[llvm] 5decab1 - AMDGPU: Reduce shl64 to shl32 if shift range is [63-32] (#125574)

via llvm-commits llvm-commits at lists.llvm.org
Thu Feb 13 11:40:28 PST 2025


Author: LU-JOHN
Date: 2025-02-13T13:40:25-06:00
New Revision: 5decab178f2642a49037c33f00726792b7fdf4a3

URL: https://github.com/llvm/llvm-project/commit/5decab178f2642a49037c33f00726792b7fdf4a3
DIFF: https://github.com/llvm/llvm-project/commit/5decab178f2642a49037c33f00726792b7fdf4a3.diff

LOG: AMDGPU: Reduce shl64 to shl32 if shift range is [63-32] (#125574)

Reduce:

   DST = shl i64 X, Y

where Y is in the range [63-32] to:

   DST = [0, shl i32 X, (Y & 32)]


Alive2 analysis:

https://alive2.llvm.org/ce/z/w_u5je

---------

Signed-off-by: John Lu <John.Lu at amd.com>

Added: 
    llvm/test/CodeGen/AMDGPU/shl64_reduce.ll
    llvm/test/CodeGen/AMDGPU/shl64_reduce_flags.ll

Modified: 
    llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
index 792e17eeedab1..2d46cf3b70a34 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
@@ -4040,47 +4040,48 @@ SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
                                                 DAGCombinerInfo &DCI) const {
   EVT VT = N->getValueType(0);
-
-  ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
-  if (!RHS)
-    return SDValue();
-
   SDValue LHS = N->getOperand(0);
-  unsigned RHSVal = RHS->getZExtValue();
-  if (!RHSVal)
-    return LHS;
-
+  SDValue RHS = N->getOperand(1);
+  ConstantSDNode *CRHS = dyn_cast<ConstantSDNode>(RHS);
   SDLoc SL(N);
   SelectionDAG &DAG = DCI.DAG;
 
-  switch (LHS->getOpcode()) {
-  default:
-    break;
-  case ISD::ZERO_EXTEND:
-  case ISD::SIGN_EXTEND:
-  case ISD::ANY_EXTEND: {
-    SDValue X = LHS->getOperand(0);
-
-    if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
-        isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
-      // Prefer build_vector as the canonical form if packed types are legal.
-      // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
-      SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
-       { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
-      return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
-    }
+  unsigned RHSVal;
+  if (CRHS) {
+    RHSVal = CRHS->getZExtValue();
+    if (!RHSVal)
+      return LHS;
 
-    // shl (ext x) => zext (shl x), if shift does not overflow int
-    if (VT != MVT::i64)
-      break;
-    KnownBits Known = DAG.computeKnownBits(X);
-    unsigned LZ = Known.countMinLeadingZeros();
-    if (LZ < RHSVal)
+    switch (LHS->getOpcode()) {
+    default:
       break;
-    EVT XVT = X.getValueType();
-    SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
-    return DAG.getZExtOrTrunc(Shl, SL, VT);
-  }
+    case ISD::ZERO_EXTEND:
+    case ISD::SIGN_EXTEND:
+    case ISD::ANY_EXTEND: {
+      SDValue X = LHS->getOperand(0);
+
+      if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
+          isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
+        // Prefer build_vector as the canonical form if packed types are legal.
+        // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
+        SDValue Vec = DAG.getBuildVector(
+            MVT::v2i16, SL,
+            {DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0)});
+        return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
+      }
+
+      // shl (ext x) => zext (shl x), if shift does not overflow int
+      if (VT != MVT::i64)
+        break;
+      KnownBits Known = DAG.computeKnownBits(X);
+      unsigned LZ = Known.countMinLeadingZeros();
+      if (LZ < RHSVal)
+        break;
+      EVT XVT = X.getValueType();
+      SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(CRHS, 0));
+      return DAG.getZExtOrTrunc(Shl, SL, VT);
+    }
+    }
   }
 
   if (VT != MVT::i64)
@@ -4091,18 +4092,34 @@ SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
   // common case, splitting this into a move and a 32-bit shift is faster and
   // the same code size.
-  if (RHSVal < 32)
+  EVT TargetType = VT.getHalfSizedIntegerVT(*DAG.getContext());
+  EVT TargetVecPairType = EVT::getVectorVT(*DAG.getContext(), TargetType, 2);
+  KnownBits Known = DAG.computeKnownBits(RHS);
+
+  if (Known.getMinValue().getZExtValue() < TargetType.getSizeInBits())
     return SDValue();
+  SDValue ShiftAmt;
 
-  SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
+  if (CRHS) {
+    ShiftAmt =
+        DAG.getConstant(RHSVal - TargetType.getSizeInBits(), SL, TargetType);
+  } else {
+    SDValue truncShiftAmt = DAG.getNode(ISD::TRUNCATE, SL, TargetType, RHS);
+    const SDValue ShiftMask =
+        DAG.getConstant(TargetType.getSizeInBits() - 1, SL, TargetType);
+    // This AND instruction will clamp out of bounds shift values.
+    // It will also be removed during later instruction selection.
+    ShiftAmt = DAG.getNode(ISD::AND, SL, TargetType, truncShiftAmt, ShiftMask);
+  }
 
-  SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
-  SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
+  SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, TargetType, LHS);
+  SDValue NewShift =
+      DAG.getNode(ISD::SHL, SL, TargetType, Lo, ShiftAmt, N->getFlags());
 
-  const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
+  const SDValue Zero = DAG.getConstant(0, SL, TargetType);
 
-  SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
-  return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
+  SDValue Vec = DAG.getBuildVector(TargetVecPairType, SL, {Zero, NewShift});
+  return DAG.getNode(ISD::BITCAST, SL, VT, Vec);
 }
 
 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,

diff  --git a/llvm/test/CodeGen/AMDGPU/shl64_reduce.ll b/llvm/test/CodeGen/AMDGPU/shl64_reduce.ll
new file mode 100644
index 0000000000000..05430213c17d2
--- /dev/null
+++ b/llvm/test/CodeGen/AMDGPU/shl64_reduce.ll
@@ -0,0 +1,477 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+;; Test reduction of:
+;;
+;;   DST = shl i64 X, Y
+;;
+;; where Y is in the range [63-32] to:
+;;
+;;   DST = [0, shl i32 X, (Y & 0x1F)]
+
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 < %s | FileCheck %s
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; 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 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
+  %shl = shl i64 %arg0, %shift.amt
+  ret i64 %shl
+}
+
+define <2 x i64> @shl_v2_metadata(<2 x i64> %arg0, ptr %arg1.ptr) {
+; CHECK-LABEL: shl_v2_metadata:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    flat_load_dwordx4 v[4:7], v[4:5]
+; CHECK-NEXT:    s_waitcnt vmcnt(0) lgkmcnt(0)
+; 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
+  %shl = shl <2 x i64> %arg0, %shift.amt
+  ret <2 x i64> %shl
+}
+
+define <3 x i64> @shl_v3_metadata(<3 x i64> %arg0, ptr %arg1.ptr) {
+; CHECK-LABEL: shl_v3_metadata:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    flat_load_dword v12, v[6:7] offset:16
+; CHECK-NEXT:    flat_load_dwordx4 v[8:11], v[6:7]
+; CHECK-NEXT:    s_waitcnt vmcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_lshlrev_b64 v[4:5], v12, v[4:5]
+; 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
+  %shl = shl <3 x i64> %arg0, %shift.amt
+  ret <3 x i64> %shl
+}
+
+define <4 x i64> @shl_v4_metadata(<4 x i64> %arg0, ptr %arg1.ptr) {
+; CHECK-LABEL: shl_v4_metadata:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    flat_load_dwordx4 v[10:13], v[8:9]
+; CHECK-NEXT:    s_waitcnt vmcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    flat_load_dwordx4 v[13:16], v[8:9] offset:16
+; CHECK-NEXT:    ; kill: killed $vgpr8 killed $vgpr9
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v10, v[0:1]
+; CHECK-NEXT:    v_lshlrev_b64 v[2:3], v12, v[2:3]
+; CHECK-NEXT:    s_waitcnt vmcnt(0) lgkmcnt(0)
+; 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
+  %shl = shl <4 x i64> %arg0, %shift.amt
+  ret <4 x i64> %shl
+}
+
+!0 = !{i64 32, i64 64}
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; Test range with an "or X, 16"
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+; These cases must not be reduced because the known minimum, 16, is not in range.
+
+define i64 @shl_or16(i64 %arg0, i64 %shift_amt) {
+; CHECK-LABEL: shl_or16:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_or_b32_e32 v2, 16, v2
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v2, v[0:1]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or i64 %shift_amt, 16
+  %shl = shl i64 %arg0, %or
+  ret i64 %shl
+}
+
+define <2 x i64> @shl_v2_or16(<2 x i64> %arg0, <2 x i64> %shift_amt) {
+; CHECK-LABEL: shl_v2_or16:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_or_b32_e32 v5, 16, v6
+; CHECK-NEXT:    v_or_b32_e32 v4, 16, v4
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v4, v[0:1]
+; CHECK-NEXT:    v_lshlrev_b64 v[2:3], v5, v[2:3]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <2 x i64> %shift_amt, splat (i64 16)
+  %shl = shl <2 x i64> %arg0, %or
+  ret <2 x i64> %shl
+}
+
+define <3 x i64> @shl_v3_or16(<3 x i64> %arg0, <3 x i64> %shift_amt) {
+; CHECK-LABEL: shl_v3_or16:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_or_b32_e32 v7, 16, v10
+; CHECK-NEXT:    v_or_b32_e32 v8, 16, v8
+; CHECK-NEXT:    v_or_b32_e32 v6, 16, v6
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v6, v[0:1]
+; CHECK-NEXT:    v_lshlrev_b64 v[2:3], v8, v[2:3]
+; CHECK-NEXT:    v_lshlrev_b64 v[4:5], v7, v[4:5]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <3 x i64> %shift_amt, splat (i64 16)
+  %shl = shl <3 x i64> %arg0, %or
+  ret <3 x i64> %shl
+}
+
+define <4 x i64> @shl_v4_or16(<4 x i64> %arg0, <4 x i64> %shift_amt) {
+; CHECK-LABEL: shl_v4_or16:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_or_b32_e32 v9, 16, v14
+; CHECK-NEXT:    v_or_b32_e32 v11, 16, v12
+; CHECK-NEXT:    v_or_b32_e32 v10, 16, v10
+; CHECK-NEXT:    v_or_b32_e32 v8, 16, v8
+; 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:    v_lshlrev_b64 v[4:5], v11, v[4:5]
+; CHECK-NEXT:    v_lshlrev_b64 v[6:7], v9, v[6:7]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <4 x i64> %shift_amt, splat (i64 16)
+  %shl = shl <4 x i64> %arg0, %or
+  ret <4 x i64> %shl
+}
+
+; test SGPR
+
+define i64 @shl_or16_sgpr(i64 inreg %arg0, i64 inreg %shift_amt) {
+; CHECK-LABEL: shl_or16_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_or_b32 s4, s18, 16
+; CHECK-NEXT:    s_lshl_b64 s[4:5], s[16:17], s4
+; CHECK-NEXT:    v_mov_b32_e32 v0, s4
+; CHECK-NEXT:    v_mov_b32_e32 v1, s5
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or i64 %shift_amt, 16
+  %shl = shl i64 %arg0, %or
+  ret i64 %shl
+}
+
+define <2 x i64> @shl_v2_or16_sgpr(<2 x i64> inreg %arg0, <2 x i64> inreg %shift_amt) {
+; CHECK-LABEL: shl_v2_or16_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_or_b32 s6, s22, 16
+; CHECK-NEXT:    s_or_b32 s4, s20, 16
+; CHECK-NEXT:    s_lshl_b64 s[4:5], s[16:17], s4
+; CHECK-NEXT:    s_lshl_b64 s[6:7], s[18:19], s6
+; CHECK-NEXT:    v_mov_b32_e32 v0, s4
+; CHECK-NEXT:    v_mov_b32_e32 v1, s5
+; CHECK-NEXT:    v_mov_b32_e32 v2, s6
+; CHECK-NEXT:    v_mov_b32_e32 v3, s7
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <2 x i64> %shift_amt, splat (i64 16)
+  %shl = shl <2 x i64> %arg0, %or
+  ret <2 x i64> %shl
+}
+
+define <3 x i64> @shl_v3_or16_sgpr(<3 x i64> inreg %arg0, <3 x i64> inreg %shift_amt) {
+; CHECK-LABEL: shl_v3_or16_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_or_b32 s8, s26, 16
+; CHECK-NEXT:    s_or_b32 s6, s24, 16
+; CHECK-NEXT:    s_or_b32 s4, s22, 16
+; CHECK-NEXT:    s_lshl_b64 s[4:5], s[16:17], s4
+; CHECK-NEXT:    s_lshl_b64 s[6:7], s[18:19], s6
+; CHECK-NEXT:    s_lshl_b64 s[8:9], s[20:21], s8
+; CHECK-NEXT:    v_mov_b32_e32 v0, s4
+; CHECK-NEXT:    v_mov_b32_e32 v1, s5
+; CHECK-NEXT:    v_mov_b32_e32 v2, s6
+; CHECK-NEXT:    v_mov_b32_e32 v3, s7
+; CHECK-NEXT:    v_mov_b32_e32 v4, s8
+; CHECK-NEXT:    v_mov_b32_e32 v5, s9
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <3 x i64> %shift_amt, splat (i64 16)
+  %shl = shl <3 x i64> %arg0, %or
+  ret <3 x i64> %shl
+}
+
+define <4 x i64> @shl_v4_or16_sgpr(<4 x i64> inreg %arg0, <4 x i64> inreg %shift_amt) {
+; CHECK-LABEL: shl_v4_or16_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_or_b32_e32 v0, 16, v0
+; CHECK-NEXT:    s_or_b32 s8, s28, 16
+; CHECK-NEXT:    s_or_b32 s6, s26, 16
+; CHECK-NEXT:    s_or_b32 s4, s24, 16
+; CHECK-NEXT:    s_lshl_b64 s[4:5], s[16:17], s4
+; CHECK-NEXT:    s_lshl_b64 s[6:7], s[18:19], s6
+; CHECK-NEXT:    s_lshl_b64 s[8:9], s[20:21], s8
+; CHECK-NEXT:    v_lshlrev_b64 v[6:7], v0, s[22:23]
+; CHECK-NEXT:    v_mov_b32_e32 v0, s4
+; CHECK-NEXT:    v_mov_b32_e32 v1, s5
+; CHECK-NEXT:    v_mov_b32_e32 v2, s6
+; CHECK-NEXT:    v_mov_b32_e32 v3, s7
+; CHECK-NEXT:    v_mov_b32_e32 v4, s8
+; CHECK-NEXT:    v_mov_b32_e32 v5, s9
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <4 x i64> %shift_amt, splat (i64 16)
+  %shl = shl <4 x i64> %arg0, %or
+  ret <4 x i64> %shl
+}
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; Test range with an "or X, 32"
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+; These cases are reduced because computeKnownBits() can calculate a minimum of 32
+; based on the OR with 32.
+
+define i64 @shl_or32(i64 %arg0, i64 %shift_amt) {
+; CHECK-LABEL: shl_or32:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_lshlrev_b32_e32 v1, v2, v0
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or i64 %shift_amt, 32
+  %shl = shl i64 %arg0, %or
+  ret i64 %shl
+}
+
+define <2 x i64> @shl_v2_or32(<2 x i64> %arg0, <2 x i64> %shift_amt) {
+; CHECK-LABEL: shl_v2_or32:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_lshlrev_b32_e32 v1, v4, v0
+; CHECK-NEXT:    v_lshlrev_b32_e32 v3, v6, v2
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <2 x i64> %shift_amt, splat (i64 32)
+  %shl = shl <2 x i64> %arg0, %or
+  ret <2 x i64> %shl
+}
+
+define <3 x i64> @shl_v3_or32(<3 x i64> %arg0, <3 x i64> %shift_amt) {
+; CHECK-LABEL: shl_v3_or32:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_lshlrev_b32_e32 v1, v6, v0
+; CHECK-NEXT:    v_lshlrev_b32_e32 v3, v8, v2
+; CHECK-NEXT:    v_lshlrev_b32_e32 v5, v10, v4
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    v_mov_b32_e32 v4, 0
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <3 x i64> %shift_amt, splat (i64 32)
+  %shl = shl <3 x i64> %arg0, %or
+  ret <3 x i64> %shl
+}
+
+define <4 x i64> @shl_v4_or32(<4 x i64> %arg0, <4 x i64> %shift_amt) {
+; CHECK-LABEL: shl_v4_or32:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_lshlrev_b32_e32 v1, v8, v0
+; CHECK-NEXT:    v_lshlrev_b32_e32 v3, v10, v2
+; CHECK-NEXT:    v_lshlrev_b32_e32 v5, v12, v4
+; CHECK-NEXT:    v_lshlrev_b32_e32 v7, v14, v6
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    v_mov_b32_e32 v4, 0
+; CHECK-NEXT:    v_mov_b32_e32 v6, 0
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <4 x i64> %shift_amt, splat (i64 32)
+  %shl = shl <4 x i64> %arg0, %or
+  ret <4 x i64> %shl
+}
+
+; test SGPR
+
+define i64 @shl_or32_sgpr(i64 inreg %arg0, i64 inreg %shift_amt) {
+; CHECK-LABEL: shl_or32_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_lshl_b32 s4, s16, s18
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    v_mov_b32_e32 v1, s4
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or i64 %shift_amt, 32
+  %shl = shl i64 %arg0, %or
+  ret i64 %shl
+}
+
+define <2 x i64> @shl_v2_or32_sgpr(<2 x i64> inreg %arg0, <2 x i64> inreg %shift_amt) {
+; CHECK-LABEL: shl_v2_or32_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_lshl_b32 s4, s16, s20
+; CHECK-NEXT:    s_lshl_b32 s5, s18, s22
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    v_mov_b32_e32 v1, s4
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    v_mov_b32_e32 v3, s5
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <2 x i64> %shift_amt, splat (i64 32)
+  %shl = shl <2 x i64> %arg0, %or
+  ret <2 x i64> %shl
+}
+
+define <3 x i64> @shl_v3_or32_sgpr(<3 x i64> inreg %arg0, <3 x i64> inreg %shift_amt) {
+; CHECK-LABEL: shl_v3_or32_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_lshl_b32 s4, s16, s22
+; CHECK-NEXT:    s_lshl_b32 s5, s18, s24
+; CHECK-NEXT:    s_lshl_b32 s6, s20, s26
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    v_mov_b32_e32 v1, s4
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    v_mov_b32_e32 v3, s5
+; CHECK-NEXT:    v_mov_b32_e32 v4, 0
+; CHECK-NEXT:    v_mov_b32_e32 v5, s6
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <3 x i64> %shift_amt, splat (i64 32)
+  %shl = shl <3 x i64> %arg0, %or
+  ret <3 x i64> %shl
+}
+
+define <4 x i64> @shl_v4_or32_sgpr(<4 x i64> inreg %arg0, <4 x i64> inreg %shift_amt) {
+; CHECK-LABEL: shl_v4_or32_sgpr:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    s_lshl_b32 s4, s16, s24
+; CHECK-NEXT:    s_lshl_b32 s5, s18, s26
+; CHECK-NEXT:    s_lshl_b32 s6, s20, s28
+; CHECK-NEXT:    v_lshlrev_b32_e64 v7, v0, s22
+; CHECK-NEXT:    v_mov_b32_e32 v0, 0
+; CHECK-NEXT:    v_mov_b32_e32 v1, s4
+; CHECK-NEXT:    v_mov_b32_e32 v2, 0
+; CHECK-NEXT:    v_mov_b32_e32 v3, s5
+; CHECK-NEXT:    v_mov_b32_e32 v4, 0
+; CHECK-NEXT:    v_mov_b32_e32 v5, s6
+; CHECK-NEXT:    v_mov_b32_e32 v6, 0
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %or = or <4 x i64> %shift_amt, splat (i64 32)
+  %shl = shl <4 x i64> %arg0, %or
+  ret <4 x i64> %shl
+}
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; Test range from max/min
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+; FIXME: This case should be reduced too, but computeKnownBits() cannot
+;        determine the range.  Match current results for now.
+
+define i64 @shl_maxmin(i64 %arg0, i64 noundef %arg1) {
+; CHECK-LABEL: shl_maxmin:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[2:3]
+; CHECK-NEXT:    v_cndmask_b32_e32 v3, 0, v3, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v2, 32, v2, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[2:3]
+; CHECK-NEXT:    v_cndmask_b32_e32 v2, 63, v2, vcc
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v2, v[0:1]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %max = call i64 @llvm.umax.i64(i64 %arg1, i64 32)
+  %min = call i64 @llvm.umin.i64(i64 %max,  i64 63)
+  %shl = shl i64 %arg0, %min
+  ret i64 %shl
+}
+
+define <2 x i64> @shl_v2_maxmin(<2 x i64> %arg0, <2 x i64> noundef %arg1) {
+; CHECK-LABEL: shl_v2_maxmin:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[4:5]
+; CHECK-NEXT:    v_cndmask_b32_e32 v5, 0, v5, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v4, 32, v4, vcc
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[6:7]
+; CHECK-NEXT:    v_cndmask_b32_e32 v7, 0, v7, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v6, 32, v6, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[6:7]
+; CHECK-NEXT:    v_cndmask_b32_e32 v6, 63, v6, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[4:5]
+; CHECK-NEXT:    v_lshlrev_b64 v[2:3], v6, v[2:3]
+; CHECK-NEXT:    v_cndmask_b32_e32 v4, 63, v4, vcc
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v4, v[0:1]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %max = call <2 x i64> @llvm.umax.i64(<2 x i64> %arg1, <2 x i64> splat (i64 32))
+  %min = call <2 x i64> @llvm.umin.i64(<2 x i64> %max,  <2 x i64> splat (i64 63))
+  %shl = shl <2 x i64> %arg0, %min
+  ret <2 x i64> %shl
+}
+
+define <3 x i64> @shl_v3_maxmin(<3 x i64> %arg0, <3 x i64> noundef %arg1) {
+; CHECK-LABEL: shl_v3_maxmin:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[6:7]
+; CHECK-NEXT:    v_cndmask_b32_e32 v7, 0, v7, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v6, 32, v6, vcc
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[8:9]
+; CHECK-NEXT:    v_cndmask_b32_e32 v9, 0, v9, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v8, 32, v8, vcc
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[10:11]
+; CHECK-NEXT:    v_cndmask_b32_e32 v11, 0, v11, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v10, 32, v10, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[10:11]
+; CHECK-NEXT:    v_cndmask_b32_e32 v10, 63, v10, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[8:9]
+; CHECK-NEXT:    v_lshlrev_b64 v[4:5], v10, v[4:5]
+; CHECK-NEXT:    v_cndmask_b32_e32 v8, 63, v8, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[6:7]
+; CHECK-NEXT:    v_lshlrev_b64 v[2:3], v8, v[2:3]
+; CHECK-NEXT:    v_cndmask_b32_e32 v6, 63, v6, vcc
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v6, v[0:1]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %max = call <3 x i64> @llvm.umax.i64(<3 x i64> %arg1, <3 x i64> splat (i64 32))
+  %min = call <3 x i64> @llvm.umin.i64(<3 x i64> %max,  <3 x i64> splat (i64 63))
+  %shl = shl <3 x i64> %arg0, %min
+  ret <3 x i64> %shl
+}
+
+define <4 x i64> @shl_v4_maxmin(<4 x i64> %arg0, <4 x i64> noundef %arg1) {
+; CHECK-LABEL: shl_v4_maxmin:
+; CHECK:       ; %bb.0:
+; CHECK-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[8:9]
+; CHECK-NEXT:    v_cndmask_b32_e32 v9, 0, v9, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v8, 32, v8, vcc
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[10:11]
+; CHECK-NEXT:    v_cndmask_b32_e32 v11, 0, v11, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v10, 32, v10, vcc
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[12:13]
+; CHECK-NEXT:    v_cndmask_b32_e32 v13, 0, v13, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v12, 32, v12, vcc
+; CHECK-NEXT:    v_cmp_lt_u64_e32 vcc, 32, v[14:15]
+; CHECK-NEXT:    v_cndmask_b32_e32 v15, 0, v15, vcc
+; CHECK-NEXT:    v_cndmask_b32_e32 v14, 32, v14, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[14:15]
+; CHECK-NEXT:    v_cndmask_b32_e32 v14, 63, v14, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[12:13]
+; CHECK-NEXT:    v_lshlrev_b64 v[6:7], v14, v[6:7]
+; CHECK-NEXT:    v_cndmask_b32_e32 v12, 63, v12, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[10:11]
+; CHECK-NEXT:    v_lshlrev_b64 v[4:5], v12, v[4:5]
+; CHECK-NEXT:    v_cndmask_b32_e32 v10, 63, v10, vcc
+; CHECK-NEXT:    v_cmp_gt_u64_e32 vcc, 63, v[8:9]
+; CHECK-NEXT:    v_lshlrev_b64 v[2:3], v10, v[2:3]
+; CHECK-NEXT:    v_cndmask_b32_e32 v8, 63, v8, vcc
+; CHECK-NEXT:    v_lshlrev_b64 v[0:1], v8, v[0:1]
+; CHECK-NEXT:    s_setpc_b64 s[30:31]
+  %max = call <4 x i64> @llvm.umax.i64(<4 x i64> %arg1, <4 x i64> splat (i64 32))
+  %min = call <4 x i64> @llvm.umin.i64(<4 x i64> %max,  <4 x i64> splat (i64 63))
+  %shl = shl <4 x i64> %arg0, %min
+  ret <4 x i64> %shl
+}

diff  --git a/llvm/test/CodeGen/AMDGPU/shl64_reduce_flags.ll b/llvm/test/CodeGen/AMDGPU/shl64_reduce_flags.ll
new file mode 100644
index 0000000000000..7c75303c3463f
--- /dev/null
+++ b/llvm/test/CodeGen/AMDGPU/shl64_reduce_flags.ll
@@ -0,0 +1,99 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -stop-after=finalize-isel -o - %s | FileCheck %s
+
+;; Test that reduction of:
+;;
+;;   DST = shl i64 X, Y
+;;
+;; where Y is in the range [63-32] to:
+;;
+;;   DST = [0, shl i32 X, (Y & 0x1F)]
+;;
+;; preserves flags
+
+define i64 @shl_nsw(i64 %arg0, i64 %shift_amt) {
+  ; CHECK-LABEL: name: shl_nsw
+  ; CHECK: bb.0 (%ir-block.0):
+  ; CHECK-NEXT:   liveins: $vgpr0, $vgpr2
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr2
+  ; CHECK-NEXT:   [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr0
+  ; CHECK-NEXT:   [[DEF:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF1:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF2:%[0-9]+]]:sgpr_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[COPY2:%[0-9]+]]:vgpr_32 = COPY [[DEF]]
+  ; CHECK-NEXT:   [[REG_SEQUENCE:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[COPY1]], %subreg.sub0, killed [[COPY2]], %subreg.sub1
+  ; CHECK-NEXT:   [[DEF3:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF4:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF5:%[0-9]+]]:sgpr_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[COPY3:%[0-9]+]]:vgpr_32 = COPY [[DEF3]]
+  ; CHECK-NEXT:   [[REG_SEQUENCE1:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[COPY]], %subreg.sub0, killed [[COPY3]], %subreg.sub1
+  ; CHECK-NEXT:   [[COPY4:%[0-9]+]]:vgpr_32 = COPY [[REG_SEQUENCE1]].sub0
+  ; CHECK-NEXT:   [[COPY5:%[0-9]+]]:vgpr_32 = COPY [[REG_SEQUENCE]].sub0
+  ; CHECK-NEXT:   [[V_LSHLREV_B32_e64_:%[0-9]+]]:vgpr_32 = nsw V_LSHLREV_B32_e64 killed [[COPY4]], killed [[COPY5]], implicit $exec
+  ; CHECK-NEXT:   [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
+  ; CHECK-NEXT:   $vgpr0 = COPY [[V_MOV_B32_e32_]]
+  ; CHECK-NEXT:   $vgpr1 = COPY [[V_LSHLREV_B32_e64_]]
+  ; CHECK-NEXT:   SI_RETURN implicit $vgpr0, implicit $vgpr1
+  %or = or i64 %shift_amt, 32
+  %shl = shl nsw i64 %arg0, %or
+  ret i64 %shl
+}
+
+define i64 @shl_nuw(i64 %arg0, i64 %shift_amt) {
+  ; CHECK-LABEL: name: shl_nuw
+  ; CHECK: bb.0 (%ir-block.0):
+  ; CHECK-NEXT:   liveins: $vgpr0, $vgpr2
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr2
+  ; CHECK-NEXT:   [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr0
+  ; CHECK-NEXT:   [[DEF:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF1:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF2:%[0-9]+]]:sgpr_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[COPY2:%[0-9]+]]:vgpr_32 = COPY [[DEF]]
+  ; CHECK-NEXT:   [[REG_SEQUENCE:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[COPY1]], %subreg.sub0, killed [[COPY2]], %subreg.sub1
+  ; CHECK-NEXT:   [[DEF3:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF4:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF5:%[0-9]+]]:sgpr_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[COPY3:%[0-9]+]]:vgpr_32 = COPY [[DEF3]]
+  ; CHECK-NEXT:   [[REG_SEQUENCE1:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[COPY]], %subreg.sub0, killed [[COPY3]], %subreg.sub1
+  ; CHECK-NEXT:   [[COPY4:%[0-9]+]]:vgpr_32 = COPY [[REG_SEQUENCE1]].sub0
+  ; CHECK-NEXT:   [[COPY5:%[0-9]+]]:vgpr_32 = COPY [[REG_SEQUENCE]].sub0
+  ; CHECK-NEXT:   [[V_LSHLREV_B32_e64_:%[0-9]+]]:vgpr_32 = nuw V_LSHLREV_B32_e64 killed [[COPY4]], killed [[COPY5]], implicit $exec
+  ; CHECK-NEXT:   [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
+  ; CHECK-NEXT:   $vgpr0 = COPY [[V_MOV_B32_e32_]]
+  ; CHECK-NEXT:   $vgpr1 = COPY [[V_LSHLREV_B32_e64_]]
+  ; CHECK-NEXT:   SI_RETURN implicit $vgpr0, implicit $vgpr1
+  %or = or i64 %shift_amt, 32
+  %shl = shl nuw i64 %arg0, %or
+  ret i64 %shl
+}
+
+define i64 @shl_nsw_nuw(i64 %arg0, i64 %shift_amt) {
+  ; CHECK-LABEL: name: shl_nsw_nuw
+  ; CHECK: bb.0 (%ir-block.0):
+  ; CHECK-NEXT:   liveins: $vgpr0, $vgpr2
+  ; CHECK-NEXT: {{  $}}
+  ; CHECK-NEXT:   [[COPY:%[0-9]+]]:vgpr_32 = COPY $vgpr2
+  ; CHECK-NEXT:   [[COPY1:%[0-9]+]]:vgpr_32 = COPY $vgpr0
+  ; CHECK-NEXT:   [[DEF:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF1:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF2:%[0-9]+]]:sgpr_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[COPY2:%[0-9]+]]:vgpr_32 = COPY [[DEF]]
+  ; CHECK-NEXT:   [[REG_SEQUENCE:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[COPY1]], %subreg.sub0, killed [[COPY2]], %subreg.sub1
+  ; CHECK-NEXT:   [[DEF3:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF4:%[0-9]+]]:sreg_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[DEF5:%[0-9]+]]:sgpr_32 = IMPLICIT_DEF
+  ; CHECK-NEXT:   [[COPY3:%[0-9]+]]:vgpr_32 = COPY [[DEF3]]
+  ; CHECK-NEXT:   [[REG_SEQUENCE1:%[0-9]+]]:vreg_64 = REG_SEQUENCE [[COPY]], %subreg.sub0, killed [[COPY3]], %subreg.sub1
+  ; CHECK-NEXT:   [[COPY4:%[0-9]+]]:vgpr_32 = COPY [[REG_SEQUENCE1]].sub0
+  ; CHECK-NEXT:   [[COPY5:%[0-9]+]]:vgpr_32 = COPY [[REG_SEQUENCE]].sub0
+  ; CHECK-NEXT:   [[V_LSHLREV_B32_e64_:%[0-9]+]]:vgpr_32 = nuw nsw V_LSHLREV_B32_e64 killed [[COPY4]], killed [[COPY5]], implicit $exec
+  ; CHECK-NEXT:   [[V_MOV_B32_e32_:%[0-9]+]]:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
+  ; CHECK-NEXT:   $vgpr0 = COPY [[V_MOV_B32_e32_]]
+  ; CHECK-NEXT:   $vgpr1 = COPY [[V_LSHLREV_B32_e64_]]
+  ; CHECK-NEXT:   SI_RETURN implicit $vgpr0, implicit $vgpr1
+  %or = or i64 %shift_amt, 32
+  %shl = shl nsw nuw i64 %arg0, %or
+  ret i64 %shl
+}


        


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