[RISCV][LegalizeTypes] Try to expand BSWAP before promoting if the promoted BSWAP...

If we're going to end up expanding anyway, we should do it early
so we don't create extra operations to handle the bytes added by
promotion.

This is helfpul on RISCV where we might have to promote i16 all
the way to i64.

Differential Revision: https://reviews.llvm.org/D95756

diff --git a/llvm/include/llvm/CodeGen/TargetLowering.h b/llvm/include/llvm/CodeGen/TargetLowering.h
index c3221aa..6eafc14 100644 (file)
--- a/llvm/include/llvm/CodeGen/TargetLowering.h
+++ b/llvm/include/llvm/CodeGen/TargetLowering.h
@@ -4396,6 +4396,12 @@ public:
   bool expandABS(SDNode *N, SDValue &Result, SelectionDAG &DAG,
                  bool IsNegative = false) const;
 
+  /// Expand BSWAP nodes. Expands scalar/vector BSWAP nodes with i16/i32/i64
+  /// scalar types. Returns SDValue() if expand fails.
+  /// \param N Node to expand
+  /// \returns The expansion result or SDValue() if it fails.
+  SDValue expandBSWAP(SDNode *N, SelectionDAG &DAG) const;
+
   /// Turn load of vector type into a load of the individual elements.
   /// \param LD load to expand
   /// \returns BUILD_VECTOR and TokenFactor nodes.

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 62d7191..a61e844 100644 (file)
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -182,7 +182,6 @@ private:
   SDValue PromoteLegalFP_TO_INT_SAT(SDNode *Node, const SDLoc &dl);
 
   SDValue ExpandBITREVERSE(SDValue Op, const SDLoc &dl);
-  SDValue ExpandBSWAP(SDValue Op, const SDLoc &dl);
   SDValue ExpandPARITY(SDValue Op, const SDLoc &dl);
 
   SDValue ExpandExtractFromVectorThroughStack(SDValue Op);
@@ -2846,58 +2845,6 @@ SDValue SelectionDAGLegalize::ExpandBITREVERSE(SDValue Op, const SDLoc &dl) {
   return Tmp;
 }
 
-/// Open code the operations for BSWAP of the specified operation.
-SDValue SelectionDAGLegalize::ExpandBSWAP(SDValue Op, const SDLoc &dl) {
-  EVT VT = Op.getValueType();
-  EVT SHVT = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
-  SDValue Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
-  switch (VT.getSimpleVT().getScalarType().SimpleTy) {
-  default: llvm_unreachable("Unhandled Expand type in BSWAP!");
-  case MVT::i16:
-    // Use a rotate by 8. This can be further expanded if necessary.
-    return DAG.getNode(ISD::ROTL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
-  case MVT::i32:
-    Tmp4 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
-    Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
-    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
-    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
-    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3,
-                       DAG.getConstant(0xFF0000, dl, VT));
-    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(0xFF00, dl, VT));
-    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
-    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
-    return DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
-  case MVT::i64:
-    Tmp8 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(56, dl, SHVT));
-    Tmp7 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(40, dl, SHVT));
-    Tmp6 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
-    Tmp5 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
-    Tmp4 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
-    Tmp3 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
-    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(40, dl, SHVT));
-    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(56, dl, SHVT));
-    Tmp7 = DAG.getNode(ISD::AND, dl, VT, Tmp7,
-                       DAG.getConstant(255ULL<<48, dl, VT));
-    Tmp6 = DAG.getNode(ISD::AND, dl, VT, Tmp6,
-                       DAG.getConstant(255ULL<<40, dl, VT));
-    Tmp5 = DAG.getNode(ISD::AND, dl, VT, Tmp5,
-                       DAG.getConstant(255ULL<<32, dl, VT));
-    Tmp4 = DAG.getNode(ISD::AND, dl, VT, Tmp4,
-                       DAG.getConstant(255ULL<<24, dl, VT));
-    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3,
-                       DAG.getConstant(255ULL<<16, dl, VT));
-    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2,
-                       DAG.getConstant(255ULL<<8 , dl, VT));
-    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp7);
-    Tmp6 = DAG.getNode(ISD::OR, dl, VT, Tmp6, Tmp5);
-    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
-    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
-    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp6);
-    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
-    return DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp4);
-  }
-}
-
 /// Open code the operations for PARITY of the specified operation.
 SDValue SelectionDAGLegalize::ExpandPARITY(SDValue Op, const SDLoc &dl) {
   EVT VT = Op.getValueType();
@@ -2949,7 +2896,8 @@ bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
     Results.push_back(ExpandBITREVERSE(Node->getOperand(0), dl));
     break;
   case ISD::BSWAP:
-    Results.push_back(ExpandBSWAP(Node->getOperand(0), dl));
+    if ((Tmp1 = TLI.expandBSWAP(Node, DAG)))
+      Results.push_back(Tmp1);
     break;
   case ISD::PARITY:
     Results.push_back(ExpandPARITY(Node->getOperand(0), dl));

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
index 4a686bc..cb7d464 100644 (file)
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -455,6 +455,15 @@ SDValue DAGTypeLegalizer::PromoteIntRes_BSWAP(SDNode *N) {
   EVT NVT = Op.getValueType();
   SDLoc dl(N);
 
+  // If the larger BSWAP isn't supported by the target, try to expand now.
+  // If we expand later we'll end up with more operations since we lost the
+  // original type. We only do this for scalars since we have a shuffle
+  // based lowering for vectors in LegalizeVectorOps.
+  if (!OVT.isVector() && !TLI.isOperationLegalOrCustom(ISD::BSWAP, NVT)) {
+    if (SDValue Res = TLI.expandBSWAP(N, DAG))
+      return DAG.getNode(ISD::ANY_EXTEND, dl, NVT, Res);
+  }
+
   unsigned DiffBits = NVT.getScalarSizeInBits() - OVT.getScalarSizeInBits();
   EVT ShiftVT = getShiftAmountTyForConstant(NVT, TLI, DAG);
   return DAG.getNode(ISD::SRL, dl, NVT, DAG.getNode(ISD::BSWAP, dl, NVT, Op),

diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 5760132..1e02c3c 100644 (file)
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -7006,6 +7006,64 @@ bool TargetLowering::expandABS(SDNode *N, SDValue &Result,
   return true;
 }
 
+SDValue TargetLowering::expandBSWAP(SDNode *N, SelectionDAG &DAG) const {
+  SDLoc dl(N);
+  EVT VT = N->getValueType(0);
+  SDValue Op = N->getOperand(0);
+
+  if (!VT.isSimple())
+    return SDValue();
+
+  EVT SHVT = getShiftAmountTy(VT, DAG.getDataLayout());
+  SDValue Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
+  switch (VT.getSimpleVT().getScalarType().SimpleTy) {
+  default:
+    return SDValue();
+  case MVT::i16:
+    // Use a rotate by 8. This can be further expanded if necessary.
+    return DAG.getNode(ISD::ROTL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
+  case MVT::i32:
+    Tmp4 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
+    Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
+    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
+    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
+    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3,
+                       DAG.getConstant(0xFF0000, dl, VT));
+    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(0xFF00, dl, VT));
+    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
+    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
+    return DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
+  case MVT::i64:
+    Tmp8 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(56, dl, SHVT));
+    Tmp7 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(40, dl, SHVT));
+    Tmp6 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
+    Tmp5 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
+    Tmp4 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
+    Tmp3 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
+    Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(40, dl, SHVT));
+    Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(56, dl, SHVT));
+    Tmp7 = DAG.getNode(ISD::AND, dl, VT, Tmp7,
+                       DAG.getConstant(255ULL<<48, dl, VT));
+    Tmp6 = DAG.getNode(ISD::AND, dl, VT, Tmp6,
+                       DAG.getConstant(255ULL<<40, dl, VT));
+    Tmp5 = DAG.getNode(ISD::AND, dl, VT, Tmp5,
+                       DAG.getConstant(255ULL<<32, dl, VT));
+    Tmp4 = DAG.getNode(ISD::AND, dl, VT, Tmp4,
+                       DAG.getConstant(255ULL<<24, dl, VT));
+    Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3,
+                       DAG.getConstant(255ULL<<16, dl, VT));
+    Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2,
+                       DAG.getConstant(255ULL<<8 , dl, VT));
+    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp7);
+    Tmp6 = DAG.getNode(ISD::OR, dl, VT, Tmp6, Tmp5);
+    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
+    Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
+    Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp6);
+    Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
+    return DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp4);
+  }
+}
+
 std::pair<SDValue, SDValue>
 TargetLowering::scalarizeVectorLoad(LoadSDNode *LD,
                                     SelectionDAG &DAG) const {

diff --git a/llvm/test/CodeGen/RISCV/bswap-ctlz-cttz-ctpop.ll b/llvm/test/CodeGen/RISCV/bswap-ctlz-cttz-ctpop.ll
index 7ec443c..db8b289 100644 (file)
--- a/llvm/test/CodeGen/RISCV/bswap-ctlz-cttz-ctpop.ll
+++ b/llvm/test/CodeGen/RISCV/bswap-ctlz-cttz-ctpop.ll
@@ -17,23 +17,22 @@ declare i32 @llvm.ctpop.i32(i32)
 define i16 @test_bswap_i16(i16 %a) nounwind {
 ; RV32I-LABEL: test_bswap_i16:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    slli a1, a0, 8
-; RV32I-NEXT:    lui a2, 4080
-; RV32I-NEXT:    and a1, a1, a2
-; RV32I-NEXT:    slli a0, a0, 24
+; RV32I-NEXT:    lui a1, 16
+; RV32I-NEXT:    addi a1, a1, -256
+; RV32I-NEXT:    and a1, a0, a1
+; RV32I-NEXT:    srli a1, a1, 8
+; RV32I-NEXT:    slli a0, a0, 8
 ; RV32I-NEXT:    or a0, a0, a1
-; RV32I-NEXT:    srli a0, a0, 16
 ; RV32I-NEXT:    ret
 ;
 ; RV64I-LABEL: test_bswap_i16:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a1, a0, 40
-; RV64I-NEXT:    addi a2, zero, 255
-; RV64I-NEXT:    slli a2, a2, 48
-; RV64I-NEXT:    and a1, a1, a2
-; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    lui a1, 16
+; RV64I-NEXT:    addiw a1, a1, -256
+; RV64I-NEXT:    and a1, a0, a1
+; RV64I-NEXT:    srli a1, a1, 8
+; RV64I-NEXT:    slli a0, a0, 8
 ; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    srli a0, a0, 48
 ; RV64I-NEXT:    ret
   %tmp = call i16 @llvm.bswap.i16(i16 %a)
   ret i16 %tmp
@@ -58,21 +57,18 @@ define i32 @test_bswap_i32(i32 %a) nounwind {
 ;
 ; RV64I-LABEL: test_bswap_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a1, a0, 8
-; RV64I-NEXT:    addi a2, zero, 255
-; RV64I-NEXT:    slli a3, a2, 32
-; RV64I-NEXT:    and a1, a1, a3
-; RV64I-NEXT:    slli a3, a0, 24
-; RV64I-NEXT:    slli a4, a2, 40
-; RV64I-NEXT:    and a3, a3, a4
-; RV64I-NEXT:    or a1, a3, a1
-; RV64I-NEXT:    slli a3, a0, 40
-; RV64I-NEXT:    slli a2, a2, 48
-; RV64I-NEXT:    and a2, a3, a2
-; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    srliw a1, a0, 8
+; RV64I-NEXT:    lui a2, 16
+; RV64I-NEXT:    addiw a2, a2, -256
+; RV64I-NEXT:    and a1, a1, a2
+; RV64I-NEXT:    srliw a2, a0, 24
+; RV64I-NEXT:    or a1, a1, a2
+; RV64I-NEXT:    slli a2, a0, 8
+; RV64I-NEXT:    lui a3, 4080
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    slli a0, a0, 24
 ; RV64I-NEXT:    or a0, a0, a2
 ; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    srli a0, a0, 32
 ; RV64I-NEXT:    ret
   %tmp = call i32 @llvm.bswap.i32(i32 %a)
   ret i32 %tmp

diff --git a/llvm/test/CodeGen/RISCV/rv64Zbb.ll b/llvm/test/CodeGen/RISCV/rv64Zbb.ll
index 64074a3..b0f0fb8 100644 (file)
--- a/llvm/test/CodeGen/RISCV/rv64Zbb.ll
+++ b/llvm/test/CodeGen/RISCV/rv64Zbb.ll
@@ -825,21 +825,19 @@ declare i32 @llvm.bswap.i32(i32)
 define signext i32 @bswap_i32(i32 signext %a) nounwind {
 ; RV64I-LABEL: bswap_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a1, a0, 8
-; RV64I-NEXT:    addi a2, zero, 255
-; RV64I-NEXT:    slli a3, a2, 32
-; RV64I-NEXT:    and a1, a1, a3
-; RV64I-NEXT:    slli a3, a0, 24
-; RV64I-NEXT:    slli a4, a2, 40
-; RV64I-NEXT:    and a3, a3, a4
-; RV64I-NEXT:    or a1, a3, a1
-; RV64I-NEXT:    slli a3, a0, 40
-; RV64I-NEXT:    slli a2, a2, 48
-; RV64I-NEXT:    and a2, a3, a2
-; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    srliw a1, a0, 8
+; RV64I-NEXT:    lui a2, 16
+; RV64I-NEXT:    addiw a2, a2, -256
+; RV64I-NEXT:    and a1, a1, a2
+; RV64I-NEXT:    srliw a2, a0, 24
+; RV64I-NEXT:    or a1, a1, a2
+; RV64I-NEXT:    slli a2, a0, 8
+; RV64I-NEXT:    lui a3, 4080
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    slli a0, a0, 24
 ; RV64I-NEXT:    or a0, a0, a2
 ; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    srai a0, a0, 32
+; RV64I-NEXT:    sext.w a0, a0
 ; RV64I-NEXT:    ret
 ;
 ; RV64IB-LABEL: bswap_i32:
@@ -860,21 +858,18 @@ define signext i32 @bswap_i32(i32 signext %a) nounwind {
 define void @bswap_i32_nosext(i32 signext %a, i32* %x) nounwind {
 ; RV64I-LABEL: bswap_i32_nosext:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a2, a0, 8
-; RV64I-NEXT:    addi a3, zero, 255
-; RV64I-NEXT:    slli a4, a3, 32
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    slli a4, a0, 24
-; RV64I-NEXT:    slli a5, a3, 40
-; RV64I-NEXT:    and a4, a4, a5
-; RV64I-NEXT:    or a2, a4, a2
-; RV64I-NEXT:    slli a4, a0, 40
-; RV64I-NEXT:    slli a3, a3, 48
-; RV64I-NEXT:    and a3, a4, a3
-; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    srliw a2, a0, 8
+; RV64I-NEXT:    lui a3, 16
+; RV64I-NEXT:    addiw a3, a3, -256
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    srliw a3, a0, 24
+; RV64I-NEXT:    or a2, a2, a3
+; RV64I-NEXT:    slli a3, a0, 8
+; RV64I-NEXT:    lui a4, 4080
+; RV64I-NEXT:    and a3, a3, a4
+; RV64I-NEXT:    slli a0, a0, 24
 ; RV64I-NEXT:    or a0, a0, a3
 ; RV64I-NEXT:    or a0, a0, a2
-; RV64I-NEXT:    srli a0, a0, 32
 ; RV64I-NEXT:    sw a0, 0(a1)
 ; RV64I-NEXT:    ret
 ;

diff --git a/llvm/test/CodeGen/RISCV/rv64Zbp.ll b/llvm/test/CodeGen/RISCV/rv64Zbp.ll
index d2191af..101ce0e 100644 (file)
--- a/llvm/test/CodeGen/RISCV/rv64Zbp.ll
+++ b/llvm/test/CodeGen/RISCV/rv64Zbp.ll
@@ -2981,21 +2981,19 @@ declare i32 @llvm.bswap.i32(i32)
 define signext i32 @bswap_i32(i32 signext %a) nounwind {
 ; RV64I-LABEL: bswap_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a1, a0, 8
-; RV64I-NEXT:    addi a2, zero, 255
-; RV64I-NEXT:    slli a3, a2, 32
-; RV64I-NEXT:    and a1, a1, a3
-; RV64I-NEXT:    slli a3, a0, 24
-; RV64I-NEXT:    slli a4, a2, 40
-; RV64I-NEXT:    and a3, a3, a4
-; RV64I-NEXT:    or a1, a3, a1
-; RV64I-NEXT:    slli a3, a0, 40
-; RV64I-NEXT:    slli a2, a2, 48
-; RV64I-NEXT:    and a2, a3, a2
-; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    srliw a1, a0, 8
+; RV64I-NEXT:    lui a2, 16
+; RV64I-NEXT:    addiw a2, a2, -256
+; RV64I-NEXT:    and a1, a1, a2
+; RV64I-NEXT:    srliw a2, a0, 24
+; RV64I-NEXT:    or a1, a1, a2
+; RV64I-NEXT:    slli a2, a0, 8
+; RV64I-NEXT:    lui a3, 4080
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    slli a0, a0, 24
 ; RV64I-NEXT:    or a0, a0, a2
 ; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    srai a0, a0, 32
+; RV64I-NEXT:    sext.w a0, a0
 ; RV64I-NEXT:    ret
 ;
 ; RV64IB-LABEL: bswap_i32:
@@ -3015,21 +3013,18 @@ define signext i32 @bswap_i32(i32 signext %a) nounwind {
 define void @bswap_i32_nosext(i32 signext %a, i32* %x) nounwind {
 ; RV64I-LABEL: bswap_i32_nosext:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    slli a2, a0, 8
-; RV64I-NEXT:    addi a3, zero, 255
-; RV64I-NEXT:    slli a4, a3, 32
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    slli a4, a0, 24
-; RV64I-NEXT:    slli a5, a3, 40
-; RV64I-NEXT:    and a4, a4, a5
-; RV64I-NEXT:    or a2, a4, a2
-; RV64I-NEXT:    slli a4, a0, 40
-; RV64I-NEXT:    slli a3, a3, 48
-; RV64I-NEXT:    and a3, a4, a3
-; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    srliw a2, a0, 8
+; RV64I-NEXT:    lui a3, 16
+; RV64I-NEXT:    addiw a3, a3, -256
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    srliw a3, a0, 24
+; RV64I-NEXT:    or a2, a2, a3
+; RV64I-NEXT:    slli a3, a0, 8
+; RV64I-NEXT:    lui a4, 4080
+; RV64I-NEXT:    and a3, a3, a4
+; RV64I-NEXT:    slli a0, a0, 24
 ; RV64I-NEXT:    or a0, a0, a3
 ; RV64I-NEXT:    or a0, a0, a2
-; RV64I-NEXT:    srli a0, a0, 32
 ; RV64I-NEXT:    sw a0, 0(a1)
 ; RV64I-NEXT:    ret
 ;
@@ -3422,39 +3417,20 @@ define i64 @bitreverse_i64(i64 %a) nounwind {
 define i32 @bswap_rotr_i32(i32 %a) {
 ; RV64I-LABEL: bswap_rotr_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    srli a1, a0, 24
-; RV64I-NEXT:    lui a2, 4080
+; RV64I-NEXT:    srliw a1, a0, 8
+; RV64I-NEXT:    lui a2, 16
+; RV64I-NEXT:    addiw a2, a2, -256
 ; RV64I-NEXT:    and a1, a1, a2
-; RV64I-NEXT:    srli a2, a0, 8
-; RV64I-NEXT:    addi a3, zero, 255
-; RV64I-NEXT:    slli a4, a3, 24
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    or a1, a2, a1
-; RV64I-NEXT:    srli a2, a0, 40
-; RV64I-NEXT:    lui a4, 16
-; RV64I-NEXT:    addiw a4, a4, -256
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    srli a4, a0, 56
-; RV64I-NEXT:    or a2, a2, a4
+; RV64I-NEXT:    srliw a2, a0, 24
 ; RV64I-NEXT:    or a1, a1, a2
 ; RV64I-NEXT:    slli a2, a0, 8
-; RV64I-NEXT:    slli a4, a3, 32
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    slli a4, a0, 24
-; RV64I-NEXT:    slli a5, a3, 40
-; RV64I-NEXT:    and a4, a4, a5
-; RV64I-NEXT:    or a2, a4, a2
-; RV64I-NEXT:    slli a4, a0, 40
-; RV64I-NEXT:    slli a3, a3, 48
-; RV64I-NEXT:    and a3, a4, a3
-; RV64I-NEXT:    slli a0, a0, 56
-; RV64I-NEXT:    or a0, a0, a3
+; RV64I-NEXT:    lui a3, 4080
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    slli a0, a0, 24
 ; RV64I-NEXT:    or a0, a0, a2
-; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    srli a1, a0, 16
-; RV64I-NEXT:    lui a2, 1048560
-; RV64I-NEXT:    and a1, a1, a2
-; RV64I-NEXT:    srli a0, a0, 48
+; RV64I-NEXT:    or a1, a0, a1
+; RV64I-NEXT:    slli a1, a1, 16
+; RV64I-NEXT:    srliw a0, a0, 16
 ; RV64I-NEXT:    or a0, a0, a1
 ; RV64I-NEXT:    ret
 ;
@@ -3475,39 +3451,20 @@ define i32 @bswap_rotr_i32(i32 %a) {
 define i32 @bswap_rotl_i32(i32 %a) {
 ; RV64I-LABEL: bswap_rotl_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    srli a1, a0, 24
-; RV64I-NEXT:    lui a2, 4080
+; RV64I-NEXT:    srliw a1, a0, 8
+; RV64I-NEXT:    lui a2, 16
+; RV64I-NEXT:    addiw a2, a2, -256
 ; RV64I-NEXT:    and a1, a1, a2
-; RV64I-NEXT:    srli a2, a0, 8
-; RV64I-NEXT:    addi a3, zero, 255
-; RV64I-NEXT:    slli a4, a3, 24
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    or a1, a2, a1
-; RV64I-NEXT:    srli a2, a0, 40
-; RV64I-NEXT:    lui a4, 16
-; RV64I-NEXT:    addiw a4, a4, -256
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    srli a4, a0, 56
-; RV64I-NEXT:    or a2, a2, a4
+; RV64I-NEXT:    srliw a2, a0, 24
 ; RV64I-NEXT:    or a1, a1, a2
 ; RV64I-NEXT:    slli a2, a0, 8
-; RV64I-NEXT:    slli a4, a3, 32
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    slli a4, a0, 24
-; RV64I-NEXT:    slli a5, a3, 40
-; RV64I-NEXT:    and a4, a4, a5
-; RV64I-NEXT:    or a2, a4, a2
-; RV64I-NEXT:    slli a4, a0, 40
-; RV64I-NEXT:    slli a3, a3, 48
-; RV64I-NEXT:    and a3, a4, a3
-; RV64I-NEXT:    slli a0, a0, 56
-; RV64I-NEXT:    or a0, a0, a3
+; RV64I-NEXT:    lui a3, 4080
+; RV64I-NEXT:    and a2, a2, a3
+; RV64I-NEXT:    slli a0, a0, 24
 ; RV64I-NEXT:    or a0, a0, a2
-; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    srli a1, a0, 16
-; RV64I-NEXT:    lui a2, 1048560
-; RV64I-NEXT:    and a1, a1, a2
-; RV64I-NEXT:    srli a0, a0, 48
+; RV64I-NEXT:    or a1, a0, a1
+; RV64I-NEXT:    slli a1, a1, 16
+; RV64I-NEXT:    srliw a0, a0, 16
 ; RV64I-NEXT:    or a0, a1, a0
 ; RV64I-NEXT:    ret
 ;
@@ -3528,35 +3485,35 @@ define i32 @bswap_rotl_i32(i32 %a) {
 define i32 @bitreverse_bswap_i32(i32 %a) {
 ; RV64I-LABEL: bitreverse_bswap_i32:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    srli a1, a0, 24
-; RV64I-NEXT:    lui a2, 4080
-; RV64I-NEXT:    and a1, a1, a2
-; RV64I-NEXT:    srli a2, a0, 8
-; RV64I-NEXT:    addi a3, zero, 255
-; RV64I-NEXT:    slli a4, a3, 24
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    or a1, a2, a1
-; RV64I-NEXT:    srli a2, a0, 40
-; RV64I-NEXT:    lui a4, 16
-; RV64I-NEXT:    addiw a4, a4, -256
-; RV64I-NEXT:    and a2, a2, a4
-; RV64I-NEXT:    srli a4, a0, 56
-; RV64I-NEXT:    or a2, a2, a4
-; RV64I-NEXT:    or a4, a1, a2
-; RV64I-NEXT:    slli a1, a0, 8
-; RV64I-NEXT:    slli a2, a3, 32
-; RV64I-NEXT:    and a2, a1, a2
+; RV64I-NEXT:    srli a2, a0, 24
+; RV64I-NEXT:    lui a6, 4080
+; RV64I-NEXT:    and a2, a2, a6
+; RV64I-NEXT:    srli a3, a0, 8
+; RV64I-NEXT:    addi a4, zero, 255
+; RV64I-NEXT:    slli a5, a4, 24
+; RV64I-NEXT:    and a3, a3, a5
+; RV64I-NEXT:    or a3, a3, a2
+; RV64I-NEXT:    srli a5, a0, 40
+; RV64I-NEXT:    lui a2, 16
+; RV64I-NEXT:    addiw a7, a2, -256
+; RV64I-NEXT:    and a5, a5, a7
+; RV64I-NEXT:    srli a1, a0, 56
+; RV64I-NEXT:    or a1, a5, a1
+; RV64I-NEXT:    or a1, a3, a1
+; RV64I-NEXT:    slli a3, a0, 8
+; RV64I-NEXT:    slli a5, a4, 32
+; RV64I-NEXT:    and a3, a3, a5
 ; RV64I-NEXT:    slli a5, a0, 24
-; RV64I-NEXT:    slli a6, a3, 40
-; RV64I-NEXT:    and a5, a5, a6
-; RV64I-NEXT:    or a5, a5, a2
-; RV64I-NEXT:    slli a1, a0, 40
-; RV64I-NEXT:    slli a2, a3, 48
-; RV64I-NEXT:    and a1, a1, a2
+; RV64I-NEXT:    slli a2, a4, 40
+; RV64I-NEXT:    and a2, a5, a2
+; RV64I-NEXT:    or a2, a2, a3
+; RV64I-NEXT:    slli a3, a0, 40
+; RV64I-NEXT:    slli a4, a4, 48
+; RV64I-NEXT:    and a3, a3, a4
 ; RV64I-NEXT:    slli a0, a0, 56
+; RV64I-NEXT:    or a0, a0, a3
+; RV64I-NEXT:    or a0, a0, a2
 ; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    or a0, a0, a5
-; RV64I-NEXT:    or a0, a0, a4
 ; RV64I-NEXT:    lui a1, 3855
 ; RV64I-NEXT:    addiw a1, a1, 241
 ; RV64I-NEXT:    slli a1, a1, 12
@@ -3567,15 +3524,15 @@ define i32 @bitreverse_bswap_i32(i32 %a) {
 ; RV64I-NEXT:    addi a1, a1, -241
 ; RV64I-NEXT:    and a1, a0, a1
 ; RV64I-NEXT:    slli a1, a1, 4
-; RV64I-NEXT:    lui a3, 1044721
-; RV64I-NEXT:    addiw a3, a3, -241
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, 241
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, -241
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, 240
-; RV64I-NEXT:    and a0, a0, a3
+; RV64I-NEXT:    lui a2, 1044721
+; RV64I-NEXT:    addiw a2, a2, -241
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, 241
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -241
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, 240
+; RV64I-NEXT:    and a0, a0, a2
 ; RV64I-NEXT:    srli a0, a0, 4
 ; RV64I-NEXT:    or a0, a0, a1
 ; RV64I-NEXT:    lui a1, 13107
@@ -3588,15 +3545,15 @@ define i32 @bitreverse_bswap_i32(i32 %a) {
 ; RV64I-NEXT:    addi a1, a1, 819
 ; RV64I-NEXT:    and a1, a0, a1
 ; RV64I-NEXT:    slli a1, a1, 2
-; RV64I-NEXT:    lui a3, 1035469
-; RV64I-NEXT:    addiw a3, a3, -819
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, -819
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, -819
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, -820
-; RV64I-NEXT:    and a0, a0, a3
+; RV64I-NEXT:    lui a2, 1035469
+; RV64I-NEXT:    addiw a2, a2, -819
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -819
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -819
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -820
+; RV64I-NEXT:    and a0, a0, a2
 ; RV64I-NEXT:    srli a0, a0, 2
 ; RV64I-NEXT:    or a0, a0, a1
 ; RV64I-NEXT:    lui a1, 21845
@@ -3609,30 +3566,28 @@ define i32 @bitreverse_bswap_i32(i32 %a) {
 ; RV64I-NEXT:    addi a1, a1, 1365
 ; RV64I-NEXT:    and a1, a0, a1
 ; RV64I-NEXT:    slli a1, a1, 1
-; RV64I-NEXT:    lui a3, 1026731
-; RV64I-NEXT:    addiw a3, a3, -1365
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, -1365
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, -1365
-; RV64I-NEXT:    slli a3, a3, 12
-; RV64I-NEXT:    addi a3, a3, -1366
-; RV64I-NEXT:    and a0, a0, a3
+; RV64I-NEXT:    lui a2, 1026731
+; RV64I-NEXT:    addiw a2, a2, -1365
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -1365
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -1365
+; RV64I-NEXT:    slli a2, a2, 12
+; RV64I-NEXT:    addi a2, a2, -1366
+; RV64I-NEXT:    and a0, a0, a2
 ; RV64I-NEXT:    srli a0, a0, 1
 ; RV64I-NEXT:    or a0, a0, a1
-; RV64I-NEXT:    slli a1, a0, 24
-; RV64I-NEXT:    addi a3, zero, -1
-; RV64I-NEXT:    slli a3, a3, 56
-; RV64I-NEXT:    and a1, a1, a3
-; RV64I-NEXT:    srli a3, a0, 8
-; RV64I-NEXT:    and a3, a3, a6
-; RV64I-NEXT:    srli a4, a0, 24
-; RV64I-NEXT:    or a3, a3, a4
-; RV64I-NEXT:    slli a0, a0, 8
-; RV64I-NEXT:    and a0, a0, a2
+; RV64I-NEXT:    srli a1, a0, 8
+; RV64I-NEXT:    lui a2, 1044480
+; RV64I-NEXT:    and a1, a1, a2
+; RV64I-NEXT:    srli a2, a0, 40
+; RV64I-NEXT:    and a2, a2, a7
+; RV64I-NEXT:    srli a3, a0, 56
+; RV64I-NEXT:    or a2, a2, a3
+; RV64I-NEXT:    srli a0, a0, 24
+; RV64I-NEXT:    and a0, a0, a6
 ; RV64I-NEXT:    or a0, a1, a0
-; RV64I-NEXT:    or a0, a0, a3
-; RV64I-NEXT:    srli a0, a0, 32
+; RV64I-NEXT:    or a0, a0, a2
 ; RV64I-NEXT:    ret
 ;
 ; RV64IB-LABEL: bitreverse_bswap_i32: