From 17dea772579f5c7197ee33b3ad84bcf7249fd48b Mon Sep 17 00:00:00 2001
From: Jameson Nash <vtjnash@gmail.com>
Date: Wed, 1 Jun 2016 00:02:46 -0400
Subject: [PATCH] remove the ability for codegen to compute specialized call
 sites

fix #16201
---
 src/codegen.cpp   | 59 +----------------------------------------------
 test/inference.jl | 12 ++++++----
 2 files changed, 9 insertions(+), 62 deletions(-)

diff --git a/src/codegen.cpp b/src/codegen.cpp
index f7db178aea654a..8cdf3a371e7764 100644
--- a/src/codegen.cpp
+++ b/src/codegen.cpp
@@ -2061,23 +2061,6 @@ static Value *emit_f_is(const jl_cgval_t &arg1, const jl_cgval_t &arg2, jl_codec
 #endif
 }
 
-static jl_svec_t *call_arg_types(jl_value_t **args, size_t n, jl_codectx_t *ctx)
-{
-    jl_svec_t *t = jl_alloc_svec(n);
-    JL_GC_PUSH1(&t);
-    size_t i;
-    for(i=0; i < n; i++) {
-        jl_value_t *ty = expr_type(args[i], ctx);
-        if (!jl_is_leaf_type(ty)) {
-            t = NULL;
-            break;
-        }
-        jl_svecset(t, i, ty);
-    }
-    JL_GC_POP();
-    return t;
-}
-
 static bool emit_builtin_call(jl_cgval_t *ret, jl_value_t *f, jl_value_t **args, size_t nargs,
                               jl_codectx_t *ctx, jl_value_t *expr)
 // returns true if the call has been handled
@@ -2731,11 +2714,10 @@ static jl_cgval_t emit_call(jl_expr_t *ex, jl_codectx_t *ctx)
     size_t nargs = arglen - 1;
     assert(arglen >= 1);
     Value *theFptr = NULL;
-    jl_value_t *aty = NULL;
     jl_cgval_t result;
 
     jl_function_t *f = (jl_function_t*)static_eval(args[0], ctx, true);
-    JL_GC_PUSH2(&f, &aty);
+    JL_GC_PUSH1(&f);
     if (f != NULL) {
         // function is a compile-time constant
         if (jl_typeis(f, jl_intrinsic_type)) {
@@ -2765,45 +2747,6 @@ static jl_cgval_t emit_call(jl_expr_t *ex, jl_codectx_t *ctx)
         }
     }
 
-    if (ctx->linfo->inferred) {
-        aty = (jl_value_t*)call_arg_types(args, arglen, ctx);
-        // attempt compile-time specialization for inferred types
-        if (aty != NULL) {
-            aty = (jl_value_t*)jl_apply_tuple_type((jl_svec_t*)aty);
-            /*if (trace) {
-                  jl_printf(JL_STDOUT, "call %s%s\n",
-                  jl_sprint(args[0]),
-                  jl_sprint((jl_value_t*)aty));
-              }*/
-            jl_lambda_info_t *li = jl_get_specialization1((jl_tupletype_t*)aty);
-            if (li != NULL && !li->inInference) {
-                jl_compile_linfo(li);
-                assert(li->functionObjectsDecls.functionObject != NULL);
-                theFptr = (Value*)li->functionObjectsDecls.functionObject;
-                jl_cgval_t fval;
-                if (f != NULL) {
-                    // TODO jb/functions: avoid making too many roots here
-                    if (!jl_is_globalref(args[0]) && !jl_is_symbol(args[0]) &&
-                        !jl_is_leaf_type(f)) {
-                        if (ctx->linfo->def)
-                            jl_add_linfo_root(ctx->linfo, f);
-                        else // for toplevel thunks, just write the value back to the AST to root it
-                            jl_array_ptr_set(ex->args, 0, f);
-                    }
-                    fval = mark_julia_const((jl_value_t*)f);
-                }
-                else {
-                    fval = emit_expr(args[0], ctx);
-                }
-                if (ctx->linfo->def) // root this li in case it gets deleted from the cache in `f`
-                    jl_add_linfo_root(ctx->linfo, (jl_value_t*)li);
-                result = emit_call_function_object(li, fval, theFptr, args, nargs, expr, ctx);
-                JL_GC_POP();
-                return result;
-            }
-        }
-    }
-
     // emit function and arguments
     nargs++; // add function to nargs count
     jl_cgval_t *anArg = (jl_cgval_t*)alloca(sizeof(jl_cgval_t) * nargs);
diff --git a/test/inference.jl b/test/inference.jl
index d15ee68205f4b5..05216b4786c83e 100644
--- a/test/inference.jl
+++ b/test/inference.jl
@@ -5,14 +5,14 @@
 # issue 9770
 @noinline x9770() = false
 function f9770(x)
-    if x9770()
+    return if x9770()
         g9770(:a, :foo)
     else
         x
     end
 end
 function g9770(x,y)
-   if isa(y, Symbol)
+   return if isa(y, Symbol)
        f9770(x)
    else
        g9770(:a, :foo)
@@ -58,7 +58,7 @@ function g3182(t::DataType)
     # subtype of Type, but we cannot infer the T in Type{T} just
     # by knowing (at compile time) that the argument is a DataType.
     # however the ::Type{T} method should still match at run time.
-    f3182(t)
+    return f3182(t)
 end
 @test g3182(Complex) == 0
 
@@ -107,7 +107,7 @@ barTuple2() = fooTuple{tuple(:y)}()
 # issue #12476
 function f12476(a)
     (k, v) = a
-    v
+    return v
 end
 @inferred f12476(1.0 => 1)
 
@@ -143,14 +143,17 @@ f12826{I<:Integer}(v::Vector{I}) = v[1]
 
 
 # non-terminating inference, issue #14009
+# non-terminating codegen, issue #16201
 type A14009{T}; end
 A14009{T}(a::T) = A14009{T}()
 f14009(a) = rand(Bool) ? f14009(A14009(a)) : a
 code_typed(f14009, (Int,))
+code_llvm(DevNull, f14009, (Int,))
 
 type B14009{T}; end
 g14009(a) = g14009(B14009{a})
 code_typed(g14009, (Type{Int},))
+code_llvm(DevNull, f14009, (Int,))
 
 
 # issue #9232
@@ -164,6 +167,7 @@ result_type9232{T1<:Number,T2<:Number}(::Type{T1}, ::Type{T2}) = arithtype9232(T
 function g10878(x; kw...); end
 invoke_g10878() = invoke(g10878, Tuple{Any}, 1)
 @code_typed invoke_g10878()
+code_llvm(DevNull, invoke_g10878, ())
 
 
 # issue #10930