make allocated macro more reliable

Changes testset to avoid compiler heuristics (copyast) that disables inference.
And changes the allocated macro to rely less on inference to elid allocations for the machinary itself.

base/util.jl

@@ -60,9 +60,6 @@ end
 # total time spend in garbage collection, in nanoseconds
 gc_time_ns() = ccall(:jl_gc_total_hrtime, UInt64, ())
 
-# total number of bytes allocated so far
-gc_bytes() = ccall(:jl_gc_total_bytes, Int64, ())
-
 # print elapsed time, return expression value
 const _mem_units = ["byte", "KiB", "MiB", "GiB", "TiB", "PiB"]
 const _cnt_units = ["", " k", " M", " G", " T", " P"]
@@ -223,21 +220,14 @@ macro elapsed(ex)
     end
 end
 
-# measure bytes allocated without *most* contamination from compilation
-# Note: This reports a different value from the @time macros, because
-# it wraps the call in a function, however, this means that things
-# like:  @allocated y = foo()
-# will not work correctly, because it will set y in the context of
-# the local function made by the macro, not the current function
+# total number of bytes allocated so far
+gc_bytes(b::Ref{Int64}) = ccall(:jl_gc_get_total_bytes, Cvoid, (Ptr{Int64},), b)
+
 """
     @allocated
 
 A macro to evaluate an expression, discarding the resulting value, instead returning the
-total number of bytes allocated during evaluation of the expression. Note: the expression is
-evaluated inside a local function, instead of the current context, in order to eliminate the
-effects of compilation, however, there still may be some allocations due to JIT compilation.
-This also makes the results inconsistent with the `@time` macros, which do not try to adjust
-for the effects of compilation.
+total number of bytes allocated during evaluation of the expression.
 
 See also [`@time`](@ref), [`@timev`](@ref), [`@timed`](@ref),
 and [`@elapsed`](@ref).
@@ -249,15 +239,13 @@ julia> @allocated rand(10^6)
 """
 macro allocated(ex)
     quote
-        let
-            local f
-            function f()
-                b0 = gc_bytes()
-                $(esc(ex))
-                gc_bytes() - b0
-            end
-            f()
-        end
+        while false; end # compiler heuristic: compile this block (alter this if the heuristic changes)
+        local b0 = Ref{Int64}(0)
+        local b1 = Ref{Int64}(0)
+        gc_bytes(b0)
+        $(esc(ex))
+        gc_bytes(b1)
+        b1[] - b0[]
     end
 end
 

src/gc.c

@@ -2625,38 +2625,47 @@ JL_DLLEXPORT int jl_gc_enable(int on)
     }
     return prev;
 }
+
 JL_DLLEXPORT int jl_gc_is_enabled(void)
 {
     jl_ptls_t ptls = jl_get_ptls_states();
     return !ptls->disable_gc;
 }
 
-JL_DLLEXPORT int64_t jl_gc_total_bytes(void)
+JL_DLLEXPORT void jl_gc_get_total_bytes(int64_t *bytes)
 {
     jl_gc_num_t num = gc_num;
     combine_thread_gc_counts(&num);
     // Sync this logic with `base/util.jl:GC_Diff`
-    return (num.total_allocd + num.deferred_alloc + num.allocd);
+    *bytes = (num.total_allocd + num.deferred_alloc + num.allocd);
 }
+
 JL_DLLEXPORT uint64_t jl_gc_total_hrtime(void)
 {
     return gc_num.total_time;
 }
+
 JL_DLLEXPORT jl_gc_num_t jl_gc_num(void)
 {
     jl_gc_num_t num = gc_num;
     combine_thread_gc_counts(&num);
     return num;
 }
 
+// TODO: these were supposed to be thread local
 JL_DLLEXPORT int64_t jl_gc_diff_total_bytes(void)
 {
     int64_t oldtb = last_gc_total_bytes;
-    int64_t newtb = jl_gc_total_bytes();
+    int64_t newtb;
+    jl_gc_get_total_bytes(&newtb);
     last_gc_total_bytes = newtb;
     return newtb - oldtb;
 }
-void jl_gc_sync_total_bytes(void) {last_gc_total_bytes = jl_gc_total_bytes();}
+
+void jl_gc_sync_total_bytes(void)
+{
+    jl_gc_get_total_bytes(&last_gc_total_bytes);
+}
 
 static void jl_gc_premark(jl_ptls_t ptls2)
 {

src/julia.h

@@ -749,9 +749,6 @@ extern void JL_GC_POP() JL_NOTSAFEPOINT;
 
 JL_DLLEXPORT int jl_gc_enable(int on);
 JL_DLLEXPORT int jl_gc_is_enabled(void);
-JL_DLLEXPORT int64_t jl_gc_total_bytes(void);
-JL_DLLEXPORT uint64_t jl_gc_total_hrtime(void);
-JL_DLLEXPORT int64_t jl_gc_diff_total_bytes(void);
 
 typedef enum {
     JL_GC_AUTO = 0,         // use heuristics to determine the collection type

src/julia_internal.h

@@ -319,6 +319,7 @@ JL_DLLEXPORT void *jl_gc_counted_malloc(size_t sz);
 
 JL_DLLEXPORT void JL_NORETURN jl_throw_out_of_memory_error(void);
 
+JL_DLLEXPORT int64_t jl_gc_diff_total_bytes(void);
 void jl_gc_sync_total_bytes(void);
 void jl_gc_track_malloced_array(jl_ptls_t ptls, jl_array_t *a) JL_NOTSAFEPOINT;
 void jl_gc_count_allocd(size_t sz) JL_NOTSAFEPOINT;

stdlib/Test/src/Test.jl

@@ -1109,7 +1109,7 @@ function testset_beginend(args, tests, source)
             err isa InterruptException && rethrow()
             # something in the test block threw an error. Count that as an
             # error in this test set
-            record(ts, Error(:nontest_error, :(), err, Base.catch_stack(), $(QuoteNode(source))))
+            record(ts, Error(:nontest_error, Expr(:tuple), err, Base.catch_stack(), $(QuoteNode(source))))
         finally
             copy!(RNG, oldrng)
         end
@@ -1182,7 +1182,7 @@ function testset_forloop(args, testloop, source)
             err isa InterruptException && rethrow()
             # Something in the test block threw an error. Count that as an
             # error in this test set
-            record(ts, Error(:nontest_error, :(), err, Base.catch_stack(), $(QuoteNode(source))))
+            record(ts, Error(:nontest_error, Expr(:tuple), err, Base.catch_stack(), $(QuoteNode(source))))
         end
     end
     quote

test/core.jl

@@ -5019,13 +5019,15 @@ end
 # when calculating total allocation size.
 @noinline function f17255(n)
     GC.enable(false)
-    b0 = Base.gc_bytes()
+    b0 = Ref{Int64}(0)
+    b1 = Ref{Int64}(0)
+    Base.gc_bytes(b0)
     local a
     for i in 1:n
         a, t, allocd = @timed [Ref(1) for i in 1:1000]
         @test allocd > 0
-        b1 = Base.gc_bytes()
-        if b1 < b0
+        Base.gc_bytes(b1)
+        if b1[] < b0[]
             return false, a
         end
     end

test/offsetarray.jl

@@ -533,15 +533,15 @@ end
     B = OffsetArray(reshape(1:24, 4, 3, 2), -5, 6, -7)
     for R in (fill(0, -4:-1), fill(0, -4:-1, 7:7), fill(0, -4:-1, 7:7, -6:-6))
         @test @inferred(maximum!(R, B)) == reshape(maximum(B, dims=(2,3)), axes(R)) == reshape(21:24, axes(R))
-        @test @allocated(maximum!(R, B)) <= 400
+        @test @allocated(maximum!(R, B)) <= 800
         @test @inferred(minimum!(R, B)) == reshape(minimum(B, dims=(2,3)), axes(R)) == reshape(1:4, axes(R))
-        @test @allocated(minimum!(R, B)) <= 400
+        @test @allocated(minimum!(R, B)) <= 800
     end
     for R in (fill(0, -4:-4, 7:9), fill(0, -4:-4, 7:9, -6:-6))
         @test @inferred(maximum!(R, B)) == reshape(maximum(B, dims=(1,3)), axes(R)) == reshape(16:4:24, axes(R))
-        @test @allocated(maximum!(R, B)) <= 400
+        @test @allocated(maximum!(R, B)) <= 800
         @test @inferred(minimum!(R, B)) == reshape(minimum(B, dims=(1,3)), axes(R)) == reshape(1:4:9, axes(R))
-        @test @allocated(minimum!(R, B)) <= 400
+        @test @allocated(minimum!(R, B)) <= 800
     end
     @test_throws DimensionMismatch maximum!(fill(0, -4:-1, 7:7, -6:-6, 1:1), B)
     @test_throws DimensionMismatch minimum!(fill(0, -4:-1, 7:7, -6:-6, 1:1), B)

test/ranges.jl

@@ -1490,8 +1490,6 @@ end
 end
 
 @testset "allocation of TwicePrecision call" begin
-    0:286.493442:360
-    0:286:360
     @test @allocated(0:286.493442:360) == 0
     @test @allocated(0:286:360) == 0
 end

test/syntax.jl

@@ -1845,8 +1845,7 @@ end
 @testset "closure conversion in testsets" begin
     p = (2, 3, 4)
     @test p == (2, 3, 4)
-    identity(p)
-    allocs = @allocated identity(p)
+    allocs = (() -> @allocated identity(p))()
     @test allocs == 0
 end