From 016c6b2104ec98fa186f5d46d3c29bfd9791feff Mon Sep 17 00:00:00 2001 From: Reid Kleckner Date: Wed, 11 Mar 2015 23:36:10 +0000 Subject: [PATCH] Handle big index in getelementptr instruction MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit CodeGen incorrectly ignores (assert from APInt) constant index bigger than 2^64 in getelementptr instruction. This is a test and fix for that. Patch by Paweł Bylica! Reviewed By: rnk Subscribers: majnemer, rnk, mcrosier, resistor, llvm-commits Differential Revision: http://reviews.llvm.org/D8219 llvm-svn: 231984 --- llvm/lib/CodeGen/SelectionDAG/FastISel.cpp | 6 +- .../CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 27 +++----- llvm/test/CodeGen/X86/getelementptr.ll | 80 ++++++++++++++++++++++ 3 files changed, 92 insertions(+), 21 deletions(-) create mode 100644 llvm/test/CodeGen/X86/getelementptr.ll diff --git a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp index faa36b0..16724b0 100644 --- a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp @@ -497,7 +497,7 @@ bool FastISel::selectGetElementPtr(const User *I) { OI != E; ++OI) { const Value *Idx = *OI; if (auto *StTy = dyn_cast(Ty)) { - unsigned Field = cast(Idx)->getZExtValue(); + uint64_t Field = cast(Idx)->getZExtValue(); if (Field) { // N = N + Offset TotalOffs += DL.getStructLayout(StTy)->getElementOffset(Field); @@ -518,8 +518,8 @@ bool FastISel::selectGetElementPtr(const User *I) { if (CI->isZero()) continue; // N = N + Offset - TotalOffs += - DL.getTypeAllocSize(Ty) * cast(CI)->getSExtValue(); + uint64_t IdxN = CI->getValue().sextOrTrunc(64).getSExtValue(); + TotalOffs += DL.getTypeAllocSize(Ty) * IdxN; if (TotalOffs >= MaxOffs) { N = fastEmit_ri_(VT, ISD::ADD, N, NIsKill, TotalOffs, VT); if (!N) // Unhandled operand. Halt "fast" selection and bail. diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index 6fc6eb1..5a58273 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -3448,30 +3448,21 @@ void SelectionDAGBuilder::visitGetElementPtr(const User &I) { Ty = StTy->getElementType(Field); } else { Ty = cast(Ty)->getElementType(); + MVT PtrTy = DAG.getTargetLoweringInfo().getPointerTy(AS); + unsigned PtrSize = PtrTy.getSizeInBits(); + APInt ElementSize(PtrSize, DL->getTypeAllocSize(Ty)); // If this is a constant subscript, handle it quickly. - const TargetLowering &TLI = DAG.getTargetLoweringInfo(); - if (const ConstantInt *CI = dyn_cast(Idx)) { - if (CI->isZero()) continue; - uint64_t Offs = - DL->getTypeAllocSize(Ty)*cast(CI)->getSExtValue(); - SDValue OffsVal; - EVT PTy = TLI.getPointerTy(AS); - unsigned PtrBits = PTy.getSizeInBits(); - if (PtrBits < 64) - OffsVal = DAG.getNode(ISD::TRUNCATE, getCurSDLoc(), PTy, - DAG.getConstant(Offs, MVT::i64)); - else - OffsVal = DAG.getConstant(Offs, PTy); - - N = DAG.getNode(ISD::ADD, getCurSDLoc(), N.getValueType(), N, - OffsVal); + if (const auto *CI = dyn_cast(Idx)) { + if (CI->isZero()) + continue; + APInt Offs = ElementSize * CI->getValue().sextOrTrunc(PtrSize); + SDValue OffsVal = DAG.getConstant(Offs, PtrTy); + N = DAG.getNode(ISD::ADD, getCurSDLoc(), N.getValueType(), N, OffsVal); continue; } // N = N + Idx * ElementSize; - APInt ElementSize = - APInt(TLI.getPointerSizeInBits(AS), DL->getTypeAllocSize(Ty)); SDValue IdxN = getValue(Idx); // If the index is smaller or larger than intptr_t, truncate or extend diff --git a/llvm/test/CodeGen/X86/getelementptr.ll b/llvm/test/CodeGen/X86/getelementptr.ll new file mode 100644 index 0000000..e260e7d --- /dev/null +++ b/llvm/test/CodeGen/X86/getelementptr.ll @@ -0,0 +1,80 @@ +; RUN: llc < %s -O0 -march=x86 +; RUN: llc < %s -O0 -march=x86-64 +; RUN: llc < %s -O2 -march=x86 +; RUN: llc < %s -O2 -march=x86-64 + + +; Test big index trunc to pointer size: + +define i8* @test_trunc65(i8* %ptr) nounwind { +; CHECK-LABEL: test_trunc65 +; CHECK: 3 + %d = getelementptr i8, i8* %ptr, i65 18446744073709551619 ; 2^64 + 3 + ret i8* %d +} + +define i8* @test_trunc128(i8* %ptr) nounwind { +; CHECK-LABEL: test_trunc128 +; CHECK: 5 + %d = getelementptr i8, i8* %ptr, i128 18446744073709551621 ; 2^64 + 5 + ret i8* %d +} + +define i8* @test_trunc160(i8* %ptr) nounwind { +; CHECK-LABEL: test_trunc160 +; CHECK: 8 + %d = getelementptr i8, i8* %ptr, i160 18446744073709551624 ; 2^64 + 8 + ret i8* %d +} + +define i8* @test_trunc256(i8* %ptr) nounwind { +; CHECK-LABEL: test_trunc256 +; CHECK: 13 + %d = getelementptr i8, i8* %ptr, i256 18446744073709551629 ; 2^64 + 13 + ret i8* %d +} + +define i8* @test_trunc2048(i8* %ptr) nounwind { +; CHECK-LABEL: test_trunc2048 +; CHECK: 21 + %d = getelementptr i8, i8* %ptr, i2048 18446744073709551637 ; 2^64 + 21 + ret i8* %d +} + + +; Test small index sext to pointer size + +define i8* @test_sext3(i8* %ptr) nounwind { +; CHECK-LABEL: test_sext3 +; CHECK: -3 + %d = getelementptr i8, i8* %ptr, i3 -3 + ret i8* %d +} + +define i8* @test_sext5(i8* %ptr) nounwind { +; CHECK-LABEL: test_sext5 +; CHECK: -5 + %d = getelementptr i8, i8* %ptr, i5 -5 + ret i8* %d +} + +define i8* @test_sext8(i8* %ptr) nounwind { +; CHECK-LABEL: test_sext8 +; CHECK: -8 + %d = getelementptr i8, i8* %ptr, i8 -8 + ret i8* %d +} + +define i8* @test_sext13(i8* %ptr) nounwind { +; CHECK-LABEL: test_sext13 +; CHECK: -13 + %d = getelementptr i8, i8* %ptr, i8 -13 + ret i8* %d +} + +define i8* @test_sext16(i8* %ptr) nounwind { +; CHECK-LABEL: test_sext16 +; CHECK: -21 + %d = getelementptr i8, i8* %ptr, i8 -21 + ret i8* %d +} -- 2.7.4