diff mbox series

AArch64: Fix PR103085

Message ID VE1PR08MB55999AB6A9F7E819F3F3C158838E9@VE1PR08MB5599.eurprd08.prod.outlook.com
State New
Headers show
Series AArch64: Fix PR103085 | expand

Commit Message

Wilco Dijkstra Nov. 5, 2021, 1:55 p.m. UTC 
The stack protector implementation hides symbols in a const unspec, which means
movdi/movsi patterns must always support const on symbol operands and explicitly
strip away the unspec. Do this for the recently added GOT alternatives. Add a
test to ensure stack-protector tests GOT accesses as well.

Passes bootstrap and regress. OK for commit?

2021-11-05  Wilco Dijkstra  <wdijkstr@arm.com>

        PR target/103085
        * config/aarch64/aarch64.c (aarch64_mov_operand_p): Strip the salt first.
        * config/aarch64/constraints.md: Support const in Usw.

        * gcc.target/aarch64/pr103085.c: New test
---

Comments

Richard Sandiford Nov. 5, 2021, 3:09 p.m. UTC | #1 
Wilco Dijkstra <Wilco.Dijkstra@arm.com> writes:
> The stack protector implementation hides symbols in a const unspec, which means
> movdi/movsi patterns must always support const on symbol operands and explicitly
> strip away the unspec. Do this for the recently added GOT alternatives. Add a
> test to ensure stack-protector tests GOT accesses as well.
>
> Passes bootstrap and regress. OK for commit?
>
> 2021-11-05  Wilco Dijkstra  <wdijkstr@arm.com>
>
>         PR target/103085
>         * config/aarch64/aarch64.c (aarch64_mov_operand_p): Strip the salt first.
>         * config/aarch64/constraints.md: Support const in Usw.
>
>         * gcc.target/aarch64/pr103085.c: New test

OK, thanks.

Richard

> ---
>
> diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
> index 430ea036a7be4da842fd08998923a3462457dbfd..39de231d8ac6d10362cdd2b48eb9bd9de60c6703 100644
> --- a/gcc/config/aarch64/aarch64.c
> +++ b/gcc/config/aarch64/aarch64.c
> @@ -20155,12 +20155,14 @@ aarch64_mov_operand_p (rtx x, machine_mode mode)
>        return aarch64_simd_valid_immediate (x, NULL);
>      }
>
> +  /* Remove UNSPEC_SALT_ADDR before checking symbol reference.  */
> +  x = strip_salt (x);
> +
>    /* GOT accesses are valid moves.  */
>    if (SYMBOL_REF_P (x)
>        && aarch64_classify_symbolic_expression (x) == SYMBOL_SMALL_GOT_4G)
>      return true;
>
> -  x = strip_salt (x);
>    if (SYMBOL_REF_P (x) && mode == DImode && CONSTANT_ADDRESS_P (x))
>      return true;
>
> diff --git a/gcc/config/aarch64/constraints.md b/gcc/config/aarch64/constraints.md
> index 70ca66070217d06f974b18f7690326bc329fed89..da5438e7ce254272eb10e9ac60d5367c46635e84 100644
> --- a/gcc/config/aarch64/constraints.md
> +++ b/gcc/config/aarch64/constraints.md
> @@ -152,10 +152,11 @@ (define_constraint "Usa"
>         (match_test "aarch64_symbolic_address_p (op)")
>         (match_test "aarch64_mov_operand_p (op, GET_MODE (op))")))
>
> +;; const is needed here to support UNSPEC_SALT_ADDR.
>  (define_constraint "Usw"
>    "@internal
>     A constraint that matches a small GOT access."
> -  (and (match_code "symbol_ref")
> +  (and (match_code "const,symbol_ref")
>         (match_test "aarch64_classify_symbolic_expression (op)
>                      == SYMBOL_SMALL_GOT_4G")))
>
> diff --git a/gcc/testsuite/gcc.target/aarch64/pr103085.c b/gcc/testsuite/gcc.target/aarch64/pr103085.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..dbc9c15b71f224b3c7dec0cca5655a31adc207f6
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/pr103085.c
> @@ -0,0 +1,11 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fstack-protector-strong -fPIC" } */
> +
> +void g(int*);
> +void
> +f (int x)
> +{
> +  int arr[10];
> +  g (arr);
> +}
> +
diff mbox series

Patch

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 430ea036a7be4da842fd08998923a3462457dbfd..39de231d8ac6d10362cdd2b48eb9bd9de60c6703 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -20155,12 +20155,14 @@  aarch64_mov_operand_p (rtx x, machine_mode mode)
       return aarch64_simd_valid_immediate (x, NULL);
     }
 
+  /* Remove UNSPEC_SALT_ADDR before checking symbol reference.  */
+  x = strip_salt (x);
+
   /* GOT accesses are valid moves.  */
   if (SYMBOL_REF_P (x)
       && aarch64_classify_symbolic_expression (x) == SYMBOL_SMALL_GOT_4G)
     return true;
 
-  x = strip_salt (x);
   if (SYMBOL_REF_P (x) && mode == DImode && CONSTANT_ADDRESS_P (x))
     return true;
 
diff --git a/gcc/config/aarch64/constraints.md b/gcc/config/aarch64/constraints.md
index 70ca66070217d06f974b18f7690326bc329fed89..da5438e7ce254272eb10e9ac60d5367c46635e84 100644
--- a/gcc/config/aarch64/constraints.md
+++ b/gcc/config/aarch64/constraints.md
@@ -152,10 +152,11 @@  (define_constraint "Usa"
        (match_test "aarch64_symbolic_address_p (op)")
        (match_test "aarch64_mov_operand_p (op, GET_MODE (op))")))
 
+;; const is needed here to support UNSPEC_SALT_ADDR.
 (define_constraint "Usw"
   "@internal
    A constraint that matches a small GOT access."
-  (and (match_code "symbol_ref")
+  (and (match_code "const,symbol_ref")
        (match_test "aarch64_classify_symbolic_expression (op)
 		     == SYMBOL_SMALL_GOT_4G")))
 
diff --git a/gcc/testsuite/gcc.target/aarch64/pr103085.c b/gcc/testsuite/gcc.target/aarch64/pr103085.c
new file mode 100644
index 0000000000000000000000000000000000000000..dbc9c15b71f224b3c7dec0cca5655a31adc207f6
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/pr103085.c
@@ -0,0 +1,11 @@ 
+/* { dg-do compile } */
+/* { dg-options "-O2 -fstack-protector-strong -fPIC" } */
+
+void g(int*);
+void
+f (int x)
+{
+  int arr[10];
+  g (arr);
+}
+