VAX: Define LEGITIMATE_PIC_OPERAND_P

The VAX ELF psABI does not permit the use of all hardware operand modes
for PIC symbol references due to the need to use PC-relative addressing
for symbols that end up local and the need to make references indirect
symbols that end up global.

Therefore symbols referred as immediates may only be used with the move
and push address (MOVA and PUSHA) instructions and their PC-relative
displacement address mode, as there is no genuine PC-relative immediate
available that all the other instructions would have to use.

Furthermore global symbol references must not have an offset applied,
which has to be added with a separate instruction, because there is no
support now for GOT entries for external `symbol+offset' references, so
any indirect GOT references made by the static linker from the original
direct symbol references must not have an addend applied.  Consequently
no addend is allowed even if a given external symbol turns out local,
for whatever reason, at the static link time.

Define the LEGITIMATE_PIC_OPERAND_P macro then, a corresponding function
and predicate to exclude the relevant expressions as required, and then
a constraint so that reloads are produced where needed, and use the new
facilities in the machine description, folding corresponding duplicated
patterns for local and external symbols together.  Rewrite predicates to
make use of the new function, rename them to match their sense and also
remove ones no longer used.

All this fixing an ICE like this:

during RTL pass: postreload
.../gcc/testsuite/gcc.c-torture/execute/20040709-2.c: In function 'testE':
.../gcc/testsuite/gcc.c-torture/execute/20040709-2.c:89:1: internal compiler error: in reload_combine_note_use, at postreload.c:1559
.../gcc/testsuite/gcc.c-torture/execute/20040709-2.c:96:65: note: in expansion of macro 'T'
0x10fe84cb reload_combine_note_use
	.../gcc/postreload.c:1559
0x10fe8857 reload_combine_note_use
	.../gcc/postreload.c:1621
0x10fe8303 reload_combine_note_use
	.../gcc/postreload.c:1517
0x10fe7c7b reload_combine
	.../gcc/postreload.c:1408
0x10fe3417 reload_cse_regs
	.../gcc/postreload.c:67
0x10feaf9f execute
	.../gcc/postreload.c:2358

due to the presence of a pseudo register post-reload:

(insn 435 228 229 13 (set (reg:SI 1 %r1)
        (mem/c:SI (reg/f:SI 341) [25 sE+12 S4 A8])) ".../gcc/testsuite/gcc.c-torture/execute/20040709-2.c":96:65 12 {movsi_2}
     (nil))

(due to the use of an offset `sE+12' symbol reference) and removing
these regressions:

FAIL: gcc.c-torture/execute/20040709-2.c   -O2  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-2.c   -O2  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-2.c   -O3 -fomit-frame-pointer -funroll-loops -fpeel-loops -ftracer -finline-functions  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-2.c   -O3 -fomit-frame-pointer -funroll-loops -fpeel-loops -ftracer -finline-functions  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-2.c   -O3 -g  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-2.c   -O3 -g  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-2.c   -Os  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-2.c   -Os  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-2.c   -O2 -flto -fno-use-linker-plugin -flto-partition=none  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-2.c   -O2 -flto -fno-use-linker-plugin -flto-partition=none  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-3.c   -O2  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-3.c   -O2  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-3.c   -O3 -g  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-3.c   -O3 -g  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-3.c   -Os  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-3.c   -Os  (test for excess errors)
FAIL: gcc.c-torture/execute/20040709-3.c   -O2 -flto -fno-use-linker-plugin -flto-partition=none  (internal compiler error)
FAIL: gcc.c-torture/execute/20040709-3.c   -O2 -flto -fno-use-linker-plugin -flto-partition=none  (test for excess errors)
FAIL: gcc.dg/torture/pr52028.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  (internal compiler error)
FAIL: gcc.dg/torture/pr52028.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  (test for excess errors)

	gcc/
	* config/vax/constraints.md (A): New constraint.
	* config/vax/predicates.md (external_symbolic_operand)
	(external_const_operand): Remove predicates.
	(local_symbolic_operand): Rename to...
	(pic_symbolic_operand): ... this, and rework.
	(external_memory_operand): Rename to...
	(non_pic_external_memory_operand): ... this, and rework.
	(illegal_blk_memory_operand, illegal_addsub_di_memory_operand):
	Update accordingly.
	* config/vax/vax-protos.h (vax_acceptable_pic_operand_p): New
	prototype.
	* config/vax/vax.c (vax_acceptable_pic_operand_p): New function.
	(vax_output_int_add): Update according to predicate rework.
	* config/vax/vax.h (LEGITIMATE_PIC_OPERAND_P): New macro.
	* config/vax/vax.md (pushlclsymreg, pushextsymreg): Fold
	together, and rename to...
	(*pushsymreg): ... this.  Use the `pic_symbolic_operand'
	predicate and the `A' constraint for the displacement operand.
	(movlclsymreg, movextsymreg): Fold together, and rename to...
	(*movsymreg): ... this.  Use the `pic_symbolic_operand'
	predicate and the `A' constraint for the displacement operand.
	(pushextsym, pushlclsym): Fold together, and rename to...
	(*pushsym): ... this.  Use the `pic_symbolic_operand' predicate
	and the `A' constraint for the displacement operand.
	(movextsym, movlclsym): Fold together, and rename to...
	(*movsym): ... this.  Use the `pic_symbolic_operand' predicate
	and the `A' constraint for the displacement operand.

diff --git a/gcc/config/vax/constraints.md b/gcc/config/vax/constraints.md
index b8262b6da6ff9f117743ef8350d897c96725201b..d4eddb82a666b31f55f8939a429dc52cd9c4c8e5 100644 (file)
--- a/gcc/config/vax/constraints.md
+++ b/gcc/config/vax/constraints.md
@@ -112,6 +112,10 @@
     (and (match_operand:DI 0 "memory_operand")
         (not (match_operand:DI 0 "illegal_addsub_di_memory_operand" ""))))
 
+(define_constraint "A"
+    "@internal An integer constant suitable for address load operations."
+  (match_test ("CONSTANT_P (op) && pic_symbolic_operand (op, mode)")))
+
 (define_constraint "T"
     "@internal satisfies CONSTANT_P and, if pic is enabled, is not a SYMBOL_REF, LABEL_REF, or CONST."
   (and (match_test ("CONSTANT_P (op)"))

diff --git a/gcc/config/vax/predicates.md b/gcc/config/vax/predicates.md
index 7eefc605e98d5bc96deb383c589ab1e4c8dc78e7..93e91e499a6755c82b07646073642090c0bff821 100644 (file)
--- a/gcc/config/vax/predicates.md
+++ b/gcc/config/vax/predicates.md
@@ -23,33 +23,17 @@
 (define_predicate "symbolic_operand"
   (match_code "const,symbol_ref,label_ref"))
 
-(define_predicate "local_symbolic_operand"
-  (match_code "const,symbol_ref,label_ref")
-{
-  if (GET_CODE (op) == LABEL_REF)
-    return 1;
-  if (GET_CODE (op) == SYMBOL_REF)
-    return !flag_pic || SYMBOL_REF_LOCAL_P (op);
-  if (GET_CODE (XEXP (XEXP (op, 0), 0)) == LABEL_REF)
-    return 1;
-  return !flag_pic || SYMBOL_REF_LOCAL_P (XEXP (XEXP (op, 0), 0));
-})
-
-(define_predicate "external_symbolic_operand"
-  (and (match_code "symbol_ref")
-       (not (match_operand 0 "local_symbolic_operand" ""))))
-
-(define_predicate "external_const_operand"
-  (and (match_code "const")
-       (match_test "GET_CODE (XEXP (XEXP (op, 0), 0)) == SYMBOL_REF
-                   && !SYMBOL_REF_LOCAL_P (XEXP (XEXP (op, 0), 0))")))
+(define_predicate "pic_symbolic_operand"
+  (and (match_code "const,symbol_ref,label_ref")
+       (match_test "!flag_pic
+                   || vax_acceptable_pic_operand_p (op, false, true)")))
 
 (define_predicate "nonsymbolic_operand"
   (and (ior (match_test "!flag_pic")
            (not (match_operand 0 "symbolic_operand")))
        (match_operand 0 "general_operand" "")))
 
-(define_predicate "external_memory_operand"
+(define_predicate "non_pic_external_memory_operand"
    (match_code "mem")
 {
   rtx addr = XEXP (op, 0);
@@ -61,8 +45,8 @@
     addr = XEXP (addr, 0);
   if (GET_CODE (addr) == PLUS)
     addr = XEXP (addr, 1);
-  return external_symbolic_operand (addr, SImode)
-        || external_const_operand (addr, SImode);
+  return (symbolic_operand (addr, SImode)
+         && !vax_acceptable_pic_operand_p (addr, true, true));
 })
 
 (define_predicate "indirect_memory_operand"
@@ -87,7 +71,7 @@
 (define_predicate "illegal_blk_memory_operand"
    (and (match_code "mem")
        (ior (and (match_test "flag_pic")
-                 (match_operand 0 "external_memory_operand" ""))
+                 (match_operand 0 "non_pic_external_memory_operand" ""))
             (ior (match_operand 0 "indexed_memory_operand" "")
                  (ior (match_operand 0 "indirect_memory_operand" "")
                       (match_test "GET_CODE (XEXP (op, 0)) == PRE_DEC"))))))
@@ -95,7 +79,7 @@
 (define_predicate "illegal_addsub_di_memory_operand"
    (and (match_code "mem")
        (ior (and (match_test "flag_pic")
-                 (match_operand 0 "external_memory_operand" ""))
+                 (match_operand 0 "non_pic_external_memory_operand" ""))
             (ior (match_operand 0 "indexed_memory_operand" "")
                  (ior (match_operand 0 "indirect_memory_operand" "")
                       (match_test "GET_CODE (XEXP (op, 0)) == PRE_DEC"))))))

diff --git a/gcc/config/vax/vax-protos.h b/gcc/config/vax/vax-protos.h
index cda2544f7d533e30b5db32698104a0af0ea5f9de..454d35e3383a6a6095b52ad851c6a5df9072e466 100644 (file)
--- a/gcc/config/vax/vax-protos.h
+++ b/gcc/config/vax/vax-protos.h
@@ -21,6 +21,7 @@ extern bool legitimate_constant_address_p (rtx);
 extern void vax_expand_prologue (void);
 
 #ifdef RTX_CODE
+extern bool vax_acceptable_pic_operand_p (rtx, bool, bool);
 extern const char *cond_name (rtx);
 extern bool adjacent_operands_p (rtx, rtx, machine_mode);
 extern const char *rev_cond_name (rtx);

diff --git a/gcc/config/vax/vax.c b/gcc/config/vax/vax.c
index 0b3b76ed6da8241d1f909e3ad7d8eabc8d55967f..37f5dadc74cadf0d6d586ae9d55023ec139217e1 100644 (file)
--- a/gcc/config/vax/vax.c
+++ b/gcc/config/vax/vax.c
@@ -1033,6 +1033,39 @@ vax_rtx_costs (rtx x, machine_mode mode, int outer_code,
   return true;
 }
 \f
+/* With ELF we do not support GOT entries for external `symbol+offset'
+   references, so do not accept external symbol references if an offset
+   is to be added.  Do not accept external symbol references at all if
+   LOCAL_P is set.  This is for cases where making a reference indirect
+   would make it invalid.  Do not accept any kind of symbols if SYMBOL_P
+   is clear.  This is for situations where the a reference is used as an
+   immediate value for operations other than address loads (MOVA/PUSHA),
+   as those operations do not support PC-relative immediates.  */
+
+bool
+vax_acceptable_pic_operand_p (rtx x ATTRIBUTE_UNUSED,
+                             bool local_p ATTRIBUTE_UNUSED,
+                             bool symbol_p ATTRIBUTE_UNUSED)
+{
+#ifdef NO_EXTERNAL_INDIRECT_ADDRESS
+  if (GET_CODE (x) == CONST && GET_CODE (XEXP (x, 0)) == PLUS)
+    {
+      x = XEXP (XEXP (x, 0), 0);
+      local_p = true;
+    }
+  switch (GET_CODE (x))
+    {
+    case SYMBOL_REF:
+      return symbol_p && !(local_p && !SYMBOL_REF_LOCAL_P (x));
+    case LABEL_REF:
+      return symbol_p && !(local_p && LABEL_REF_NONLOCAL_P (x));
+    default:
+      break;
+    }
+#endif
+  return true;
+}
+\f
 /* Output code to add DELTA to the first argument, and then jump to FUNCTION.
    Used for C++ multiple inheritance.
        .mask   ^m<r2,r3,r4,r5,r6,r7,r8,r9,r10,r11>  #conservative entry mask
@@ -1370,8 +1403,10 @@ vax_output_int_add (rtx_insn *insn, rtx *operands, machine_mode mode)
          {
            gcc_assert (rtx_equal_p (operands[0], operands[1]));
 #ifdef NO_EXTERNAL_INDIRECT_ADDRESS
-           gcc_assert (!flag_pic || !external_memory_operand (low[2], SImode));
-           gcc_assert (!flag_pic || !external_memory_operand (low[0], SImode));
+           gcc_assert (!flag_pic
+                       || !non_pic_external_memory_operand (low[2], SImode));
+           gcc_assert (!flag_pic
+                       || !non_pic_external_memory_operand (low[0], SImode));
 #endif
 
            /* No reason to add a 0 to the low part and thus no carry, so just

diff --git a/gcc/config/vax/vax.h b/gcc/config/vax/vax.h
index c1d0171d94da15750225aeaf766b00d492cf080f..146b0a6e2b2db935b15c5015e69b0bb70603a5ce 100644 (file)
--- a/gcc/config/vax/vax.h
+++ b/gcc/config/vax/vax.h
@@ -442,6 +442,11 @@ enum reg_class { NO_REGS, ALL_REGS, LIM_REG_CLASSES };
    of a shift count.  */
 /* #define SHIFT_COUNT_TRUNCATED */
 
+/* We need to reject symbol references in PIC code except for address
+   loads, handled elsewhere.  */
+#define LEGITIMATE_PIC_OPERAND_P(x)    \
+  vax_acceptable_pic_operand_p ((x), false, false)
+
 /* Specify the machine mode that pointers have.
    After generation of rtl, the compiler makes no further distinction
    between pointers and any other objects of this machine mode.  */

diff --git a/gcc/config/vax/vax.md b/gcc/config/vax/vax.md
index e3018a0ee06ccbc9cebf19e5901fc910d327d997..e6b217fd0d73f685518e5cee027df186468e9d4b 100644 (file)
--- a/gcc/config/vax/vax.md
+++ b/gcc/config/vax/vax.md
@@ -338,34 +338,6 @@
    add<VAXfp:fsfx>2 %1,%0
    add<VAXfp:fsfx>3 %1,%2,%0")
 
-(define_insn "pushlclsymreg"
-  [(set (match_operand:SI 0 "push_operand" "=g")
-       (plus:SI (match_operand:SI 1 "register_operand" "%r")
-                (match_operand:SI 2 "local_symbolic_operand" "i")))]
-  "flag_pic"
-  "pushab %a2[%1]")
-
-(define_insn "pushextsymreg"
-  [(set (match_operand:SI 0 "push_operand" "=g")
-       (plus:SI (match_operand:SI 1 "register_operand" "%r")
-                (match_operand:SI 2 "external_symbolic_operand" "i")))]
-  "flag_pic"
-  "pushab %a2[%1]")
-
-(define_insn "movlclsymreg"
-  [(set (match_operand:SI 0 "nonimmediate_operand" "=g")
-       (plus:SI (match_operand:SI 1 "register_operand" "%r")
-                (match_operand:SI 2 "local_symbolic_operand" "i")))]
-  "flag_pic"
-  "movab %a2[%1],%0")
-
-(define_insn "movextsymreg"
-  [(set (match_operand:SI 0 "nonimmediate_operand" "=g")
-       (plus:SI (match_operand:SI 1 "register_operand" "%r")
-                (match_operand:SI 2 "external_symbolic_operand" "i")))]
-  "flag_pic"
-  "movab %a2[%1],%0")
-
 (define_insn "add<mode>3"
   [(set (match_operand:VAXint 0 "nonimmediate_operand" "=g")
        (plus:VAXint (match_operand:VAXint 1 "general_operand" "nrmT")
@@ -1525,29 +1497,31 @@
   ""
   "casel %0,$0,%1")
 \f
-(define_insn "pushextsym"
+(define_insn "*pushsym"
   [(set (match_operand:SI 0 "push_operand" "=g")
-       (match_operand:SI 1 "external_symbolic_operand" "i"))]
+       (match_operand:SI 1 "pic_symbolic_operand" "A"))]
   ""
   "pushab %a1")
 
-(define_insn "movextsym"
+(define_insn "*movsym"
   [(set (match_operand:SI 0 "nonimmediate_operand" "=g")
-       (match_operand:SI 1 "external_symbolic_operand" "i"))]
+       (match_operand:SI 1 "pic_symbolic_operand" "A"))]
   ""
   "movab %a1,%0")
 
-(define_insn "pushlclsym"
+(define_insn "*pushsymreg"
   [(set (match_operand:SI 0 "push_operand" "=g")
-       (match_operand:SI 1 "local_symbolic_operand" "i"))]
-  ""
-  "pushab %a1")
+       (plus:SI (match_operand:SI 1 "register_operand" "%r")
+                (match_operand:SI 2 "pic_symbolic_operand" "A")))]
+  "flag_pic"
+  "pushab %a2[%1]")
 
-(define_insn "movlclsym"
+(define_insn "*movsymreg"
   [(set (match_operand:SI 0 "nonimmediate_operand" "=g")
-       (match_operand:SI 1 "local_symbolic_operand" "i"))]
-  ""
-  "movab %a1,%0")
+       (plus:SI (match_operand:SI 1 "register_operand" "%r")
+                (match_operand:SI 2 "pic_symbolic_operand" "A")))]
+  "flag_pic"
+  "movab %a2[%1],%0")
 \f
 ;;- load or push effective address
 ;; These come after the move and add/sub patterns