Fix a scenario in xlsynth function_zoo.x which fails with TIv2.

PiperOrigin-RevId: 805635892

Author: richmckeever

xls/dslx/bytecode/bytecode_emitter.cc

@@ -753,6 +753,14 @@ absl::Status BytecodeEmitter::HandleBuiltinBitCount(const Invocation* node) {
   return absl::OkStatus();
 }
 
+absl::Status BytecodeEmitter::HandleBuiltinArraySize(const Invocation* node) {
+  XLS_ASSIGN_OR_RETURN(InterpValue default_or_override_interp_value,
+                       type_info_->GetConstExpr(node));
+  bytecode_.push_back(Bytecode(node->span(), Bytecode::Op::kLiteral,
+                               default_or_override_interp_value));
+  return absl::OkStatus();
+}
+
 absl::Status BytecodeEmitter::HandleBuiltinElementCount(
     const Invocation* node) {
   VLOG(5) << "BytecodeEmitter::HandleInvocation - ElementCount @ "
@@ -1107,6 +1115,9 @@ absl::Status BytecodeEmitter::HandleInvocation(const Invocation* node) {
       name_ref != nullptr && name_ref->IsBuiltin()) {
     VLOG(10) << "HandleInvocation; builtin name_ref: " << name_ref->ToString();
 
+    if (name_ref->identifier() == "array_size") {
+      return HandleBuiltinArraySize(node);
+    }
     if (name_ref->identifier() == "bit_count") {
       return HandleBuiltinBitCount(node);
     }

xls/dslx/bytecode/bytecode_emitter.h

@@ -151,6 +151,7 @@ class BytecodeEmitter : public ExprVisitor {
   absl::Status HandleXlsTuple(const XlsTuple* node) override;
 
   // keep-sorted start
+  absl::Status HandleBuiltinArraySize(const Invocation* node);
   absl::Status HandleBuiltinBitCount(const Invocation* node);
   absl::Status HandleBuiltinCheckedCast(const Invocation* node);
   absl::Status HandleBuiltinConfiguredValueOr(const Invocation* node);

xls/dslx/type_system_v2/typecheck_module_v2_test.cc

@@ -9010,5 +9010,22 @@ fn main() -> u32 {
   EXPECT_EQ(result.tm.warnings.warnings().size(), 0);
 }
 
+TEST(TypecheckV2Test, ParametricArraySizeInRange) {
+  EXPECT_THAT(
+      R"(
+fn sum_elements<N: u32>(elements: u32[N]) -> u32 {
+    let result: u32 = for (i, accum) in u32:0..array_size(elements) {
+        accum + elements[i]
+    }(u32:0);
+    result
+}
+
+pub fn sum_elements_2(elements: u32[2]) -> u32 {
+    sum_elements(elements)
+}
+)",
+      TypecheckSucceeds(HasNodeWithType("sum_elements(elements)", "uN[32]")));
+}
+
 }  // namespace
 }  // namespace xls::dslx