bv-f32-ref and bv-f64-ref return raw f64 values

* module/language/tree-il/compile-cps.scm (convert): Box results of
  bv-f32-ref and bv-f64-ref.

* libguile/vm-engine.c (bv-f32-ref, bv-f64-ref): Results are raw.

* module/system/vm/assembler.scm (emit-scm->f64, emit-f64->scm):
  Export.

* module/language/cps/compile-bytecode.scm (compile-function):
* module/language/cps/effects-analysis.scm:
* module/language/cps/types.scm: Add support for scm->f64 and f64->scm.

* module/language/cps/slot-allocation.scm (compute-var-representations):
  Add cases for primops returning raw values.

7 files changed, 53 insertions, 7 deletions

diff --git a/libguile/vm-engine.c b/libguile/vm-engine.c
index 75e1694cd..82ae1c0cb 100644
--- a/libguile/vm-engine.c
+++ b/libguile/vm-engine.c
@@ -3032,14 +3032,22 @@ VM_NAME (scm_i_thread *thread, struct scm_vm *vp,
     i = SCM_I_INUM (idx);                                               \
     float_ptr = (type *) (SCM_BYTEVECTOR_CONTENTS (bv) + i);		\
 									\
-    SYNC_IP ();                                                         \
     if (SCM_LIKELY (SCM_I_INUMP (idx)					\
                     && (i >= 0)						\
                     && (i + size <= SCM_BYTEVECTOR_LENGTH (bv))		\
                     && (ALIGNED_P (float_ptr, type))))			\
-      RETURN (scm_from_double (*float_ptr));				\
+      {                                                                 \
+        SP_SET_F64 (dst, *float_ptr);                                   \
+        NEXT (1);                                                       \
+      }                                                                 \
     else                                                                \
-      RETURN (scm_bytevector_ ## fn_stem ## _native_ref (bv, idx));	\
+      {                                                                 \
+        SCM val;                                                        \
+        SYNC_IP ();                                                     \
+        val = scm_bytevector_ ## fn_stem ## _native_ref (bv, idx);      \
+        SP_SET_F64 (dst, scm_to_double (val));                          \
+        NEXT (1);                                                       \
+      }                                                                 \
   } while (0)
 
   VM_DEFINE_OP (116, bv_u8_ref, "bv-u8-ref", OP1 (X8_S8_S8_S8) | OP_DST)
diff --git a/module/language/cps/compile-bytecode.scm b/module/language/cps/compile-bytecode.scm
index 96200a83d..49b684cc4 100644
--- a/module/language/cps/compile-bytecode.scm
+++ b/module/language/cps/compile-bytecode.scm
@@ -181,6 +181,10 @@
                                     (constant n)))
         (($ $primcall 'builtin-ref (name))
          (emit-builtin-ref asm (from-sp dst) (constant name)))
+        (($ $primcall 'scm->f64 (src))
+         (emit-scm->f64 asm (from-sp dst) (from-sp (slot src))))
+        (($ $primcall 'f64->scm (src))
+         (emit-f64->scm asm (from-sp dst) (from-sp (slot src))))
         (($ $primcall 'bv-u8-ref (bv idx))
          (emit-bv-u8-ref asm (from-sp dst) (from-sp (slot bv))
                          (from-sp (slot idx))))
diff --git a/module/language/cps/effects-analysis.scm b/module/language/cps/effects-analysis.scm
index 778855de5..3542a1e74 100644
--- a/module/language/cps/effects-analysis.scm
+++ b/module/language/cps/effects-analysis.scm
@@ -351,6 +351,11 @@ is or might be a read or a write to the same location as A."
   ((string->number _)              (&read-object &string)      &type-check)
   ((string-length s)                                           &type-check))
 
+;; Unboxed floats.
+(define-primitive-effects
+  ((scm->f64 _)                                                &type-check)
+  ((f64->scm _)))
+
 ;; Bytevectors.
 (define-primitive-effects
   ((bytevector-length _)                                       &type-check)
diff --git a/module/language/cps/slot-allocation.scm b/module/language/cps/slot-allocation.scm
index ad4e524e7..6fc2a5399 100644
--- a/module/language/cps/slot-allocation.scm
+++ b/module/language/cps/slot-allocation.scm
@@ -790,9 +790,7 @@ are comparable with eqv?.  A tmp slot may be used."
              (($ $values (arg))
               (intmap-add representations var
                           (intmap-ref representations arg)))
-             ;; FIXME: Placeholder for as-yet-unwritten primitive
-             ;; operations that define unboxed f64 values.
-             (($ $primcall 'scm->f64)
+             (($ $primcall (or 'scm->f64 'bv-f32-ref 'bv-f64-ref))
               (intmap-add representations var 'f64))
              (_
               (intmap-add representations var 'scm))))
diff --git a/module/language/cps/types.scm b/module/language/cps/types.scm
index 55cde2744..74b5d48de 100644
--- a/module/language/cps/types.scm
+++ b/module/language/cps/types.scm
@@ -673,6 +673,24 @@ minimum, and maximum."
 
 
 ;;;
+;;; Unboxed double-precision floating-point numbers.
+;;;
+
+(define-type-checker (scm->f64 scm)
+  (check-type scm &real -inf.0 +inf.0))
+(define-type-inferrer (scm->f64 scm result)
+  (restrict! scm &flonum -inf.0 +inf.0)
+  (define! result &flonum (&min scm) (&max scm)))
+
+(define-type-checker (f64->scm f64)
+  #t)
+(define-type-inferrer (f64->scm f64 result)
+  (define! result &flonum (&min f64) (&max f64)))
+
+
+
+
+;;;
 ;;; Bytevectors.
 ;;;
 
diff --git a/module/language/tree-il/compile-cps.scm b/module/language/tree-il/compile-cps.scm
index 0664b2c4d..88e729852 100644
--- a/module/language/tree-il/compile-cps.scm
+++ b/module/language/tree-il/compile-cps.scm
@@ -555,6 +555,17 @@
                       ($ (lp args ktail)))))))))))
       ((prim-instruction name)
        => (lambda (instruction)
+            (define (box+adapt-arity cps k src out)
+              (case instruction
+                ((bv-f32-ref bv-f64-ref)
+                 (with-cps cps
+                   (letv f64)
+                   (let$ k (adapt-arity k src out))
+                   (letk kbox ($kargs ('f64) (f64)
+                                ($continue k src ($primcall 'f64->scm (f64)))))
+                   kbox))
+                (else
+                 (adapt-arity cps k src out))))
             (convert-args cps args
               (lambda (cps args)
                 ;; Tree-IL primcalls are sloppy, in that it could be
@@ -566,7 +577,7 @@
                   ((out . in)
                    (if (= in (length args))
                        (with-cps cps
-                         (let$ k (adapt-arity k src out))
+                         (let$ k (box+adapt-arity k src out))
                          (build-term
                            ($continue k src
                              ($primcall instruction args))))
diff --git a/module/system/vm/assembler.scm b/module/system/vm/assembler.scm
index dd96709e5..9cb04bbed 100644
--- a/module/system/vm/assembler.scm
+++ b/module/system/vm/assembler.scm
@@ -155,6 +155,8 @@
             (emit-struct-set!* . emit-struct-set!)
             (emit-class-of* . emit-class-of)
             emit-make-array
+            (emit-scm->f64* . emit-scm->f64)
+            (emit-f64->scm* . emit-f64->scm)
             (emit-bv-u8-ref* . emit-bv-u8-ref)
             (emit-bv-s8-ref* . emit-bv-s8-ref)
             (emit-bv-u16-ref* . emit-bv-u16-ref)