[Guile-commits] 153/437: Make it clear stdarg like abstraction is not supported.

[Andy Wingo]

wingo pushed a commit to branch lightning
in repository guile.

commit 03559bb8cc47ad7a1f8ae5a35d128f06e1b736b9
Author: pcpa <address@hidden>
Date:   Fri Dec 14 15:21:39 2012 -0200

    Make it clear stdarg like abstraction is not supported.
    
        * include/lightning.h, include/lightning/jit_private.h,
        lib/jit_arm.c, lib/jit_mips.c, lib/jit_ppc.c, lib/jit_x86.c,
        lib/lightning.c: Make jit_ellipsis implementation not
        backend specific. It is not intended to handle va_list
        like objects at runtime, as jit_arg* and jit_getarg*
        return constant values resolved at parse time, so, effectively
        it is not possible to create printf like jit functions, as
        there is no va_start, va_arg, va_end, etc, abstraction. This
        limitation should be kept for the sake of making new ports
        easier.
---
 ChangeLog                       | 13 +++++++++++++
 include/lightning.h             |  7 -------
 include/lightning/jit_private.h |  7 ++++++-
 lib/jit_arm.c                   | 21 +++++++++------------
 lib/jit_mips.c                  | 10 +++-------
 lib/jit_ppc.c                   | 13 +++++--------
 lib/jit_x86.c                   | 15 ++++++---------
 lib/lightning.c                 | 26 +++++++++++++++++++++++++-
 8 files changed, 67 insertions(+), 45 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index c7149bf..b0802dd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,18 @@
 2012-12-14 Paulo Andrade <address@hidden>
 
+       * include/lightning.h, include/lightning/jit_private.h,
+       lib/jit_arm.c, lib/jit_mips.c, lib/jit_ppc.c, lib/jit_x86.c,
+       lib/lightning.c: Make jit_ellipsis implementation not
+       backend specific. It is not intended to handle va_list
+       like objects at runtime, as jit_arg* and jit_getarg*
+       return constant values resolved at parse time, so, effectively
+       it is not possible to create printf like jit functions, as
+       there is no va_start, va_arg, va_end, etc, abstraction. This
+       limitation should be kept for the sake of making new ports
+       easier.
+
+2012-12-14 Paulo Andrade <address@hidden>
+
        * include/lightning.h, lib/lightning.c: Add two extra wrapper
        functions to avoid need for excess pointer to/from word casts.
 
diff --git a/include/lightning.h b/include/lightning.h
index 3669695..35fcfa7 100644
--- a/include/lightning.h
+++ b/include/lightning.h
@@ -95,13 +95,6 @@ typedef jit_int32_t          jit_fpr_t;
 #define jit_class(reg)         ((reg) & 0xffff0000)
 #define jit_regno(reg)         ((reg) & 0x00007fff)
 
-#define jit_call_default       0
-/* assume only varags functions called are printf like, that is,
- * without a declared float/double argument */
-/* FIXME currently no way to create a varargs (or non varargs) jit function
- * if calling sequence changes for float/double arguments */
-#define jit_call_varargs       1
-
 typedef struct jit_node                jit_node_t;
 typedef struct jit_state       jit_state_t;
 
diff --git a/include/lightning/jit_private.h b/include/lightning/jit_private.h
index 6107ffa..959af0f 100644
--- a/include/lightning/jit_private.h
+++ b/include/lightning/jit_private.h
@@ -61,6 +61,9 @@
                                                 * returned by a "user" call
                                                 * to jit_get_reg() */
 
+#define jit_call_default       0
+#define jit_call_varargs       1
+
 #define jit_kind_register      1
 #define jit_kind_code          2
 #define jit_kind_word          3
@@ -194,12 +197,13 @@ struct jit_function {
        jit_int32_t      size;
        jit_int32_t      aoff;
        jit_int32_t      alen;
+       jit_int32_t      call;
     } self;
     struct {
        jit_int32_t      argi;
        jit_int32_t      argf;
        jit_int32_t      size;
-       jit_int32_t      kind;
+       jit_int32_t      call;
     } call;
     jit_node_t         *prolog;
     jit_node_t         *epilog;
@@ -220,6 +224,7 @@ struct jit_state {
     jit_node_t          *tail;
     jit_uint32_t         emit  : 1;    /* emit state entered */
     jit_uint32_t         again : 1;    /* start over emiting function */
+    jit_uint32_t         prepare : 1;  /* inside prepare/finish* block */
     jit_int32_t                  reglen;       /* number of registers */
     jit_regset_t         regarg;       /* cannot allocate */
     jit_regset_t         regsav;       /* automatic spill only once */
diff --git a/lib/jit_arm.c b/lib/jit_arm.c
index e4af92e..4ecdb0d 100644
--- a/lib/jit_arm.c
+++ b/lib/jit_arm.c
@@ -228,6 +228,7 @@ _jit_prolog(jit_state_t *_jit)
        _jit->function->self.aoff = -64;
     else
        _jit->function->self.aoff = 0;
+    _jit->function->self.call = jit_call_default;
     _jit->function->regoff = calloc(_jit->reglen, sizeof(jit_int32_t));
 
     _jit->function->prolog = jit_new_node_no_link(jit_code_prolog);
@@ -243,12 +244,6 @@ _jit_prolog(jit_state_t *_jit)
     jit_regset_new(_jit->function->regset);
 }
 
-void
-_jit_ellipsis(jit_state_t *_jit)
-{
-    _jit->function->call.kind = jit_call_varargs;
-}
-
 jit_int32_t
 _jit_allocai(jit_state_t *_jit, jit_int32_t length)
 {
@@ -355,7 +350,7 @@ jit_int32_t
 _jit_arg_f(jit_state_t *_jit)
 {
     jit_int32_t                offset;
-    if (jit_cpu.abi) {
+    if (jit_cpu.abi && !(_jit->function->self.call & jit_call_varargs)) {
        if (_jit->function->self.argf < 16)
            offset = _jit->function->self.argf++;
        else {
@@ -378,7 +373,7 @@ jit_int32_t
 _jit_arg_d(jit_state_t *_jit)
 {
     jit_int32_t                offset;
-    if (jit_cpu.abi) {
+    if (jit_cpu.abi && !(_jit->function->self.call & jit_call_varargs)) {
        if (_jit->function->self.argf < 15) {
            if (_jit->function->self.argf & 1)
                ++_jit->function->self.argf;
@@ -525,7 +520,7 @@ void
 _jit_pushargr_f(jit_state_t *_jit, jit_int32_t u)
 {
     assert(_jit->function);
-    if (jit_cpu.abi && !(_jit->function->call.kind & jit_call_varargs)) {
+    if (jit_cpu.abi && !(_jit->function->call.call & jit_call_varargs)) {
        if (_jit->function->call.argf < 16) {
            jit_movr_f(JIT_FA0 - _jit->function->call.argf, u);
            ++_jit->function->call.argf;
@@ -549,7 +544,7 @@ _jit_pushargi_f(jit_state_t *_jit, jit_float32_t u)
     jit_int32_t                regno;
 
     assert(_jit->function);
-    if (jit_cpu.abi && !(_jit->function->call.kind & jit_call_varargs)) {
+    if (jit_cpu.abi && !(_jit->function->call.call & jit_call_varargs)) {
        if (_jit->function->call.argf < 16) {
            jit_movi_f(JIT_FA0 - _jit->function->call.argf, u);
            ++_jit->function->call.argf;
@@ -574,7 +569,7 @@ void
 _jit_pushargr_d(jit_state_t *_jit, jit_int32_t u)
 {
     assert(_jit->function);
-    if (jit_cpu.abi && !(_jit->function->call.kind & jit_call_varargs)) {
+    if (jit_cpu.abi && !(_jit->function->call.call & jit_call_varargs)) {
        if (_jit->function->call.argf < 15) {
            if (_jit->function->call.argf & 1)
                ++_jit->function->call.argf;
@@ -604,7 +599,7 @@ _jit_pushargi_d(jit_state_t *_jit, jit_float64_t u)
     jit_int32_t                regno;
 
     assert(_jit->function);
-    if (jit_cpu.abi && !(_jit->function->call.kind & jit_call_varargs)) {
+    if (jit_cpu.abi && !(_jit->function->call.call & jit_call_varargs)) {
        if (_jit->function->call.argf < 15) {
            if (_jit->function->call.argf & 1)
                ++_jit->function->call.argf;
@@ -664,6 +659,7 @@ _jit_finishr(jit_state_t *_jit, jit_int32_t r0)
     node->w.w = _jit->function->call.argf;
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 0;
 }
 
 jit_node_t *
@@ -679,6 +675,7 @@ _jit_finishi(jit_state_t *_jit, jit_pointer_t i0)
     node->w.w = _jit->function->call.argf;
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 0;
     return (node);
 }
 
diff --git a/lib/jit_mips.c b/lib/jit_mips.c
index bfca206..d3cca00 100644
--- a/lib/jit_mips.c
+++ b/lib/jit_mips.c
@@ -135,6 +135,7 @@ _jit_prolog(jit_state_t *_jit)
     _jit->function->self.size = stack_framesize;
     _jit->function->self.argi = _jit->function->self.argf =
        _jit->function->self.aoff = _jit->function->self.alen = 0;
+    _jit->function->self.call = jit_call_default;
     _jit->function->regoff = calloc(_jit->reglen, sizeof(jit_int32_t));
 
     _jit->function->prolog = jit_new_node_no_link(jit_code_prolog);
@@ -150,12 +151,6 @@ _jit_prolog(jit_state_t *_jit)
     jit_regset_new(_jit->function->regset);
 }
 
-void
-_jit_ellipsis(jit_state_t *_jit)
-{
-    _jit->function->call.kind = jit_call_varargs;
-}
-
 jit_int32_t
 _jit_allocai(jit_state_t *_jit, jit_int32_t length)
 {
@@ -612,6 +607,7 @@ _jit_finishr(jit_state_t *_jit, jit_int32_t r0)
     call->w.w = _jit->function->self.argf;
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 0;
 }
 
 jit_node_t *
@@ -629,7 +625,7 @@ _jit_finishi(jit_state_t *_jit, jit_pointer_t i0)
     call->w.w = _jit->function->call.argf;
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
-
+    _jit->prepare = 0;
     return (node);
 }
 
diff --git a/lib/jit_ppc.c b/lib/jit_ppc.c
index 6e5da81..df6007e 100644
--- a/lib/jit_ppc.c
+++ b/lib/jit_ppc.c
@@ -141,6 +141,7 @@ _jit_prolog(jit_state_t *_jit)
        _jit->function->self.aoff = _jit->function->self.alen = 0;
     /* float conversion */
     _jit->function->self.aoff = -8;
+    _jit->function->self.call = jit_call_default;
     _jit->function->regoff = calloc(_jit->reglen, sizeof(jit_int32_t));
 
     _jit->function->prolog = jit_new_node_no_link(jit_code_prolog);
@@ -156,12 +157,6 @@ _jit_prolog(jit_state_t *_jit)
     jit_regset_new(_jit->function->regset);
 }
 
-void
-_jit_ellipsis(jit_state_t *_jit)
-{
-    _jit->function->call.kind = jit_call_varargs;
-}
-
 jit_int32_t
 _jit_allocai(jit_state_t *_jit, jit_int32_t length)
 {
@@ -425,7 +420,7 @@ _jit_pushargr_d(jit_state_t *_jit, jit_int32_t u)
     if (_jit->function->call.argf < 8) {
        jit_movr_d(JIT_FA0 - _jit->function->call.argf, u);
        ++_jit->function->call.argf;
-       if (!(_jit->function->call.kind & jit_call_varargs))
+       if (!(_jit->function->call.call & jit_call_varargs))
            return;
     }
     if (_jit->function->call.argi < 8) {
@@ -452,7 +447,7 @@ _jit_pushargi_d(jit_state_t *_jit, jit_float64_t u)
     if (_jit->function->call.argf < 8) {
        jit_movi_d(JIT_FA0 - _jit->function->call.argf, u);
        ++_jit->function->call.argf;
-       if (!(_jit->function->call.kind & jit_call_varargs))
+       if (!(_jit->function->call.call & jit_call_varargs))
            return;
     }
     regno = jit_get_reg(jit_class_fpr);
@@ -505,6 +500,7 @@ _jit_finishr(jit_state_t *_jit, jit_int32_t r0)
     call->w.w = _jit->function->call.argf;
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 0;
 }
 
 jit_node_t *
@@ -519,6 +515,7 @@ _jit_finishi(jit_state_t *_jit, jit_pointer_t i0)
     node->w.w = _jit->function->call.argf;
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 0;
     return (node);
 }
 
diff --git a/lib/jit_x86.c b/lib/jit_x86.c
index 918af41..8386a85 100644
--- a/lib/jit_x86.c
+++ b/lib/jit_x86.c
@@ -305,6 +305,7 @@ _jit_prolog(jit_state_t *_jit)
        _jit->function->self.aoff = _jit->function->self.alen = 0;
     /* sse/x87 conversion */
     _jit->function->self.aoff = -8;
+    _jit->function->self.call = jit_call_default;
     _jit->function->regoff = calloc(_jit->reglen, sizeof(jit_int32_t));
 
     _jit->function->prolog = jit_new_node_no_link(jit_code_prolog);
@@ -320,12 +321,6 @@ _jit_prolog(jit_state_t *_jit)
     jit_regset_new(_jit->function->regset);
 }
 
-void
-_jit_ellipsis(jit_state_t *_jit)
-{
-    _jit->function->call.kind = jit_call_varargs;
-}
-
 jit_int32_t
 _jit_allocai(jit_state_t *_jit, jit_int32_t length)
 {
@@ -732,7 +727,7 @@ _jit_finishr(jit_state_t *_jit, jit_int32_t r0)
     if (_jit->function->self.alen < _jit->function->call.size)
        _jit->function->self.alen = _jit->function->call.size;
 #if __WORDSIZE == 64
-    if (_jit->function->call.kind & jit_call_varargs) {
+    if (_jit->function->call.call & jit_call_varargs) {
        if (jit_regno(reg) == _RAX) {
            reg = jit_get_reg(jit_class_gpr);
            jit_movr(reg, _RAX);
@@ -750,6 +745,7 @@ _jit_finishr(jit_state_t *_jit, jit_int32_t r0)
     call->w.w = _jit->function->call.argf;
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 0;
 }
 
 jit_node_t *
@@ -764,13 +760,13 @@ _jit_finishi(jit_state_t *_jit, jit_pointer_t i0)
     if (_jit->function->self.alen < _jit->function->call.size)
        _jit->function->self.alen = _jit->function->call.size;
 #if __WORDSIZE == 64
-    if (_jit->function->call.kind & jit_call_varargs)
+    if (_jit->function->call.call & jit_call_varargs)
        jit_regset_setbit(_jit->regarg, _RAX);
     reg = jit_get_reg(jit_class_gpr);
     node = jit_movi(reg, (jit_word_t)i0);
     jit_finishr(reg);
     jit_unget_reg(reg);
-    if (_jit->function->call.kind & jit_call_varargs)
+    if (_jit->function->call.call & jit_call_varargs)
        jit_regset_clrbit(_jit->regarg, _RAX);
 #else
     node = jit_calli(i0);
@@ -779,6 +775,7 @@ _jit_finishi(jit_state_t *_jit, jit_pointer_t i0)
 #endif
     _jit->function->call.argi = _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 0;
     return (node);
 }
 
diff --git a/lib/lightning.c b/lib/lightning.c
index 94a3580..dc9dcd9 100644
--- a/lib/lightning.c
+++ b/lib/lightning.c
@@ -725,10 +725,34 @@ void
 _jit_prepare(jit_state_t *_jit)
 {
     assert(_jit->function);
-    _jit->function->call.kind = jit_call_default;
+    _jit->function->call.call = jit_call_default;
     _jit->function->call.argi =
        _jit->function->call.argf =
        _jit->function->call.size = 0;
+    _jit->prepare = 1;
+}
+
+/* If declaring a jit function as varargs, in most backends it does
+ * not change anything. Currently only exception is arm backend, that
+ * if running in hardware float abi, switches to software float abi
+ * if "self" function is varargs. Otherwise, there is no logic to
+ * handle va_list like objects that need to parse runtime state, and
+ * that is mainly because jit_arg* and jit_getarg* work only with
+ * constants values, and one must not expect them to be handled at
+ * runtime, they are parsed only once (same applies to jit_allocai,
+ * that has no jit_allocar counterpart).
+ */
+void
+_jit_ellipsis(jit_state_t *_jit)
+{
+    if (_jit->prepare) {
+       assert(!_jit->function->call.call & jit_call_varargs);
+       _jit->function->call.call |= jit_call_varargs;
+    }
+    else {
+       assert(!_jit->function->self.call & jit_call_varargs);
+       _jit->function->self.call |= jit_call_varargs;
+    }
 }
 
 void