diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp index 4365adc629f..23f75630b76 100644 --- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -2027,9 +2027,10 @@ ICmpInst *LoopStrengthReduce::ChangeCompareStride(Loop *L, ICmpInst *Cond, Scale = SSInt / CmpSSInt; int64_t NewCmpVal = CmpVal * Scale; - APInt Mul = APInt(BitWidth, NewCmpVal); + APInt Mul = APInt(BitWidth*2, CmpVal); + Mul = Mul * APInt(BitWidth*2, Scale); // Check for overflow. - if (Mul.getSExtValue() != NewCmpVal) + if (!Mul.isSignedIntN(BitWidth)) continue; // Watch out for overflow. diff --git a/test/Transforms/LoopStrengthReduce/2009-05-04-Overflow.ll b/test/Transforms/LoopStrengthReduce/2009-05-04-Overflow.ll new file mode 100644 index 00000000000..28a78ec3ba8 --- /dev/null +++ b/test/Transforms/LoopStrengthReduce/2009-05-04-Overflow.ll @@ -0,0 +1,122 @@ +; Check that we do not strength reduce to an overflowiong loop condition +; RUN: llvm-as < %s | opt -loop-reduce | llvm-dis | not grep 4755160694556239428 + +target datalayout = "e-p:64:64" +target triple = "x86_64-unknown-linux-gnu" +@"initialized$$$CFE_id_3d9e38d5_main" = linkonce global [3 x i64] [i64 6729544817907097974, i64 754394135718280480, i64 0] +@"initialized$main$$CFE_id_3d9e38d5_main" = linkonce global [512 x i64] zeroinitializer + +define i32 @main() { +"file loop.c, line 10, bb14": + %vals = alloca [512 x i64], align 16 + br label %"file loop.c, line 10, bb101" + +"file loop.c, line 10, bb101": + br label %"file loop.c, line 10, in inner vector loop at depth 0, bb62" + +"file loop.c, line 10, in inner vector loop at depth 0, bb62": + %"$SI_S13.0" = phi i64 [ 0, %"file loop.c, line 10, bb101" ], [ %r35, %"file loop.c, line 13, in inner vector loop at depth 0, bb63" ] + %"$LC_S14.0" = phi i64 [ -256, %"file loop.c, line 10, bb101" ], [ %r37, %"file loop.c, line 13, in inner vector loop at depth 0, bb63" ] + br label %"file loop.c, line 13, in inner vector loop at depth 0, bb63" + +"file loop.c, line 13, in inner vector loop at depth 0, bb63": + %r3 = add i64 %"$SI_S13.0", ptrtoint ([512 x i64]* @"initialized$main$$CFE_id_3d9e38d5_main" to i64) + %vals18 = bitcast [512 x i64]* %vals to i8* + %ctg2 = getelementptr i8* %vals18, i64 %"$SI_S13.0" + %r9 = inttoptr i64 %r3 to <2 x i64>* + %r10 = load <2 x i64>* %r9, align 8 + %r12 = bitcast i8* %ctg2 to <2 x i64>* + store <2 x i64> %r10, <2 x i64>* %r12, align 16 + %tmp17 = inttoptr i64 %r3 to <2 x i64>* + %r15 = getelementptr <2 x i64>* %tmp17, i64 1 + %r16 = load <2 x i64>* %r15, align 8 + %ctg2.sum19 = or i64 %"$SI_S13.0", 16 + %r19 = getelementptr i8* %vals18, i64 %ctg2.sum19 + %0 = bitcast i8* %r19 to <2 x i64>* + store <2 x i64> %r16, <2 x i64>* %0, align 16 + %tmp15 = inttoptr i64 %r3 to <2 x i64>* + %r22 = getelementptr <2 x i64>* %tmp15, i64 2 + %r23 = load <2 x i64>* %r22, align 8 + %ctg2.sum20 = or i64 %"$SI_S13.0", 32 + %r26 = getelementptr i8* %vals18, i64 %ctg2.sum20 + %1 = bitcast i8* %r26 to <2 x i64>* + store <2 x i64> %r23, <2 x i64>* %1, align 16 + %tmp13 = inttoptr i64 %r3 to <2 x i64>* + %r29 = getelementptr <2 x i64>* %tmp13, i64 3 + %r30 = load <2 x i64>* %r29, align 8 + %ctg2.sum21 = or i64 %"$SI_S13.0", 48 + %r33 = getelementptr i8* %vals18, i64 %ctg2.sum21 + %2 = bitcast i8* %r33 to <2 x i64>* + store <2 x i64> %r30, <2 x i64>* %2, align 16 + %r35 = add i64 %"$SI_S13.0", 64 + %r37 = add i64 %"$LC_S14.0", 4 + %r39 = icmp slt i64 %r37, 0 + br i1 %r39, label %"file loop.c, line 10, in inner vector loop at depth 0, bb62", label %"file loop.c, line 15, bb51" + +"file loop.c, line 15, bb51": + %3 = getelementptr [512 x i64]* %vals, i64 0, i64 0 + store i64 0, i64* %3, align 16 + br label %"file loop.c, line 10, in inner loop at depth 0, bb65" + +"file loop.c, line 10, in inner loop at depth 0, bb65": + %"$vals_WR0_S15.0" = phi i64 [ 0, %"file loop.c, line 15, bb51" ], [ %r70, %"file loop.c, line 16, in inner loop at depth 0, bb67" ] + %"$i_S16.0" = phi i64 [ 0, %"file loop.c, line 15, bb51" ], [ %r78, %"file loop.c, line 16, in inner loop at depth 0, bb67" ] + br label %"file loop.c, line 16, in inner loop at depth 0, bb67" + +"file loop.c, line 16, in inner loop at depth 0, bb67": + %r45 = add i64 %"$vals_WR0_S15.0", 81985529216486895 + %r5111 = or i64 %"$i_S16.0", 1 + %r5212 = getelementptr [512 x i64]* %vals, i64 0, i64 %r5111 + store i64 %r45, i64* %r5212, align 8 + %r54 = add i64 %"$vals_WR0_S15.0", 163971058432973790 + %r599 = or i64 %"$i_S16.0", 2 + %r6010 = getelementptr [512 x i64]* %vals, i64 0, i64 %r599 + store i64 %r54, i64* %r6010, align 16 + %r62 = add i64 %"$vals_WR0_S15.0", 245956587649460685 + %r677 = or i64 %"$i_S16.0", 3 + %r688 = getelementptr [512 x i64]* %vals, i64 0, i64 %r677 + store i64 %r62, i64* %r688, align 8 + %r70 = add i64 %"$vals_WR0_S15.0", 327942116865947580 + %r75 = add i64 %"$i_S16.0", 4 + %r766 = getelementptr [512 x i64]* %vals, i64 0, i64 %r75 + store i64 %r70, i64* %r766, align 16 + %r78 = add i64 %"$i_S16.0", 4 + %r80 = icmp slt i64 %r78, 508 + br i1 %r80, label %"file loop.c, line 10, in inner loop at depth 0, bb65", label %"file loop.c, line 16, bb39" + +"file loop.c, line 16, bb39": + %r84 = add i64 %"$vals_WR0_S15.0", 409927646082434475 + %r885 = getelementptr [512 x i64]* %vals, i64 0, i64 509 + store i64 %r84, i64* %r885, align 8 + %r90 = add i64 %"$vals_WR0_S15.0", 491913175298921370 + %r944 = getelementptr [512 x i64]* %vals, i64 0, i64 510 + store i64 %r90, i64* %r944, align 16 + %r1003 = getelementptr [512 x i64]* %vals, i64 0, i64 511 + %r96.c = add i64 %"$vals_WR0_S15.0", 573898704515408265 + store i64 %r96.c, i64* %r1003, align 8 + br label %"file loop.c, line 10, in inner loop at depth 0, bb13" + +"file loop.c, line 10, in inner loop at depth 0, bb13": + %"$i_S17.0" = phi i64 [ 0, %"file loop.c, line 16, bb39" ], [ %r111, %"file loop.c, line 19, in inner loop at depth 0, bb25" ] + br label %"file loop.c, line 19, in inner loop at depth 0, bb6" + +"file loop.c, line 19, in inner loop at depth 0, bb6": + %r102 = add i64 %"$i_S17.0", 1 + %r106 = add i64 %"$i_S17.0", 1 + %r1071 = getelementptr [512 x i64]* %vals, i64 0, i64 %r106 + %r1072 = load i64* %r1071, align 8 + %r109 = call i32 (...)* @printf([17 x i8]* bitcast ([3 x i64]* @"initialized$$$CFE_id_3d9e38d5_main" to [17 x i8]*), i64 %r102, i64 %r1072) + br label %"file loop.c, line 19, in inner loop at depth 0, bb25" + +"file loop.c, line 19, in inner loop at depth 0, bb25": + %r111 = add i64 %"$i_S17.0", 1 + %r113 = icmp slt i64 %r111, 511 + br i1 %r113, label %"file loop.c, line 10, in inner loop at depth 0, bb13", label %"file loop.c, line 19, bb10" + +"file loop.c, line 19, bb10": + ret i32 0 +} + +declare i8* @llvm.returnaddress(i32) nounwind readnone + +declare i32 @printf(...)