wary jumps

qbe_emit.cm

@@ -633,6 +633,15 @@ ${sr("gc", "%idx_slot")}
 ${sr("a", "%fn_slot")}
   %r =l call $cell_rt_frame(l %ctx, l %a, l %nargs)
 ${alloc_tail("%r")}
+}`
+
+  // apply(ctx, fp, dest, fn_slot, arg_slot)
+  h[] = `export function l $__apply_ss(l %ctx, l %fp, l %dest, l %fn_slot, l %arg_slot) ${lb}
+@entry
+${sr("a", "%fn_slot")}
+${sr("b", "%arg_slot")}
+  %r =l call $cell_rt_apply(l %ctx, l %a, l %b)
+${alloc_tail("%r")}
 }`
 
   // goframe(ctx, fp, dest, fn_slot, nargs)
@@ -1023,6 +1032,18 @@ var qbe_emit = function(ir, qbe, export_name) {
     var jnn_lbl = null
     var jnn_idx = null
     var jnn_backedge = false
+    var wt_lbl = null
+    var wt_idx = null
+    var wt_backedge = false
+    var wf_lbl = null
+    var wf_idx = null
+    var wf_backedge = false
+    var jn_lbl = null
+    var jn_idx = null
+    var jn_backedge = false
+    var je_lbl = null
+    var je_idx = null
+    var je_backedge = false
     var truthy = null
     var lhs_d = null
     var rhs_d = null
@@ -2625,8 +2646,8 @@ var qbe_emit = function(ir, qbe, export_name) {
         jt_lbl = sanitize(a2)
         jt_idx = label_pos[jt_lbl]
         jt_backedge = jt_idx != null && jt_idx < instr_idx
-        truthy = emit_truthy_w(v)
+        emit(`  %${p}_take =w ceql ${v}, ${text(qbe.js_true)}`)
-        emit(`  jnz ${truthy}, @${p}_take, @${p}_f`)
+        emit(`  jnz %${p}_take, @${p}_take, @${p}_f`)
         emit(`@${p}_take`)
         if (jt_backedge) {
           emit_backedge_branch(jt_lbl)
@@ -2642,8 +2663,8 @@ var qbe_emit = function(ir, qbe, export_name) {
         jf_lbl = sanitize(a2)
         jf_idx = label_pos[jf_lbl]
         jf_backedge = jf_idx != null && jf_idx < instr_idx
-        truthy = emit_truthy_w(v)
+        emit(`  %${p}_take =w ceql ${v}, ${text(qbe.js_false)}`)
-        emit(`  jnz ${truthy}, @${p}_t, @${p}_take`)
+        emit(`  jnz %${p}_take, @${p}_take, @${p}_t`)
         emit(`@${p}_take`)
         if (jf_backedge) {
           emit_backedge_branch(jf_lbl)
@@ -2653,6 +2674,74 @@ var qbe_emit = function(ir, qbe, export_name) {
         emit(`@${p}_t`)
         continue
       }
+      if (op == "wary_true") {
+        v = s_read(a1)
+        p = fresh()
+        wt_lbl = sanitize(a2)
+        wt_idx = label_pos[wt_lbl]
+        wt_backedge = wt_idx != null && wt_idx < instr_idx
+        truthy = emit_truthy_w(v)
+        emit(`  jnz ${truthy}, @${p}_take, @${p}_f`)
+        emit(`@${p}_take`)
+        if (wt_backedge) {
+          emit_backedge_branch(wt_lbl)
+        } else {
+          emit(`  jmp @${wt_lbl}`)
+        }
+        emit(`@${p}_f`)
+        continue
+      }
+      if (op == "wary_false") {
+        v = s_read(a1)
+        p = fresh()
+        wf_lbl = sanitize(a2)
+        wf_idx = label_pos[wf_lbl]
+        wf_backedge = wf_idx != null && wf_idx < instr_idx
+        truthy = emit_truthy_w(v)
+        emit(`  jnz ${truthy}, @${p}_t, @${p}_take`)
+        emit(`@${p}_take`)
+        if (wf_backedge) {
+          emit_backedge_branch(wf_lbl)
+        } else {
+          emit(`  jmp @${wf_lbl}`)
+        }
+        emit(`@${p}_t`)
+        continue
+      }
+      if (op == "jump_null") {
+        v = s_read(a1)
+        p = fresh()
+        jn_lbl = sanitize(a2)
+        jn_idx = label_pos[jn_lbl]
+        jn_backedge = jn_idx != null && jn_idx < instr_idx
+        emit(`  %${p} =w ceql ${v}, ${text(qbe.js_null)}`)
+        if (jn_backedge) {
+          emit(`  jnz %${p}, @${p}_bn, @${p}_n`)
+          emit(`@${p}_bn`)
+          emit_backedge_branch(jn_lbl)
+        } else {
+          emit(`  jnz %${p}, @${jn_lbl}, @${p}_n`)
+        }
+        emit(`@${p}_n`)
+        continue
+      }
+      if (op == "jump_empty") {
+        v = s_read(a1)
+        p = fresh()
+        je_lbl = sanitize(a2)
+        je_idx = label_pos[je_lbl]
+        je_backedge = je_idx != null && je_idx < instr_idx
+        emit(`  %${p} =w ceql ${v}, ${text(qbe.js_empty_text)}`)
+        if (je_backedge) {
+          emit(`  jnz %${p}, @${p}_bn, @${p}_n`)
+          emit(`@${p}_bn`)
+          emit_backedge_branch(je_lbl)
+        } else {
+          emit(`  jnz %${p}, @${je_lbl}, @${p}_n`)
+        }
+        emit(`@${p}_n`)
+        continue
+      }
       if (op == "jump_not_null") {
         v = s_read(a1)
         p = fresh()
@@ -2678,6 +2767,11 @@ var qbe_emit = function(ir, qbe, export_name) {
         emit_exc_check()
         continue
       }
+      if (op == "apply") {
+        emit(`  %fp =l call $__apply_ss(l %ctx, l %fp, l ${text(a1)}, l ${text(a2)}, l ${text(a3)})`)
+        emit_exc_check()
+        continue
+      }
       if (op == "setarg") {
         v = s_read(a1)
         lhs = s_read(a3)

source/qbe_helpers.c

@@ -639,6 +639,30 @@ static int cell_check_call_arity(JSContext *ctx, JSFunction *fn, int argc) {
   return 1;
 }
 
+JSValue cell_rt_apply(JSContext *ctx, JSValue fn_val, JSValue arg_val) {
+  if (!mist_is_function(fn_val))
+    return fn_val;
+
+  JSFunction *fn = JS_VALUE_GET_FUNCTION(fn_val);
+  if (!mist_is_array(arg_val)) {
+    if (!cell_check_call_arity(ctx, fn, 1))
+      return JS_EXCEPTION;
+    return JS_CallInternal(ctx, fn_val, JS_NULL, 1, &arg_val, 0);
+  }
+
+  JSArray *arr = JS_VALUE_GET_ARRAY(arg_val);
+  int len = arr->len;
+  if (!cell_check_call_arity(ctx, fn, len))
+    return JS_EXCEPTION;
+  if (len == 0)
+    return JS_CallInternal(ctx, fn_val, JS_NULL, 0, NULL, 0);
+
+  JSValue args[len];
+  for (int i = 0; i < len; i++)
+    args[i] = arr->values[i];
+  return JS_CallInternal(ctx, fn_val, JS_NULL, len, args, 0);
+}
+
 static inline void cell_copy_args_0_4(JSValue *fp, JSValue *argv, int copy) {
   /* fp[0] is `this`; copy args into fp[1..4] */
   switch (copy) {