compiler: Add is_tagged_tuple instruction

Rewrite the instruction stream on tagged tuple tests.
Tagged tuples means a tuple of any arity with an atom as its first element.
Typically records, ok-tuples and error-tuples.

from:
    ...
    {test,is_tuple,Fail,[Src]}.
    {test,test_arity,Fail,[Src,Sz]}.
    ...
    {get_tuple_element,Src,0,Dst}.
    ...
    {test,is_eq_exact,Fail,[Dst,Atom]}.
    ...
to:
    ...
    {test,is_tagged_tuple,Fail,[Src,Sz,Atom]}.
    ...

2 files changed, 23 insertions, 0 deletions

diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c
index 8be0f58227..9a91fdce08 100644
--- a/erts/emulator/beam/beam_emu.c
+++ b/erts/emulator/beam/beam_emu.c
@@ -850,6 +850,15 @@ do {                                            \
   } while (0)
 #endif
 
+#define IsTaggedTuple(Src,Arityval,Tag,Fail) \
+  do {                                       \
+    if (!(is_tuple(Src) &&                   \
+         (tuple_val(Src))[0] == Arityval &&  \
+         (tuple_val(Src))[1] == Tag)) {      \
+        Fail;                                \
+    }                                        \
+  } while (0)
+
 #define IsBoolean(X, Fail) if ((X) != am_true && (X) != am_false) { Fail; }
 
 #define IsBinary(Src, Fail) \
diff --git a/erts/emulator/beam/ops.tab b/erts/emulator/beam/ops.tab
index ec36b23059..9b5bd7a749 100644
--- a/erts/emulator/beam/ops.tab
+++ b/erts/emulator/beam/ops.tab
@@ -620,6 +620,20 @@ test_heap Need u==1 | put_list Y=y x==0 x==0 => test_heap_1_put_list Need Y
 %macro: test_heap_1_put_list TestHeapPutList -pack
 test_heap_1_put_list I y
 
+#
+# is_tagged_tuple Fail=f Src=rxy Arity Atom=a
+#
+
+is_tagged_tuple Fail Literal=q Arity Atom => \
+    move Literal x | is_tagged_tuple Fail x Arity Atom
+is_tagged_tuple Fail=f c Arity Atom  => jump Fail
+
+%macro:is_tagged_tuple IsTaggedTuple -fail_action
+
+is_tagged_tuple f r A a
+is_tagged_tuple f x A a
+is_tagged_tuple f y A a
+
 # Test tuple & arity (head)
 
 is_tuple Fail Literal=q => move Literal x | is_tuple Fail x