Index: llvm/lib/Target/M68k/GlSel/M68kLegalizerInfo.cpp
===================================================================
--- llvm/lib/Target/M68k/GlSel/M68kLegalizerInfo.cpp
+++ llvm/lib/Target/M68k/GlSel/M68kLegalizerInfo.cpp
@@ -20,5 +20,14 @@
 using namespace llvm;
 
 M68kLegalizerInfo::M68kLegalizerInfo(const M68kSubtarget &ST) {
+  using namespace TargetOpcode;
+  const LLT s32 = LLT::scalar(32);
+  const LLT p0 = LLT::pointer(0, 32);
+  getActionDefinitionsBuilder(G_LOAD).legalFor({s32});
+  getActionDefinitionsBuilder(G_FRAME_INDEX).legalFor({p0});
+  getActionDefinitionsBuilder(G_ADD).legalFor({s32});
+  getActionDefinitionsBuilder(G_SUB).legalFor({s32});
+  getActionDefinitionsBuilder(G_MUL).legalFor({s32});
+  getActionDefinitionsBuilder(G_UDIV).legalFor({s32});
   getLegacyLegalizerInfo().computeTables();
 }
Index: llvm/test/CodeGen/M68k/GlobalISel/arith.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/M68k/GlobalISel/arith.ll
@@ -0,0 +1,57 @@
+; RUN: llc -mtriple=m68k -global-isel -stop-after=legalizer < %s | FileCheck %s
+
+define i32 @test_add(i32 %x, i32 %y) {
+  ; CHECK-LABEL: name: test_add
+  ; CHECK: bb.1 (%ir-block.0):
+  ; CHECK:   [[G_F_I1:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD1:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I1]](p0)
+  ; CHECK:   [[G_F_I2:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD2:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I2]](p0)
+  ; CHECK:   [[G_ADD1:%[0-9]+]]:_(s32) = G_ADD [[G_LOAD1]], [[G_LOAD2]]
+  ; CHECK:   $d0 = COPY [[G_ADD1]](s32)
+  ; CHECK:   RTS implicit $d0
+  %sum = add i32 %x, %y
+  ret i32 %sum
+}
+
+define i32 @test_sub(i32 %x, i32 %y) {
+  ; CHECK-LABEL: name: test_sub
+  ; CHECK: bb.1 (%ir-block.0):
+  ; CHECK:   [[G_F_I1:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD1:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I1]](p0)
+  ; CHECK:   [[G_F_I2:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD2:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I2]](p0)
+  ; CHECK:   [[G_SUB1:%[0-9]+]]:_(s32) = G_SUB [[G_LOAD1]], [[G_LOAD2]]
+  ; CHECK:   $d0 = COPY [[G_SUB1]](s32)
+  ; CHECK:   RTS implicit $d0
+  %diff = sub i32 %x, %y
+  ret i32 %diff
+}
+
+define i32 @test_mul(i32 %x, i32 %y) {
+  ; CHECK-LABEL: name: test_mul
+  ; CHECK: bb.1 (%ir-block.0):
+  ; CHECK:   [[G_F_I1:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD1:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I1]](p0)
+  ; CHECK:   [[G_F_I2:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD2:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I2]](p0)
+  ; CHECK:   [[G_MUL1:%[0-9]+]]:_(s32) = G_MUL [[G_LOAD1]], [[G_LOAD2]]
+  ; CHECK:   $d0 = COPY [[G_MUL1]](s32)
+  ; CHECK:   RTS implicit $d0
+  %prod = mul i32 %x, %y
+  ret i32 %prod
+}
+
+define i32 @test_udiv(i32 %x, i32 %y) {
+  ; CHECK-LABEL: name: test_udiv
+  ; CHECK: bb.1 (%ir-block.0):
+  ; CHECK:   [[G_F_I1:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD1:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I1]](p0)
+  ; CHECK:   [[G_F_I2:%[0-9]+]]:_(p0) = G_FRAME_INDEX
+  ; CHECK:   [[G_LOAD2:%[0-9]+]]:_(s32) = G_LOAD [[G_F_I2]](p0)
+  ; CHECK:   [[G_DIV1:%[0-9]+]]:_(s32) = G_UDIV [[G_LOAD1]], [[G_LOAD2]]
+  ; CHECK:   $d0 = COPY [[G_DIV1]](s32)
+  ; CHECK:   RTS implicit $d0
+  %div = udiv i32 %x, %y
+  ret i32 %div
+}