %tmp22, label %bb1, label %bb17
|
||||
|
||||
bb23: ; preds = %bb17
|
||||
%tmp24 = landingpad token
|
||||
cleanup
|
||||
ret void
|
||||
|
||||
bb29: ; preds = %bb8
|
||||
ret void
|
||||
}
|
||||
|
||||
declare i32* @zot() #1
|
||||
|
||||
declare i32 @fn()
|
||||
Loading…
Reference in New Issue