[PATCH][AArch64][GCC 5] Backport Work around for PR target/64971

[Kyrill Tkachov]

Hi all,

I'd like to backport this fix for an ILP32 ICE. This was a simple band-aid 
proposed by Andrew
that is self-contained and doesn't touch non-ILP32 or non-aarch64 code so it 
should be pretty safe
to backport. It has been in trunk and GCC 6 for quite some time without issues 
until Renlin's patch at r235282
fixed the midend issue [1].

Bootstrapped and tested on GCC 5 on aarch64-none-linux-gnu.
Is this patch ok for the branch?

Thanks,
Kyrill

[1] https://gcc.gnu.org/ml/gcc-patches/2016-08/msg00332.html

2016-08-26  Kyrylo Tkachov  <kyrylo.tkac...@arm.com>

    Backport from mainline
    2016-04-20  Andrew Pinski  <apin...@cavium.com>
                Kyrylo Tkachov  <kyrylo.tkac...@arm.com>

    PR target/64971
    * config/aarch64/aarch64.md (sibcall): Force call
    address to be DImode for ILP32.
    (sibcall_value): Likewise.


    PR target/64971
   * gcc.c-torture/compile/pr37433 
<https://gcc.gnu.org/bugzilla/show_bug.cgi?id=37433>-1.c: New testcase.

diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md
index 116fd89102c98c5e1816998ce56cbc4d87525e97..501ae4481451b1730233eb4dfaca2a66a5b1c2ae 100644
--- a/gcc/config/aarch64/aarch64.md
+++ b/gcc/config/aarch64/aarch64.md
@@ -687,6 +687,13 @@ (define_expand "sibcall"
        && (GET_CODE (XEXP (operands[0], 0)) != SYMBOL_REF))
      XEXP (operands[0], 0) = force_reg (Pmode, XEXP (operands[0], 0));
 
+    /* This is a band-aid.  An SImode symbol reference is sometimes generated
+       by expand_expr_addr_expr.  See PR 64971.  */
+    if (TARGET_ILP32
+	&& GET_CODE (XEXP (operands[0], 0)) == SYMBOL_REF
+	&& GET_MODE (XEXP (operands[0], 0)) == SImode)
+      XEXP (operands[0], 0) = convert_memory_address (Pmode,
+						      XEXP (operands[0], 0));
     if (operands[2] == NULL_RTX)
       operands[2] = const0_rtx;
 
@@ -717,6 +724,14 @@ (define_expand "sibcall_value"
        && (GET_CODE (XEXP (operands[1], 0)) != SYMBOL_REF))
      XEXP (operands[1], 0) = force_reg (Pmode, XEXP (operands[1], 0));
 
+    /* This is a band-aid.  An SImode symbol reference is sometimes generated
+       by expand_expr_addr_expr.  See PR 64971.  */
+    if (TARGET_ILP32
+	&& GET_CODE (XEXP (operands[1], 0)) == SYMBOL_REF
+	&& GET_MODE (XEXP (operands[1], 0)) == SImode)
+      XEXP (operands[1], 0) = convert_memory_address (Pmode,
+						      XEXP (operands[1], 0));
+
     if (operands[3] == NULL_RTX)
       operands[3] = const0_rtx;
 
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr37433-1.c b/gcc/testsuite/gcc.c-torture/compile/pr37433-1.c
new file mode 100644
index 0000000000000000000000000000000000000000..c69e9692eb0229154676fc088c41741fa30f1871
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr37433-1.c
@@ -0,0 +1,13 @@
+void
+regex_subst (void)
+{
+  const void *subst = "";
+  (*(void (*)(int))subst) (0);
+}
+
+void
+foobar (void)
+{
+  int x;
+  (*(void (*)(void))&x) ();
+}