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[SCEV] Collect guard info for ICMP NE w/o constants. #160500

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[SCEV] Collect guard info for ICMP NE w/o constants. #160500

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10 changes: 10 additions & 0 deletions llvm/lib/Analysis/ScalarEvolution.cpp
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Expand Up @@ -15873,6 +15873,16 @@ void ScalarEvolution::LoopGuards::collectFromBlock(
const SCEV *OneAlignedUp =
DividesBy ? GetNextSCEVDividesByDivisor(One, DividesBy) : One;
To = SE.getUMaxExpr(FromRewritten, OneAlignedUp);
} else {
if (LHS->getType()->isPointerTy()) {
LHS = SE.getLosslessPtrToIntExpr(LHS);
RHS = SE.getLosslessPtrToIntExpr(RHS);
if (isa<SCEVCouldNotCompute>(LHS) || isa<SCEVCouldNotCompute>(RHS))
break;
}
From = SE.getMinusSCEV(RHS, LHS);
FromRewritten = From;
To = SE.getUMaxExpr(FromRewritten, SE.getOne(From->getType()));
}
break;
default:
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10 changes: 5 additions & 5 deletions llvm/test/Analysis/ScalarEvolution/ptrtoint.ll
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Expand Up @@ -382,7 +382,7 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
; X64-NEXT: %i9 = ptrtoint ptr %i7 to i64
; X64-NEXT: --> {(ptrtoint ptr %arg to i64),+,1}<nuw><%bb6> U: full-set S: full-set Exits: (-1 + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
; X64-NEXT: %i10 = sub i64 %i9, %i4
; X64-NEXT: --> {0,+,1}<nuw><%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
; X64-NEXT: --> {0,+,1}<nuw><%bb6> U: [0,-1) S: [0,-1) Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64)) LoopDispositions: { %bb6: Computable }
; X64-NEXT: %i11 = getelementptr inbounds i8, ptr %arg2, i64 %i10
; X64-NEXT: --> {%arg2,+,1}<nw><%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64) + %arg2) LoopDispositions: { %bb6: Computable }
; X64-NEXT: %i12 = load i8, ptr %i11, align 1
Expand All @@ -393,7 +393,7 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
; X64-NEXT: --> {(1 + %arg),+,1}<nuw><%bb6> U: full-set S: full-set Exits: ((-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64) + %arg) LoopDispositions: { %bb6: Computable }
; X64-NEXT: Determining loop execution counts for: @pr46786_c26_char
; X64-NEXT: Loop %bb6: backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64))
; X64-NEXT: Loop %bb6: constant max backedge-taken count is i64 -1
; X64-NEXT: Loop %bb6: constant max backedge-taken count is i64 -2
; X64-NEXT: Loop %bb6: symbolic max backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i64)) + (ptrtoint ptr %arg1 to i64))
; X64-NEXT: Loop %bb6: Trip multiple is 1
;
Expand All @@ -406,9 +406,9 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
; X32-NEXT: %i8 = load i8, ptr %i7, align 1
; X32-NEXT: --> %i8 U: full-set S: full-set Exits: <<Unknown>> LoopDispositions: { %bb6: Variant }
; X32-NEXT: %i9 = ptrtoint ptr %i7 to i64
; X32-NEXT: --> {(zext i32 (ptrtoint ptr %arg to i32) to i64),+,1}<nuw><%bb6> U: [0,8589934591) S: [0,8589934591) Exits: ((zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) + (zext i32 (ptrtoint ptr %arg to i32) to i64)) LoopDispositions: { %bb6: Computable }
; X32-NEXT: --> {(zext i32 (ptrtoint ptr %arg to i32) to i64),+,1}<nuw><%bb6> U: [0,8589934590) S: [0,8589934590) Exits: ((zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) + (zext i32 (ptrtoint ptr %arg to i32) to i64)) LoopDispositions: { %bb6: Computable }
; X32-NEXT: %i10 = sub i64 %i9, %i4
; X32-NEXT: --> {0,+,1}<nuw><%bb6> U: [0,4294967296) S: [0,4294967296) Exits: (zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) LoopDispositions: { %bb6: Computable }
; X32-NEXT: --> {0,+,1}<nuw><%bb6> U: [0,4294967295) S: [0,4294967295) Exits: (zext i32 (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32)) to i64) LoopDispositions: { %bb6: Computable }
; X32-NEXT: %i11 = getelementptr inbounds i8, ptr %arg2, i64 %i10
; X32-NEXT: --> {%arg2,+,1}<%bb6> U: full-set S: full-set Exits: (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32) + %arg2) LoopDispositions: { %bb6: Computable }
; X32-NEXT: %i12 = load i8, ptr %i11, align 1
Expand All @@ -419,7 +419,7 @@ define void @pr46786_c26_char(ptr %arg, ptr %arg1, ptr %arg2) {
; X32-NEXT: --> {(1 + %arg),+,1}<nuw><%bb6> U: full-set S: full-set Exits: ((-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32) + %arg) LoopDispositions: { %bb6: Computable }
; X32-NEXT: Determining loop execution counts for: @pr46786_c26_char
; X32-NEXT: Loop %bb6: backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32))
; X32-NEXT: Loop %bb6: constant max backedge-taken count is i32 -1
; X32-NEXT: Loop %bb6: constant max backedge-taken count is i32 -2
; X32-NEXT: Loop %bb6: symbolic max backedge-taken count is (-1 + (-1 * (ptrtoint ptr %arg to i32)) + (ptrtoint ptr %arg1 to i32))
; X32-NEXT: Loop %bb6: Trip multiple is 1
;
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2 changes: 1 addition & 1 deletion llvm/test/Transforms/IndVarSimplify/pointer-loop-guards.ll
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Expand Up @@ -18,7 +18,7 @@ define i64 @test_ptr_compare_guard(ptr %start, ptr %end) {
; CHECK-NEXT: br i1 [[C_1]], label %[[LOOP_LATCH]], label %[[EXIT_LOOPEXIT:.*]]
; CHECK: [[LOOP_LATCH]]:
; CHECK-NEXT: [[PTR_IV_NEXT]] = getelementptr i8, ptr [[PTR_IV]], i64 1
; CHECK-NEXT: [[I64_IV_NEXT]] = add i64 [[I64_IV]], 1
; CHECK-NEXT: [[I64_IV_NEXT]] = add nuw i64 [[I64_IV]], 1
; CHECK-NEXT: [[C_2:%.*]] = icmp eq ptr [[PTR_IV_NEXT]], [[END]]
; CHECK-NEXT: br i1 [[C_2]], label %[[EXIT_LOOPEXIT]], label %[[LOOP_HEADER]]
; CHECK: [[EXIT_LOOPEXIT]]:
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3 changes: 1 addition & 2 deletions llvm/test/Transforms/LoopUnroll/scevunroll.ll
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Expand Up @@ -465,8 +465,7 @@ define void @peel_int_eq_condition(i32 %start) {
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[IV:%.*]] = phi i32 [ [[IV_NEXT_PEEL]], [[ENTRY_PEEL_NEWPH]] ], [ [[IV_NEXT:%.*]], [[LOOP_LATCH:%.*]] ]
; CHECK-NEXT: [[C_0:%.*]] = icmp eq i32 [[IV]], [[START]]
; CHECK-NEXT: br i1 [[C_0]], label [[IF_THEN:%.*]], label [[LOOP_LATCH]]
; CHECK-NEXT: br i1 false, label [[IF_THEN:%.*]], label [[LOOP_LATCH]]
; CHECK: if.then:
; CHECK-NEXT: call void @fn(i32 [[IV]])
; CHECK-NEXT: br label [[LOOP_LATCH]]
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