Remove FunctionType (#2510)

Function signatures were previously redundantly stored on Function
objects as well as on FunctionType objects. These two signature
representations had to always be kept in sync, which was error-prone
and needlessly complex. This PR takes advantage of the new ability of
Type to represent multiple value types by consolidating function
signatures as a pair of Types (params and results) stored on the
Function object.

Since there are no longer module-global named function types,
significant changes had to be made to the printing and emitting of
function types, as well as their parsing and manipulation in various
passes.

The C and JS APIs and their tests also had to be updated to remove
named function types.

1 files changed, 9 insertions, 11 deletions

diff --git a/test/lld/em_asm_shared.wat.out b/test/lld/em_asm_shared.wat.out
index f3b676f24..c31d75e8c 100644
--- a/test/lld/em_asm_shared.wat.out
+++ b/test/lld/em_asm_shared.wat.out
@@ -1,11 +1,9 @@
 (module
- (type $0 (func (param i32 i32 i32) (result i32)))
- (type $1 (func))
- (type $2 (func (result i32)))
- (type $3 (func (param i32 i32) (result i32)))
- (type $FUNCSIG$i (func (result i32)))
- (type $FUNCSIG$vi (func (param i32)))
- (type $FUNCSIG$iiii (func (param i32 i32 i32) (result i32)))
+ (type $none_=>_i32 (func (result i32)))
+ (type $none_=>_none (func))
+ (type $i32_=>_none (func (param i32)))
+ (type $i32_i32_=>_i32 (func (param i32 i32) (result i32)))
+ (type $i32_i32_i32_=>_i32 (func (param i32 i32 i32) (result i32)))
  (import "env" "memory" (memory $0 0))
  (data (global.get $gimport$3) "{ Module.print(\"Hello world\"); }\00\00{ return $0 + $1; }\00ii\00{ Module.print(\"Got \" + $0); }\00i\00")
  (import "env" "table" (table $0 0 funcref))
@@ -29,13 +27,13 @@
  (export "_ZN20__em_asm_sig_builderI19__em_asm_type_tupleIJiEEE6bufferE" (global $global$2))
  (export "main" (func $main))
  (export "__post_instantiate" (func $__post_instantiate))
- (func $__wasm_call_ctors (; 6 ;) (type $1)
+ (func $__wasm_call_ctors (; 6 ;)
   (call $__wasm_apply_relocs)
  )
- (func $__wasm_apply_relocs (; 7 ;) (type $1)
+ (func $__wasm_apply_relocs (; 7 ;)
   (nop)
  )
- (func $__original_main (; 8 ;) (type $2) (result i32)
+ (func $__original_main (; 8 ;) (result i32)
   (local $0 i32)
   (local $1 i32)
   (call $stackRestore
@@ -94,7 +92,7 @@
   )
   (i32.const 0)
  )
- (func $main (; 9 ;) (type $3) (param $0 i32) (param $1 i32) (result i32)
+ (func $main (; 9 ;) (param $0 i32) (param $1 i32) (result i32)
   (call $__original_main)
  )
  (func $__post_instantiate (; 10 ;)