Sema: generic function instantiation inherits parent's branch quota

Closes #12624

src/Sema.zig

@@ -6713,6 +6713,8 @@ fn instantiateGenericCall(
             .comptime_args_fn_inst = module_fn.zir_body_inst,
             .preallocated_new_func = new_module_func,
             .is_generic_instantiation = true,
+            .branch_quota = sema.branch_quota,
+            .branch_count = sema.branch_count,
         };
         defer child_sema.deinit();
 

test/cases/compile_errors/generic_funciton_instantiation_inherits_parent_branch_quota.zig

@@ -0,0 +1,30 @@
+pub export fn entry1() void {
+    @setEvalBranchQuota(1001);
+    // Return type evaluation should inherit both the
+    // parent's branch quota and count meaning
+    // at least 2002 backwards branches are required.
+    comptime var i = 0;
+    inline while (i < 1000) : (i += 1) {}
+    _ = simple(10);
+}
+pub export fn entry2() void {
+    @setEvalBranchQuota(2001);
+    comptime var i = 0;
+    inline while (i < 1000) : (i += 1) {}
+    _ = simple(10);
+}
+fn simple(comptime n: usize) Type(n) {
+    return n;
+}
+fn Type(comptime n: usize) type {
+    if (n <= 1) return usize;
+    return Type(n - 1);
+}
+
+// error
+// backend=stage2
+// target=native
+//
+// :21:16: error: evaluation exceeded 1001 backwards branches
+// :21:16: note: use @setEvalBranchQuota() to raise the branch limit from 1001
+// :16:34: note: called from here