Root table items; reverse table/elem edge directions

CONTRIBUTING.md

@@ -10,9 +10,11 @@ out to us in a GitHub issue, or ping `fitzgen` in [`#rust-wasm` on
 
 - [Code of Conduct](#code-of-conduct)
 - [Building and Testing](#building-and-testing)
-  - [Building](#building)
+  - [Building for the Native Target](#building-for-the-native-target)
+  - [Building for the `wasm32-unknown-unknown` Target](#building-for-the-wasm32-unknown-unknown-target)
   - [Testing](#testing)
     - [Authoring New Tests](#authoring-new-tests)
+    - [Updating Test Expectations](#updating-test-expectations)
 - [Automatic Code Formatting](#automatic-code-formatting)
 - [Pull Requests](#pull-requests)
 - [Contributions We Want](#contributions-we-want)
@@ -64,6 +66,12 @@ twiggy/tests
 * The `twiggy/tests/expectations` directory contains the expected output of test
   commands.
 
+#### Updating Test Expectations
+
+To automatically update all test expectations, you can run the tests with the
+`TWIGGY_UPDATE_TEST_EXPECTATIONS=1` environment variable set. Make sure that you
+look at the changes before committing them, and that they match your intentions!
+
 ## Automatic Code Formatting
 
 We use [`rustfmt`](https://github.com/rust-lang-nursery/rustfmt) to enforce a

parser/wasm_parse/mod.rs

@@ -341,7 +341,7 @@ impl<'a> Parse<'a> for elements::TableSection {
             let size = serialized_size(entry.clone())?;
             let mut name = String::with_capacity("table[]".len() + 4);
             write!(&mut name, "table[{}]", i)?;
-            items.add_item(ir::Item::new(id, name, size, ir::Misc::new()));
+            items.add_root(ir::Item::new(id, name, size, ir::Misc::new()));
         }
         Ok(())
     }
@@ -559,7 +559,7 @@ impl<'a> Parse<'a> for elements::ElementSection {
             let elem_id = Id::entry(idx, i);
             if let Some(table_section_idx) = table_section_idx {
                 let entry_id = Id::entry(table_section_idx, elem.index() as usize);
-                items.add_edge(elem_id, entry_id);
+                items.add_edge(entry_id, elem_id);
             }
             for &func_idx in elem.members() {
                 // A table element's initializer function can be an imported

twiggy/tests/all/expectations/diff_wee_alloc_json

@@ -1 +1 @@
-[{"delta_bytes":-1034,"name":"data[3]"},{"delta_bytes":-593,"name":"\"function names\" subsection"},{"delta_bytes":395,"name":"wee_alloc::alloc_first_fit::he2a4ddf96981c0ce"},{"delta_bytes":243,"name":"goodbye"},{"delta_bytes":-225,"name":"wee_alloc::alloc_first_fit::h9a72de3af77ef93f"},{"delta_bytes":-152,"name":"wee_alloc::alloc_with_refill::hb32c1bbce9ebda8e"},{"delta_bytes":145,"name":"<wee_alloc::neighbors::Neighbors<'a, T>>::remove::hc9e5d4284e8233b8"},{"delta_bytes":-136,"name":"<wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::new_cell_for_free_list::h3987e3054b8224e6"},{"delta_bytes":-76,"name":"<wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::new_cell_for_free_list::h8f071b7bce0301ba"},{"delta_bytes":-25,"name":"data[1]"},{"delta_bytes":-25,"name":"data[2]"},{"delta_bytes":15,"name":"hello"},{"delta_bytes":15,"name":"import env::rust_oom"},{"delta_bytes":12,"name":"custom section 'linking'"},{"delta_bytes":-12,"name":"elem[0]"},{"delta_bytes":8,"name":"global[0]"},{"delta_bytes":-8,"name":"type[4]"},{"delta_bytes":-6,"name":"<wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::min_cell_size::hc7cee2a550987099"},{"delta_bytes":6,"name":"alloc::alloc::oom::h45ae3f22a516fb04"},{"delta_bytes":-5,"name":"<wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::min_cell_size::h6f746be886573355"},{"delta_bytes":-21,"name":"... and 13 more."},{"delta_bytes":-1476,"name":"Σ [33 Total Rows]"}]
+[{"delta_bytes":-1034,"name":"data[3]"},{"delta_bytes":-593,"name":"\"function names\" subsection"},{"delta_bytes":395,"name":"wee_alloc::alloc_first_fit::he2a4ddf96981c0ce"},{"delta_bytes":243,"name":"goodbye"},{"delta_bytes":-225,"name":"wee_alloc::alloc_first_fit::h9a72de3af77ef93f"},{"delta_bytes":-152,"name":"wee_alloc::alloc_with_refill::hb32c1bbce9ebda8e"},{"delta_bytes":145,"name":"<wee_alloc::neighbors::Neighbors<'a, T>>::remove::hc9e5d4284e8233b8"},{"delta_bytes":-136,"name":"<wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::new_cell_for_free_list::h3987e3054b8224e6"},{"delta_bytes":-76,"name":"<wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::new_cell_for_free_list::h8f071b7bce0301ba"},{"delta_bytes":-25,"name":"data[1]"},{"delta_bytes":-25,"name":"data[2]"},{"delta_bytes":15,"name":"hello"},{"delta_bytes":15,"name":"import env::rust_oom"},{"delta_bytes":12,"name":"custom section 'linking'"},{"delta_bytes":-12,"name":"elem[0]"},{"delta_bytes":8,"name":"global[0]"},{"delta_bytes":-8,"name":"type[4]"},{"delta_bytes":-6,"name":"<wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::min_cell_size::hc7cee2a550987099"},{"delta_bytes":6,"name":"alloc::alloc::oom::h45ae3f22a516fb04"},{"delta_bytes":-5,"name":"<wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::min_cell_size::h6f746be886573355"},{"delta_bytes":-21,"name":"... and 13 more."},{"delta_bytes":-1476,"name":"Σ [33 Total Rows]"}]

twiggy/tests/all/expectations/diff_wee_alloc_json_top_5

@@ -1 +1 @@
-[{"delta_bytes":-1034,"name":"data[3]"},{"delta_bytes":-593,"name":"\"function names\" subsection"},{"delta_bytes":395,"name":"wee_alloc::alloc_first_fit::he2a4ddf96981c0ce"},{"delta_bytes":243,"name":"goodbye"},{"delta_bytes":-225,"name":"wee_alloc::alloc_first_fit::h9a72de3af77ef93f"},{"delta_bytes":-265,"name":"... and 28 more."},{"delta_bytes":-1476,"name":"Σ [33 Total Rows]"}]
+[{"delta_bytes":-1034,"name":"data[3]"},{"delta_bytes":-593,"name":"\"function names\" subsection"},{"delta_bytes":395,"name":"wee_alloc::alloc_first_fit::he2a4ddf96981c0ce"},{"delta_bytes":243,"name":"goodbye"},{"delta_bytes":-225,"name":"wee_alloc::alloc_first_fit::h9a72de3af77ef93f"},{"delta_bytes":-265,"name":"... and 28 more."},{"delta_bytes":-1476,"name":"Σ [33 Total Rows]"}]

twiggy/tests/all/expectations/dominators_wee_alloc

@@ -1,19 +1,38 @@
  Retained Bytes │ Retained % │ Dominator Tree
-────────────────┼────────────┼────────────────────────────────────────────────────────────────────────
+────────────────┼────────────┼───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
             774 ┊     27.48% ┊ "function names" subsection
-            573 ┊     20.34% ┊ export "hello"
-            565 ┊     20.06% ┊   ⤷ func[8]
-            560 ┊     19.88% ┊       ⤷ hello
-            387 ┊     13.74% ┊           ⤷ func[2]
-            378 ┊     13.42% ┊               ⤷ wee_alloc::alloc_with_refill::hb32c1bbce9ebda8e
-            226 ┊      8.02% ┊                   ⤷ func[3]
-            225 ┊      7.99% ┊                       ⤷ wee_alloc::alloc_first_fit::h9a72de3af77ef93f
-              8 ┊      0.28% ┊               ⤷ type[4]
-              9 ┊      0.32% ┊           ⤷ data[0]
+            387 ┊     13.74% ┊ func[2]
+            378 ┊     13.42% ┊   ⤷ wee_alloc::alloc_with_refill::hb32c1bbce9ebda8e
+            226 ┊      8.02% ┊       ⤷ func[3]
+            225 ┊      7.99% ┊           ⤷ wee_alloc::alloc_first_fit::h9a72de3af77ef93f
+              8 ┊      0.28% ┊   ⤷ type[4]
+            271 ┊      9.62% ┊ table[0]
+            267 ┊      9.48% ┊   ⤷ elem[0]
+            137 ┊      4.86% ┊       ⤷ func[5]
+            136 ┊      4.83% ┊           ⤷ <wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::new_cell_for_free_list::h3987e3054b8224e6
+             77 ┊      2.73% ┊       ⤷ func[0]
+             76 ┊      2.70% ┊           ⤷ <wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::new_cell_for_free_list::h8f071b7bce0301ba
+              8 ┊      0.28% ┊       ⤷ func[10]
+              4 ┊      0.14% ┊           ⤷ __wasm_nullptr
+              3 ┊      0.11% ┊           ⤷ type[2]
+              7 ┊      0.25% ┊       ⤷ func[1]
+              6 ┊      0.21% ┊           ⤷ <wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::min_cell_size::hc7cee2a550987099
+              6 ┊      0.21% ┊       ⤷ type[0]
+              6 ┊      0.21% ┊       ⤷ type[1]
+              6 ┊      0.21% ┊       ⤷ func[7]
+              5 ┊      0.18% ┊           ⤷ <wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::min_cell_size::h6f746be886573355
+              4 ┊      0.14% ┊       ⤷ func[4]
+              3 ┊      0.11% ┊           ⤷ core::ptr::drop_in_place::h8e9fdc2437d43666
+              4 ┊      0.14% ┊       ⤷ func[6]
+              3 ┊      0.11% ┊           ⤷ core::ptr::drop_in_place::h4e5cdfd7b9310648.18
+            177 ┊      6.28% ┊ export "hello"
+            169 ┊      6.00% ┊   ⤷ func[8]
+            164 ┊      5.82% ┊       ⤷ hello
               4 ┊      0.14% ┊       ⤷ type[5]
-             59 ┊      2.09% ┊ export "goodbye"
-             49 ┊      1.74% ┊   ⤷ func[9]
+             55 ┊      1.95% ┊ export "goodbye"
+             45 ┊      1.60% ┊   ⤷ func[9]
              44 ┊      1.56% ┊       ⤷ goodbye
-              4 ┊      0.14% ┊       ⤷ type[3]
              11 ┊      0.39% ┊ export "memory"
               2 ┊      0.07% ┊   ⤷ memory[0]
+              9 ┊      0.32% ┊ data[0]
+              4 ┊      0.14% ┊ type[3]

twiggy/tests/all/expectations/dominators_wee_alloc_csv

@@ -1,19 +1,38 @@
 Id,Name,ShallowSize,ShallowSizePercent,RetainedSize,RetainedSizePercent,ImmediateDominator
-18446744073709551615,<meta root>,0,0,1417,50.30173943911963,18446744073709551615
+18446744073709551615,<meta root>,0,0,1688,59.92190273340433,18446744073709551615
 38654705663,"""function names"" subsection",774,27.47603833865815,774,27.47603833865815,18446744073709551615
-17179869185,"export ""hello""",8,0.2839900603478878,573,20.340788072417464,18446744073709551615
-4294967304,func[8],1,0.03549875754348598,565,20.056798012069578,17179869185
-25769803784,hello,164,5.8217962371317,560,19.879304224352147,4294967304
-4294967298,func[2],1,0.03549875754348598,387,13.738019169329075,25769803784
+4294967298,func[2],1,0.03549875754348598,387,13.738019169329075,18446744073709551615
 25769803778,wee_alloc::alloc_with_refill::hb32c1bbce9ebda8e,152,5.395811146609868,378,13.418530351437699,4294967298
 4294967299,func[3],1,0.03549875754348598,226,8.022719204827832,25769803778
 25769803779,wee_alloc::alloc_first_fit::h9a72de3af77ef93f,225,7.987220447284344,225,7.987220447284344,4294967299
 4,type[4],8,0.2839900603478878,8,0.2839900603478878,4294967298
-30064771072,data[0],9,0.3194888178913738,9,0.3194888178913738,25769803784
+8589934592,table[0],4,0.1419950301739439,271,9.620163294284701,18446744073709551615
+21474836480,elem[0],12,0.42598509052183176,267,9.478168264110757,8589934592
+4294967301,func[5],1,0.03549875754348598,137,4.863329783457579,21474836480
+25769803781,<wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::new_cell_for_free_list::h3987e3054b8224e6,136,4.827831025914093,136,4.827831025914093,4294967301
+4294967296,func[0],1,0.03549875754348598,77,2.7334043308484204,21474836480
+25769803776,<wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::new_cell_for_free_list::h8f071b7bce0301ba,76,2.697905573304934,76,2.697905573304934,4294967296
+4294967306,func[10],1,0.03549875754348598,8,0.2839900603478878,21474836480
+25769803786,__wasm_nullptr,4,0.1419950301739439,4,0.1419950301739439,4294967306
+2,type[2],3,0.10649627263045794,3,0.10649627263045794,4294967306
+4294967297,func[1],1,0.03549875754348598,7,0.24849130280440185,21474836480
+25769803777,<wee_alloc::LargeAllocPolicy as wee_alloc::AllocPolicy>::min_cell_size::hc7cee2a550987099,6,0.21299254526091588,6,0.21299254526091588,4294967297
+0,type[0],6,0.21299254526091588,6,0.21299254526091588,21474836480
+1,type[1],6,0.21299254526091588,6,0.21299254526091588,21474836480
+4294967303,func[7],1,0.03549875754348598,6,0.21299254526091588,21474836480
+25769803783,<wee_alloc::size_classes::SizeClassAllocPolicy<'a> as wee_alloc::AllocPolicy>::min_cell_size::h6f746be886573355,5,0.1774937877174299,5,0.1774937877174299,4294967303
+4294967300,func[4],1,0.03549875754348598,4,0.1419950301739439,21474836480
+25769803780,core::ptr::drop_in_place::h8e9fdc2437d43666,3,0.10649627263045794,3,0.10649627263045794,4294967300
+4294967302,func[6],1,0.03549875754348598,4,0.1419950301739439,21474836480
+25769803782,core::ptr::drop_in_place::h4e5cdfd7b9310648.18,3,0.10649627263045794,3,0.10649627263045794,4294967302
+17179869185,"export ""hello""",8,0.2839900603478878,177,6.283280085197019,18446744073709551615
+4294967304,func[8],1,0.03549875754348598,169,5.999290024849131,17179869185
+25769803784,hello,164,5.8217962371317,164,5.8217962371317,4294967304
 5,type[5],4,0.1419950301739439,4,0.1419950301739439,4294967304
-17179869186,"export ""goodbye""",10,0.3549875754348598,59,2.0944266950656725,18446744073709551615
-4294967305,func[9],1,0.03549875754348598,49,1.7394391196308128,17179869186
+17179869186,"export ""goodbye""",10,0.3549875754348598,55,1.9524316648917288,18446744073709551615
+4294967305,func[9],1,0.03549875754348598,45,1.5974440894568689,17179869186
 25769803785,goodbye,44,1.5619453319133831,44,1.5619453319133831,4294967305
-3,type[3],4,0.1419950301739439,4,0.1419950301739439,4294967305
 17179869184,"export ""memory""",9,0.3194888178913738,11,0.3904863329783458,18446744073709551615
 12884901888,memory[0],2,0.07099751508697195,2,0.07099751508697195,17179869184
+30064771072,data[0],9,0.3194888178913738,9,0.3194888178913738,18446744073709551615
+3,type[3],4,0.1419950301739439,4,0.1419950301739439,18446744073709551615