handle debug info (#16)

CHANGELOG.md

@@ -16,6 +16,10 @@ The interface provided to smart contracts will adhere to semver with one excepti
 major version bumps will be backwards compatible with regard to already deployed contracts.
 In other words: Upgrading this pallet will not break pre-existing contracts.
 
+## [v0.1.2] 2022-06-06
+- Adjust debug information (if already parsed) when injecting gas metering
+[#16](https://github.com/paritytech/wasm-instrument/pull/16)
+
 ## [v0.1.1] 2022-01-18
 
 ### Fixed

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "wasm-instrument"
-version = "0.1.1"
+version = "0.1.2"
 edition = "2021"
 rust-version = "1.56.1"
 authors = ["Parity Technologies <admin@parity.io>"]
@@ -20,7 +20,7 @@ lto = "fat"
 codegen-units = 1
 
 [dependencies]
-parity-wasm = { version = "0.42", default-features = false }
+parity-wasm = { version = "0.45", default-features = false }
 
 [dev-dependencies]
 binaryen = "0.12"

src/gas_metering/mod.rs

@@ -11,7 +11,7 @@ use alloc::{vec, vec::Vec};
 use core::{cmp::min, mem, num::NonZeroU32};
 use parity_wasm::{
 	builder,
-	elements::{self, Instruction, ValueType},
+	elements::{self, IndexMap, Instruction, ValueType},
 };
 
 /// An interface that describes instruction costs.
@@ -129,7 +129,8 @@ impl Rules for ConstantCostRules {
 ///
 /// The above transformations are performed for every function body defined in the module. This
 /// function also rewrites all function indices references by code, table elements, etc., since
-/// the addition of an imported functions changes the indices of module-defined functions.
+/// the addition of an imported functions changes the indices of module-defined functions. If the
+/// the module has a NameSection, added by calling `parse_names`, the indices will also be updated.
 ///
 /// This routine runs in time linear in the size of the input module.
 ///
@@ -212,6 +213,17 @@ pub fn inject<R: Rules>(
 				if *start_idx >= gas_func {
 					*start_idx += 1
 				},
+			elements::Section::Name(s) =>
+				for functions in s.functions_mut() {
+					*functions.names_mut() =
+						IndexMap::from_iter(functions.names().iter().map(|(mut idx, name)| {
+							if idx >= gas_func {
+								idx += 1;
+							}
+
+							(idx, name.clone())
+						}));
+				},
 			_ => {},
 		}
 	}

tests/diff.rs

@@ -1,3 +1,4 @@
+use parity_wasm::elements::Module;
 use std::{
 	fs,
 	io::{self, Read, Write},
@@ -101,8 +102,10 @@ mod gas {
 				run_diff_test("gas", concat!(stringify!($name), ".wat"), |input| {
 					let rules = instrument::gas_metering::ConstantCostRules::default();
 
-					let module =
+					let module: Module =
 						elements::deserialize_buffer(input).expect("Failed to deserialize");
+					let module = module.parse_names().expect("Failed to parse names");
+
 					let instrumented = instrument::gas_metering::inject(module, &rules, "env")
 						.expect("Failed to instrument with gas metering");
 					elements::serialize(instrumented).expect("Failed to serialize")

tests/expectations/gas/branch.wat

@@ -1,11 +1,11 @@
 (module
   (type (;0;) (func (result i32)))
   (type (;1;) (func (param i32)))
-  (import "env" "gas" (func $fibonacci_with_break (type 1)))
+  (import "env" "gas" (func (;0;) (type 1)))
-  (func (;1;) (type 0) (result i32)
+  (func $fibonacci_with_break (;1;) (type 0) (result i32)
     (local i32 i32)
     i32.const 13
-    call $fibonacci_with_break
+    call 0
     block  ;; label = @1
       i32.const 0
       local.set 0
@@ -19,7 +19,7 @@
       i32.const 1
       br_if 0 (;@1;)
       i32.const 5
-      call $fibonacci_with_break
+      call 0
       local.get 0
       local.get 1
       local.tee 0

tests/expectations/gas/call.wat

@@ -1,20 +1,20 @@
 (module
   (type (;0;) (func (param i32 i32) (result i32)))
   (type (;1;) (func (param i32)))
-  (import "env" "gas" (func $add_locals (type 1)))
+  (import "env" "gas" (func (;0;) (type 1)))
-  (func $add (type 0) (param $x i32) (param $y i32) (result i32)
+  (func $add_locals (;1;) (type 0) (param $x i32) (param $y i32) (result i32)
     (local i32)
     i32.const 5
-    call $add_locals
+    call 0
     local.get $x
     local.get $y
-    call 2
+    call $add
     local.set 2
     local.get 2
   )
-  (func (;2;) (type 0) (param i32 i32) (result i32)
+  (func $add (;2;) (type 0) (param i32 i32) (result i32)
     i32.const 3
-    call $add_locals
+    call 0
     local.get 0
     local.get 1
     i32.add

tests/expectations/gas/start.wat

@@ -2,12 +2,12 @@
   (type (;0;) (func (param i32 i32)))
   (type (;1;) (func))
   (type (;2;) (func (param i32)))
-  (import "env" "ext_return" (func $ext_return (type 0)))
+  (import "env" "ext_return" (func $ext_return (;0;) (type 0)))
   (import "env" "memory" (memory (;0;) 1 1))
-  (import "env" "gas" (func $start (type 2)))
+  (import "env" "gas" (func (;1;) (type 2)))
-  (func (;2;) (type 1)
+  (func $start (;2;) (type 1)
     i32.const 4
-    call $start
+    call 1
     i32.const 8
     i32.const 4
     call $ext_return
@@ -15,6 +15,6 @@
   )
   (func (;3;) (type 1))
   (export "call" (func 3))
-  (start 2)
+  (start $start)
   (data (;0;) (i32.const 8) "\01\02\03\04")
 )

tests/expectations/stack-height/global.wat

@@ -2,8 +2,8 @@
   (type (;0;) (func))
   (type (;1;) (func (param i32 i32) (result i32)))
   (type (;2;) (func (param i32)))
-  (import "env" "foo" (func $foo (type 0)))
+  (import "env" "foo" (func $foo (;0;) (type 0)))
-  (func $i32.add (type 1) (param i32 i32) (result i32)
+  (func $i32.add (;1;) (type 1) (param i32 i32) (result i32)
     local.get 0
     local.get 1
     i32.add
@@ -53,7 +53,7 @@
     i32.sub
     global.set 1
   )
-  (global $counter (mut i32) i32.const 1)
+  (global $counter (;0;) (mut i32) i32.const 1)
   (global (;1;) (mut i32) i32.const 0)
   (export "i32.add" (func 3))
 )

tests/expectations/stack-height/imports.wat

@@ -1,8 +1,8 @@
 (module
   (type (;0;) (func))
   (type (;1;) (func (param i32 i32) (result i32)))
-  (import "env" "foo" (func $foo (type 0)))
+  (import "env" "foo" (func $foo (;0;) (type 0)))
-  (import "env" "boo" (func $boo (type 0)))
+  (import "env" "boo" (func $boo (;1;) (type 0)))
   (func (;2;) (type 1) (param i32 i32) (result i32)
     call $foo
     call $boo

tests/expectations/stack-height/many_locals.wat

@@ -1,9 +1,9 @@
 (module
   (type (;0;) (func))
-  (func $one-group-many-locals (type 0)
+  (func $one-group-many-locals (;0;) (type 0)
     (local i64 i64 i32)
   )
-  (func $main (type 0)
+  (func $main (;1;) (type 0)
     global.get 0
     i32.const 5
     i32.add

tests/expectations/stack-height/start.wat

@@ -1,9 +1,9 @@
 (module
   (type (;0;) (func (param i32 i32)))
   (type (;1;) (func))
-  (import "env" "ext_return" (func $ext_return (type 0)))
+  (import "env" "ext_return" (func $ext_return (;0;) (type 0)))
   (import "env" "memory" (memory (;0;) 1 1))
-  (func $start (type 1)
+  (func $start (;1;) (type 1)
     (local i32)
   )
   (func (;2;) (type 1))

tests/expectations/stack-height/table.wat

@@ -2,7 +2,7 @@
   (type (;0;) (func))
   (type (;1;) (func (param i32)))
   (type (;2;) (func (param i32 i32) (result i32)))
-  (import "env" "foo" (func $foo (type 0)))
+  (import "env" "foo" (func $foo (;0;) (type 0)))
   (func (;1;) (type 1) (param i32)
     local.get 0
     i32.const 0
@@ -23,7 +23,7 @@
     global.set 0
     drop
   )
-  (func $i32.add (type 2) (param i32 i32) (result i32)
+  (func $i32.add (;2;) (type 2) (param i32 i32) (result i32)
     local.get 0
     local.get 1
     i32.add