Bug 1569137: Use the baldrdash calling convention for libcall expansion; r=jseward

Differential Revision: https://phabricator.services.mozilla.com/D40610

--HG--
extra : moz-landing-system : lando

js/src/jit-test/tests/wasm/regress/bug1569137.js

@@ -0,0 +1,65 @@
+let { exports: { f } } = wasmEvalText(`
+(module
+ (memory $0 1 1)
+
+ (func (export "f") (result f32)
+  (local $0 i32) (local $1 f64) (local $2 i32)
+
+  (set_local 0 (i32.const 134219779))
+  (set_local 1 (f64.const 3810600700439633677210579e165))
+
+  (f32.floor
+   (loop $label$2 (result f32)
+    (br_if $label$2
+     (i32.load offset=3 align=2
+       (block $label$4 (result i32)
+        (drop
+         (if (result f64)
+             (br_if $label$4
+              (i32.const 4883)
+                (i32.const -124)
+          )
+          (f64.const 77)
+          (block (result f64)
+           (drop
+             (br_if $label$4
+              (i32.const 4194304)
+              (i32.const -8192)
+            )
+           )
+           (return
+            (f32.const 4294967296)
+           )
+          )
+         )
+        )
+          (br_if $label$4
+             (br_if $label$4
+              (i32.const -90)
+               (br_if $label$4
+                (br_if $label$4
+                 (local.get $2)
+                 (i32.const -16)
+                )
+                (i32.const 15656)
+               )
+             )
+          (block $label$18 (result i32)
+           (i32.eqz
+            (br_if $label$4
+                 (i32.const -1)
+                 (i32.const 15)
+           )
+          )
+         )
+        )
+       )
+     )
+    )
+    (f32.const 23)
+   )
+  )
+ )
+)`);
+
+f();

js/src/wasm/cranelift/src/isa.rs

@@ -109,6 +109,9 @@ fn make_shared_flags(env_flags: &Option<EnvVariableFlags>) -> settings::SetResul
     //
     sb.set("baldrdash_prologue_words", "3")?;
 
+    // Make sure that libcalls use the supplementary VMContext argument.
+    sb.set("libcall_call_conv", "baldrdash")?;
+
     // Assembler::PatchDataWithValueCheck expects -1 stored where a function address should be
     // patched in.
     sb.enable("allones_funcaddrs")?;