Remove the first_right_arg hack for HMod.

src/arm/lithium-codegen-arm.cc

Index: src/arm/lithium-codegen-arm.cc
diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 0d4d805acbed5ab227d64cf2a6fd7c85635ace07..8ace35ce740ff0d0cc00ac3d3eadef048f16d7a8 100644
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -1133,36 +1133,6 @@ void LCodeGen::DoModI(LModI* instr) {
     __ bind(&left_is_not_negative);
     __ and_(result_reg, left_reg, Operand(divisor - 1));
     __ bind(&done);
-
-  } else if (hmod->fixed_right_arg().has_value) {
-    Register left_reg = ToRegister(instr->left());
-    Register right_reg = ToRegister(instr->right());
-    Register result_reg = ToRegister(instr->result());
-
-    int32_t divisor = hmod->fixed_right_arg().value;
-    ASSERT(IsPowerOf2(divisor));
-
-    // Check if our assumption of a fixed right operand still holds.
-    __ cmp(right_reg, Operand(divisor));
-    DeoptimizeIf(ne, instr->environment());
-
-    Label left_is_not_negative, done;
-    if (left->CanBeNegative()) {
-      __ cmp(left_reg, Operand::Zero());
-      __ b(pl, &left_is_not_negative);
-      __ rsb(result_reg, left_reg, Operand::Zero());
-      __ and_(result_reg, result_reg, Operand(divisor - 1));
-      __ rsb(result_reg, result_reg, Operand::Zero(), SetCC);
-      if (hmod->CheckFlag(HValue::kBailoutOnMinusZero)) {
-        DeoptimizeIf(eq, instr->environment());
-      }
-      __ b(&done);
-    }
-
-    __ bind(&left_is_not_negative);
-    __ and_(result_reg, left_reg, Operand(divisor - 1));
-    __ bind(&done);
-
   } else if (CpuFeatures::IsSupported(SUDIV)) {
     CpuFeatureScope scope(masm(), SUDIV);