Index: llvm/lib/Target/AMDGPU/AMDGPUGISel.td
===================================================================
--- llvm/lib/Target/AMDGPU/AMDGPUGISel.td
+++ llvm/lib/Target/AMDGPU/AMDGPUGISel.td
@@ -214,3 +214,6 @@
 
 def gi_bitcast_fpimm_to_i32 : GICustomOperandRenderer<"renderBitcastImm">,
   GISDNodeXFormEquiv<bitcast_fpimm_to_i32>;
+
+def gi_IMMPopCount : GICustomOperandRenderer<"renderPopcntImm">,
+  GISDNodeXFormEquiv<IMMPopCount>;
Index: llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.h
===================================================================
--- llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.h
+++ llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.h
@@ -177,6 +177,9 @@
   void renderBitcastImm(MachineInstrBuilder &MIB,
                         const MachineInstr &MI) const;
 
+  void renderPopcntImm(MachineInstrBuilder &MIB,
+                       const MachineInstr &MI) const;
+
   bool isInlineImmediate16(int64_t Imm) const;
   bool isInlineImmediate32(int64_t Imm) const;
   bool isInlineImmediate64(int64_t Imm) const;
Index: llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp
===================================================================
--- llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp
+++ llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp
@@ -2128,6 +2128,12 @@
   }
 }
 
+void AMDGPUInstructionSelector::renderPopcntImm(MachineInstrBuilder &MIB,
+                                                const MachineInstr &MI) const {
+  assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && "Expected G_CONSTANT");
+  MIB.addImm(MI.getOperand(1).getCImm()->getValue().countPopulation());
+}
+
 bool AMDGPUInstructionSelector::isInlineImmediate16(int64_t Imm) const {
   return AMDGPU::isInlinableLiteral16(Imm, STI.hasInv2PiInlineImm());
 }