2 files changed, 10 insertions, 3 deletions
diff --git a/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp b/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp
index bd46144..cde2c8d 100644
--- a/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp
+++ b/backend/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp
@@ -405,7 +405,6 @@ public:
     case GenericOpcode::G_DEBUGTRAP:
     case GenericOpcode::G_UBSANTRAP:
     case GenericOpcode::G_PHI:
-    case GenericOpcode::G_IMPLICIT_DEF:
       return {};
     default:
       return makeUnexpected(ErrorCode::Unsupported,
@@ -493,8 +492,6 @@ public:
       return selectTrap(Instruction);
     case GenericOpcode::G_PHI:
       return Instruction.setOpcode(opcode(GenericOpcode::PHI));
-    case GenericOpcode::G_IMPLICIT_DEF:
-      return Instruction.setOpcode(opcode(GenericOpcode::IMPLICIT_DEF));
     case GenericOpcode::COPY:
     case GenericOpcode::IMPLICIT_DEF:
     case GenericOpcode::PHI:
diff --git a/backend/lib/Target/RISCV/RISCVGISelInteger.rccdesc b/backend/lib/Target/RISCV/RISCVGISelInteger.rccdesc
index 1667f66..f40e5d4 100644
--- a/backend/lib/Target/RISCV/RISCVGISelInteger.rccdesc
+++ b/backend/lib/Target/RISCV/RISCVGISelInteger.rccdesc
@@ -1,5 +1,15 @@
 selection_rules:
   -
+    id: select_g_implicit_def
+    priority: 100
+    match:
+      opcode: G_IMPLICIT_DEF
+    apply:
+      instructions:
+        - opcode: IMPLICIT_DEF
+          root: true
+          operands: [{ operand: 0 }]
+  -
     id: select_g_sext_s64_s32
     priority: 500
     match: