Don't pass vmctx to component libcalls (#10937)

* Don't pass vmctx to component libcalls

Take a leaf out of the core libcalls book where the `from_vmctx` call is
baked in as part of each libcall so libcalls can receive safer arguments
by default. There's still much `unsafe` in the libcalls due to their
arguments or accessing `*instance.store()`, but this latter part will be
fixed in a follow-up commit soon.

* Fix dead argument warnings

Author: alexcrichton

crates/cranelift/src/compiler/component.rs

@@ -1547,6 +1547,7 @@ impl TrampolineCompiler<'_> {
         let to_base = self.load_runtime_memory_base(vmctx, to);
 
         let mut args = Vec::new();
+        args.push(vmctx);
 
         let uses_retptr = match op {
             Transcode::Utf16ToUtf8

crates/environ/src/component.rs

@@ -156,18 +156,18 @@ macro_rules! foreach_builtin_component_function {
 
             trap(vmctx: vmctx, code: u8);
 
-            utf8_to_utf8(src: ptr_u8, len: size, dst: ptr_u8) -> bool;
-            utf16_to_utf16(src: ptr_u16, len: size, dst: ptr_u16) -> bool;
-            latin1_to_latin1(src: ptr_u8, len: size, dst: ptr_u8) -> bool;
-            latin1_to_utf16(src: ptr_u8, len: size, dst: ptr_u16) -> bool;
-            utf8_to_utf16(src: ptr_u8, len: size, dst: ptr_u16) -> size;
-            utf16_to_utf8(src: ptr_u16, src_len: size, dst: ptr_u8, dst_len: size, ret2: ptr_size) -> size;
-            latin1_to_utf8(src: ptr_u8, src_len: size, dst: ptr_u8, dst_len: size, ret2: ptr_size) -> size;
-            utf16_to_compact_probably_utf16(src: ptr_u16, len: size, dst: ptr_u16) -> size;
-            utf8_to_latin1(src: ptr_u8, len: size, dst: ptr_u8, ret2: ptr_size) -> size;
-            utf16_to_latin1(src: ptr_u16, len: size, dst: ptr_u8, ret2: ptr_size) -> size;
-            utf8_to_compact_utf16(src: ptr_u8, src_len: size, dst: ptr_u16, dst_len: size, bytes_so_far: size) -> size;
-            utf16_to_compact_utf16(src: ptr_u16, src_len: size, dst: ptr_u16, dst_len: size, bytes_so_far: size) -> size;
+            utf8_to_utf8(vmctx: vmctx, src: ptr_u8, len: size, dst: ptr_u8) -> bool;
+            utf16_to_utf16(vmctx: vmctx, src: ptr_u16, len: size, dst: ptr_u16) -> bool;
+            latin1_to_latin1(vmctx: vmctx, src: ptr_u8, len: size, dst: ptr_u8) -> bool;
+            latin1_to_utf16(vmctx: vmctx, src: ptr_u8, len: size, dst: ptr_u16) -> bool;
+            utf8_to_utf16(vmctx: vmctx, src: ptr_u8, len: size, dst: ptr_u16) -> size;
+            utf16_to_utf8(vmctx: vmctx, src: ptr_u16, src_len: size, dst: ptr_u8, dst_len: size, ret2: ptr_size) -> size;
+            latin1_to_utf8(vmctx: vmctx, src: ptr_u8, src_len: size, dst: ptr_u8, dst_len: size, ret2: ptr_size) -> size;
+            utf16_to_compact_probably_utf16(vmctx: vmctx, src: ptr_u16, len: size, dst: ptr_u16) -> size;
+            utf8_to_latin1(vmctx: vmctx, src: ptr_u8, len: size, dst: ptr_u8, ret2: ptr_size) -> size;
+            utf16_to_latin1(vmctx: vmctx, src: ptr_u16, len: size, dst: ptr_u8, ret2: ptr_size) -> size;
+            utf8_to_compact_utf16(vmctx: vmctx, src: ptr_u8, src_len: size, dst: ptr_u16, dst_len: size, bytes_so_far: size) -> size;
+            utf16_to_compact_utf16(vmctx: vmctx, src: ptr_u16, src_len: size, dst: ptr_u16, dst_len: size, bytes_so_far: size) -> size;
         }
     };
 }