iskm/learnxinyminutes-docs
1
0
Fork 0
mirror of https://github.com/adambard/learnxinyminutes-docs.git synced 2024-12-23 17:41:41 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

update comments a bit

Browse Source
This commit is contained in:
Rett Berg 2019-11-16 12:44:47 -07:00
parent b27d3a088d
commit 4727925b1a
1 changed files with 9 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
wasm.html.markdown
View File

@ -223,7 +223,12 @@ contributors:
)
(export "apply_cos64" (func $apply_cos64))
;; Demonstration of how this C code might be written by hand
;; Wasm is a stack-based language, but for returning values more complicated
;; than an int/float, a memory stack has to be manually managed. One
;; approach is to use a mutable global to store the stack_ptr. We give
;; ourselves 1MiB of mem-stack and grow it downwards.
;;
;; Below is a demonstration of how this C code **might** be written by hand
;;
;; typedef struct {
;; int a;
@ -238,17 +243,11 @@ contributors:
;; sum_struct_t s = sum_struct_create(40, 2);
;; return s.a + s.b;
;; }
;;
;; Wasm is a stack-based language, but for returning values more complicated
;; than an int/float, a memory stack has to be manually managed. One ;;
;; approach is to use a mutable global to store the stack_ptr. We give
;; ourselves 1MiB of mem-stack and grow it downwards.
;;
;; Note: we are differentiating from the memstack (stack stored in memory)
;; and the "stack", which wasm implicitly uses to to pass and return values.
;; Unlike C, we must manage our own memory stack
(global $memstack_ptr (mut i32) (i32.const 65536))
;; structs can only be returned by reference
;; Structs can only be returned by reference
(func $sum_struct_create
(param $sum_struct_ptr i32)
(param $var$a i32)