diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index b07f3814d9d2d..20dcb0e0be878 100644 --- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -14903,12 +14903,29 @@ SDValue DAGCombiner::reduceLoadWidth(SDNode *N) { AddToWorklist(NewPtr.getNode()); SDValue Load; - if (ExtType == ISD::NON_EXTLOAD) - Load = DAG.getLoad(VT, DL, LN0->getChain(), NewPtr, - LN0->getPointerInfo().getWithOffset(PtrOff), - LN0->getOriginalAlign(), - LN0->getMemOperand()->getFlags(), LN0->getAAInfo()); - else + if (ExtType == ISD::NON_EXTLOAD) { + const MDNode *OldRanges = LN0->getRanges(); + const MDNode *NewRanges = nullptr; + // If LSBs are loaded and the truncated ConstantRange for the OldRanges + // metadata is not the full-set for the NewWidth then create a NewRanges + // metadata for the truncated load + if (ShAmt == 0 && OldRanges) { + ConstantRange CR = getConstantRangeFromMetadata(*OldRanges); + ConstantRange TruncatedCR = CR.truncate(VT.getScalarSizeInBits()); + + if (!TruncatedCR.isFullSet()) { + Metadata *Bounds[2] = {ConstantAsMetadata::get(ConstantInt::get( + *DAG.getContext(), TruncatedCR.getLower())), + ConstantAsMetadata::get(ConstantInt::get( + *DAG.getContext(), TruncatedCR.getUpper()))}; + NewRanges = MDNode::get(*DAG.getContext(), Bounds); + } + } + Load = DAG.getLoad( + VT, DL, LN0->getChain(), NewPtr, + LN0->getPointerInfo().getWithOffset(PtrOff), LN0->getOriginalAlign(), + LN0->getMemOperand()->getFlags(), LN0->getAAInfo(), NewRanges); + } else Load = DAG.getExtLoad(ExtType, DL, VT, LN0->getChain(), NewPtr, LN0->getPointerInfo().getWithOffset(PtrOff), ExtVT, LN0->getOriginalAlign(), diff --git a/llvm/test/CodeGen/AMDGPU/shl64_reduce.ll b/llvm/test/CodeGen/AMDGPU/shl64_reduce.ll index 05430213c17d2..69242f4e44840 100644 --- a/llvm/test/CodeGen/AMDGPU/shl64_reduce.ll +++ b/llvm/test/CodeGen/AMDGPU/shl64_reduce.ll @@ -13,23 +13,66 @@ ; Test range with metadata ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; -; FIXME: This case should be reduced, but SelectionDAG::computeKnownBits() cannot -; determine the minimum from metadata in this case. Match current results -; for now. - define i64 @shl_metadata(i64 %arg0, ptr %arg1.ptr) { ; CHECK-LABEL: shl_metadata: ; CHECK: ; %bb.0: ; CHECK-NEXT: s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0) +; CHECK-NEXT: flat_load_dword v1, v[2:3] +; CHECK-NEXT: s_waitcnt vmcnt(0) lgkmcnt(0) +; CHECK-NEXT: v_lshlrev_b32_e32 v1, v1, v0 +; CHECK-NEXT: v_mov_b32_e32 v0, 0 +; CHECK-NEXT: s_setpc_b64 s[30:31] + %shift.amt = load i64, ptr %arg1.ptr, !range !0, !noundef !{} + %shl = shl i64 %arg0, %shift.amt + ret i64 %shl +} + +define i64 @shl_metadata_two_ranges(i64 %arg0, ptr %arg1.ptr) { +; CHECK-LABEL: shl_metadata_two_ranges: +; CHECK: ; %bb.0: +; CHECK-NEXT: s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0) +; CHECK-NEXT: flat_load_dword v1, v[2:3] +; CHECK-NEXT: s_waitcnt vmcnt(0) lgkmcnt(0) +; CHECK-NEXT: v_lshlrev_b32_e32 v1, v1, v0 +; CHECK-NEXT: v_mov_b32_e32 v0, 0 +; CHECK-NEXT: s_setpc_b64 s[30:31] + %shift.amt = load i64, ptr %arg1.ptr, !range !1, !noundef !{} + %shl = shl i64 %arg0, %shift.amt + ret i64 %shl +} + +; Known minimum is too low. Reduction must not be done. +define i64 @shl_metadata_out_of_range(i64 %arg0, ptr %arg1.ptr) { +; CHECK-LABEL: shl_metadata_out_of_range: +; CHECK: ; %bb.0: +; CHECK-NEXT: s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0) +; CHECK-NEXT: flat_load_dword v2, v[2:3] +; CHECK-NEXT: s_waitcnt vmcnt(0) lgkmcnt(0) +; CHECK-NEXT: v_lshlrev_b64 v[0:1], v2, v[0:1] +; CHECK-NEXT: s_setpc_b64 s[30:31] + %shift.amt = load i64, ptr %arg1.ptr, !range !2, !noundef !{} + %shl = shl i64 %arg0, %shift.amt + ret i64 %shl +} + +; Bounds cannot be truncated to i32 when load is narrowed to i32. +; Reduction must not be done. +; Bounds were chosen so that if bounds were truncated to i32 the +; known minimum would be 32 and the shl would be erroneously reduced. +define i64 @shl_metadata_cant_be_narrowed_to_i32(i64 %arg0, ptr %arg1.ptr) { +; CHECK-LABEL: shl_metadata_cant_be_narrowed_to_i32: +; CHECK: ; %bb.0: +; CHECK-NEXT: s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0) ; CHECK-NEXT: flat_load_dword v2, v[2:3] ; CHECK-NEXT: s_waitcnt vmcnt(0) lgkmcnt(0) ; CHECK-NEXT: v_lshlrev_b64 v[0:1], v2, v[0:1] ; CHECK-NEXT: s_setpc_b64 s[30:31] - %shift.amt = load i64, ptr %arg1.ptr, !range !0 + %shift.amt = load i64, ptr %arg1.ptr, !range !3, !noundef !{} %shl = shl i64 %arg0, %shift.amt ret i64 %shl } +; FIXME: This case should be reduced define <2 x i64> @shl_v2_metadata(<2 x i64> %arg0, ptr %arg1.ptr) { ; CHECK-LABEL: shl_v2_metadata: ; CHECK: ; %bb.0: @@ -39,11 +82,12 @@ define <2 x i64> @shl_v2_metadata(<2 x i64> %arg0, ptr %arg1.ptr) { ; CHECK-NEXT: v_lshlrev_b64 v[0:1], v4, v[0:1] ; CHECK-NEXT: v_lshlrev_b64 v[2:3], v6, v[2:3] ; CHECK-NEXT: s_setpc_b64 s[30:31] - %shift.amt = load <2 x i64>, ptr %arg1.ptr, !range !0 + %shift.amt = load <2 x i64>, ptr %arg1.ptr, !range !0, !noundef !{} %shl = shl <2 x i64> %arg0, %shift.amt ret <2 x i64> %shl } +; FIXME: This case should be reduced define <3 x i64> @shl_v3_metadata(<3 x i64> %arg0, ptr %arg1.ptr) { ; CHECK-LABEL: shl_v3_metadata: ; CHECK: ; %bb.0: @@ -55,11 +99,12 @@ define <3 x i64> @shl_v3_metadata(<3 x i64> %arg0, ptr %arg1.ptr) { ; CHECK-NEXT: v_lshlrev_b64 v[0:1], v8, v[0:1] ; CHECK-NEXT: v_lshlrev_b64 v[2:3], v10, v[2:3] ; CHECK-NEXT: s_setpc_b64 s[30:31] - %shift.amt = load <3 x i64>, ptr %arg1.ptr, !range !0 + %shift.amt = load <3 x i64>, ptr %arg1.ptr, !range !0, !noundef !{} %shl = shl <3 x i64> %arg0, %shift.amt ret <3 x i64> %shl } +; FIXME: This case should be reduced define <4 x i64> @shl_v4_metadata(<4 x i64> %arg0, ptr %arg1.ptr) { ; CHECK-LABEL: shl_v4_metadata: ; CHECK: ; %bb.0: @@ -74,12 +119,15 @@ define <4 x i64> @shl_v4_metadata(<4 x i64> %arg0, ptr %arg1.ptr) { ; CHECK-NEXT: v_lshlrev_b64 v[4:5], v13, v[4:5] ; CHECK-NEXT: v_lshlrev_b64 v[6:7], v15, v[6:7] ; CHECK-NEXT: s_setpc_b64 s[30:31] - %shift.amt = load <4 x i64>, ptr %arg1.ptr, !range !0 + %shift.amt = load <4 x i64>, ptr %arg1.ptr, !range !0, !noundef !{} %shl = shl <4 x i64> %arg0, %shift.amt ret <4 x i64> %shl } !0 = !{i64 32, i64 64} +!1 = !{i64 32, i64 38, i64 42, i64 48} +!2 = !{i64 31, i64 38, i64 42, i64 48} +!3 = !{i64 32, i64 38, i64 2147483680, i64 2147483681} ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ; Test range with an "or X, 16"