diff mbox series

[v10.5,01/20] tcg: Allow multiple word entries into the constant pool

Message ID 20180117161435.28981-2-richard.henderson@linaro.org
State Superseded
Headers show
Series tcg: generic vector operations | expand

Commit Message

Richard Henderson Jan. 17, 2018, 4:14 p.m. UTC 
This will be required for storing vector constants.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

---
 tcg/tcg-pool.inc.c | 115 +++++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 93 insertions(+), 22 deletions(-)

-- 
2.14.3

Comments

Peter Maydell Jan. 22, 2018, 6:35 p.m. UTC | #1 
On 17 January 2018 at 16:14, Richard Henderson
<richard.henderson@linaro.org> wrote:
> This will be required for storing vector constants.

>

> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

> ---

>  tcg/tcg-pool.inc.c | 115 +++++++++++++++++++++++++++++++++++++++++++----------

>  1 file changed, 93 insertions(+), 22 deletions(-)

>

> diff --git a/tcg/tcg-pool.inc.c b/tcg/tcg-pool.inc.c

> index 8a85131405..0f76e7bee3 100644

> --- a/tcg/tcg-pool.inc.c

> +++ b/tcg/tcg-pool.inc.c

> @@ -22,39 +22,110 @@

>

>  typedef struct TCGLabelPoolData {

>      struct TCGLabelPoolData *next;

> -    tcg_target_ulong data;

>      tcg_insn_unit *label;

> -    intptr_t addend;

> -    int type;

> +    int addend  : 32;

> +    int rtype   : 16;

> +    int nlong   : 16;

> +    tcg_target_ulong data[];

>  } TCGLabelPoolData;

>


Seems a bit odd to use bitfields for 32 and 16 bit values, but whatever.
(My default reaction to bitfields is "be suspicious" :-))

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>


thanks
-- PMM
Alex Bennée Jan. 22, 2018, 7:15 p.m. UTC | #2 
Peter Maydell <peter.maydell@linaro.org> writes:

> On 17 January 2018 at 16:14, Richard Henderson

> <richard.henderson@linaro.org> wrote:

>> This will be required for storing vector constants.

>>

>> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

>> ---

>>  tcg/tcg-pool.inc.c | 115 +++++++++++++++++++++++++++++++++++++++++++----------

>>  1 file changed, 93 insertions(+), 22 deletions(-)

>>

>> diff --git a/tcg/tcg-pool.inc.c b/tcg/tcg-pool.inc.c

>> index 8a85131405..0f76e7bee3 100644

>> --- a/tcg/tcg-pool.inc.c

>> +++ b/tcg/tcg-pool.inc.c

>> @@ -22,39 +22,110 @@

>>

>>  typedef struct TCGLabelPoolData {

>>      struct TCGLabelPoolData *next;

>> -    tcg_target_ulong data;

>>      tcg_insn_unit *label;

>> -    intptr_t addend;

>> -    int type;

>> +    int addend  : 32;

>> +    int rtype   : 16;

>> +    int nlong   : 16;

>> +    tcg_target_ulong data[];

>>  } TCGLabelPoolData;

>>

>

> Seems a bit odd to use bitfields for 32 and 16 bit values, but whatever.

> (My default reaction to bitfields is "be suspicious" :-))


I'm guessing this is the same reason as the softfloat re-factor. By
manually forcing stuff into a bitfield the compiler does a better job of
passing multiple structure elements in a single register?

It would be nice if the compiler could spot this itself though.

>

> Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

>

> thanks

> -- PMM



--
Alex Bennée
Richard Henderson Jan. 22, 2018, 7:56 p.m. UTC | #3 
On 01/22/2018 11:15 AM, Alex Bennée wrote:
>>>  typedef struct TCGLabelPoolData {

>>>      struct TCGLabelPoolData *next;

>>> -    tcg_target_ulong data;

>>>      tcg_insn_unit *label;

>>> -    intptr_t addend;

>>> -    int type;

>>> +    int addend  : 32;

>>> +    int rtype   : 16;

>>> +    int nlong   : 16;

>>> +    tcg_target_ulong data[];

>>>  } TCGLabelPoolData;

>>>

>>

>> Seems a bit odd to use bitfields for 32 and 16 bit values, but whatever.

>> (My default reaction to bitfields is "be suspicious" :-))

> 

> I'm guessing this is the same reason as the softfloat re-factor. By

> manually forcing stuff into a bitfield the compiler does a better job of

> passing multiple structure elements in a single register?

> 

> It would be nice if the compiler could spot this itself though.


You're probably right that I could just use int16_t etc.


r~
diff mbox series

Patch

diff --git a/tcg/tcg-pool.inc.c b/tcg/tcg-pool.inc.c
index 8a85131405..0f76e7bee3 100644
--- a/tcg/tcg-pool.inc.c
+++ b/tcg/tcg-pool.inc.c
@@ -22,39 +22,110 @@ 
 
 typedef struct TCGLabelPoolData {
     struct TCGLabelPoolData *next;
-    tcg_target_ulong data;
     tcg_insn_unit *label;
-    intptr_t addend;
-    int type;
+    int addend  : 32;
+    int rtype   : 16;
+    int nlong   : 16;
+    tcg_target_ulong data[];
 } TCGLabelPoolData;
 
 
-static void new_pool_label(TCGContext *s, tcg_target_ulong data, int type,
-                           tcg_insn_unit *label, intptr_t addend)
+static TCGLabelPoolData *new_pool_alloc(TCGContext *s, int nlong, int rtype,
+                                        tcg_insn_unit *label, int addend)
 {
-    TCGLabelPoolData *n = tcg_malloc(sizeof(*n));
-    TCGLabelPoolData *i, **pp;
+    TCGLabelPoolData *n = tcg_malloc(sizeof(TCGLabelPoolData)
+                                     + sizeof(tcg_target_ulong) * nlong);
 
-    n->data = data;
     n->label = label;
-    n->type = type;
     n->addend = addend;
+    n->rtype = rtype;
+    n->nlong = nlong;
+    return n;
+}
+
+static void new_pool_insert(TCGContext *s, TCGLabelPoolData *n)
+{
+    TCGLabelPoolData *i, **pp;
+    int nlong = n->nlong;
 
     /* Insertion sort on the pool.  */
-    for (pp = &s->pool_labels; (i = *pp) && i->data < data; pp = &i->next) {
-        continue;
+    for (pp = &s->pool_labels; (i = *pp) != NULL; pp = &i->next) {
+        if (nlong > i->nlong) {
+            break;
+        }
+        if (nlong < i->nlong) {
+            continue;
+        }
+        if (memcmp(n->data, i->data, sizeof(tcg_target_ulong) * nlong) >= 0) {
+            break;
+        }
     }
     n->next = *pp;
     *pp = n;
 }
 
+/* The "usual" for generic integer code.  */
+static inline void new_pool_label(TCGContext *s, tcg_target_ulong d, int rtype,
+                                  tcg_insn_unit *label, int addend)
+{
+    TCGLabelPoolData *n = new_pool_alloc(s, 1, rtype, label, addend);
+    n->data[0] = d;
+    new_pool_insert(s, n);
+}
+
+/* For v64 or v128, depending on the host.  */
+static inline void new_pool_l2(TCGContext *s, int rtype, tcg_insn_unit *label,
+                               int addend, tcg_target_ulong d0,
+                               tcg_target_ulong d1)
+{
+    TCGLabelPoolData *n = new_pool_alloc(s, 2, rtype, label, addend);
+    n->data[0] = d0;
+    n->data[1] = d1;
+    new_pool_insert(s, n);
+}
+
+/* For v128 or v256, depending on the host.  */
+static inline void new_pool_l4(TCGContext *s, int rtype, tcg_insn_unit *label,
+                               int addend, tcg_target_ulong d0,
+                               tcg_target_ulong d1, tcg_target_ulong d2,
+                               tcg_target_ulong d3)
+{
+    TCGLabelPoolData *n = new_pool_alloc(s, 4, rtype, label, addend);
+    n->data[0] = d0;
+    n->data[1] = d1;
+    n->data[2] = d2;
+    n->data[3] = d3;
+    new_pool_insert(s, n);
+}
+
+/* For v256, for 32-bit host.  */
+static inline void new_pool_l8(TCGContext *s, int rtype, tcg_insn_unit *label,
+                               int addend, tcg_target_ulong d0,
+                               tcg_target_ulong d1, tcg_target_ulong d2,
+                               tcg_target_ulong d3, tcg_target_ulong d4,
+                               tcg_target_ulong d5, tcg_target_ulong d6,
+                               tcg_target_ulong d7)
+{
+    TCGLabelPoolData *n = new_pool_alloc(s, 8, rtype, label, addend);
+    n->data[0] = d0;
+    n->data[1] = d1;
+    n->data[2] = d2;
+    n->data[3] = d3;
+    n->data[4] = d4;
+    n->data[5] = d5;
+    n->data[6] = d6;
+    n->data[7] = d7;
+    new_pool_insert(s, n);
+}
+
 /* To be provided by cpu/tcg-target.inc.c.  */
 static void tcg_out_nop_fill(tcg_insn_unit *p, int count);
 
 static bool tcg_out_pool_finalize(TCGContext *s)
 {
     TCGLabelPoolData *p = s->pool_labels;
-    tcg_target_ulong d, *a;
+    TCGLabelPoolData *l = NULL;
+    void *a;
 
     if (p == NULL) {
         return true;
@@ -62,24 +133,24 @@  static bool tcg_out_pool_finalize(TCGContext *s)
 
     /* ??? Round up to qemu_icache_linesize, but then do not round
        again when allocating the next TranslationBlock structure.  */
-    a = (void *)ROUND_UP((uintptr_t)s->code_ptr, sizeof(tcg_target_ulong));
+    a = (void *)ROUND_UP((uintptr_t)s->code_ptr,
+                         sizeof(tcg_target_ulong) * p->nlong);
     tcg_out_nop_fill(s->code_ptr, (tcg_insn_unit *)a - s->code_ptr);
     s->data_gen_ptr = a;
 
-    /* Ensure the first comparison fails.  */
-    d = p->data + 1;
-
     for (; p != NULL; p = p->next) {
-        if (p->data != d) {
-            d = p->data;
-            if (unlikely((void *)a > s->code_gen_highwater)) {
+        size_t size = sizeof(tcg_target_ulong) * p->nlong;
+        if (!l || l->nlong != p->nlong || memcmp(l->data, p->data, size)) {
+            if (unlikely(a > s->code_gen_highwater)) {
                 return false;
             }
-            *a++ = d;
+            memcpy(a, p->data, size);
+            a += size;
+            l = p;
         }
-        patch_reloc(p->label, p->type, (intptr_t)(a - 1), p->addend);
+        patch_reloc(p->label, p->rtype, (intptr_t)a - size, p->addend);
     }
 
-    s->code_ptr = (void *)a;
+    s->code_ptr = a;
     return true;
 }