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[PATCH] Fix ix86_split_long_move collision handling with TLS (PR target/66470)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Uros Bizjak <ubizjak at gmail dot com>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Tue, 9 Jun 2015 13:57:39 +0200
- Subject: [PATCH] Fix ix86_split_long_move collision handling with TLS (PR target/66470)
- Authentication-results: sourceware.org; auth=none
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
As mentioned in the PR, when trying to split:
(insn 7 15 13 2 (set (reg:DI 0 ax [92])
(mem:DI (plus:SI (plus:SI (mult:SI (reg/v:SI 1 dx [orig:89 b ] [89])
(const_int 8 [0x8]))
(unspec:SI [
(const_int 0 [0])
] UNSPEC_TP))
(reg:SI 0 ax [91])) [1 a S8 A64])) rh1212265.i:2 85 {*movdi_internal}
(nil))
which has collisions == 2 (both ax and dx used on lhs and both
ax and dx used in the memory address), we generate invalid insn
- lea with %gs: or %fs: in it. This patch fixes it by using
normal lea instead (so remove the unspec UNSPEC_TP from the address
for lea) and duplicating the unspec UNSPEC_TP to all the memory loads.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for
trunk/5/4.9/4.8?
2015-06-09 Jakub Jelinek <jakub@redhat.com>
PR target/66470
* config/i386/i386.c (ix86_split_long_move): For collisions
involving direct tls segment refs, move the UNSPEC_TP out of
the address for lea, to each of the memory loads.
* gcc.dg/tls/pr66470.c: New test.
--- gcc/config/i386/i386.c.jj 2015-06-08 15:41:19.000000000 +0200
+++ gcc/config/i386/i386.c 2015-06-09 11:50:29.960859723 +0200
@@ -22866,7 +22866,7 @@ ix86_split_long_move (rtx operands[])
Do an lea to the last part and use only one colliding move. */
else if (collisions > 1)
{
- rtx base;
+ rtx base, addr, tls_base = NULL_RTX;
collisions = 1;
@@ -22877,10 +22877,45 @@ ix86_split_long_move (rtx operands[])
if (GET_MODE (base) != Pmode)
base = gen_rtx_REG (Pmode, REGNO (base));
- emit_insn (gen_rtx_SET (base, XEXP (part[1][0], 0)));
+ addr = XEXP (part[1][0], 0);
+ if (TARGET_TLS_DIRECT_SEG_REFS)
+ {
+ struct ix86_address parts;
+ int ok = ix86_decompose_address (addr, &parts);
+ gcc_assert (ok);
+ if (parts.seg == DEFAULT_TLS_SEG_REG)
+ {
+ /* It is not valid to use %gs: or %fs: in
+ lea though, so we need to remove it from the
+ address used for lea and add it to each individual
+ memory loads instead. */
+ addr = copy_rtx (addr);
+ rtx *x = &addr;
+ while (GET_CODE (*x) == PLUS)
+ {
+ for (i = 0; i < 2; i++)
+ if (GET_CODE (XEXP (*x, i)) == UNSPEC
+ && XINT (XEXP (*x, i), 1) == UNSPEC_TP)
+ {
+ tls_base = XEXP (*x, i);
+ *x = XEXP (*x, 1 - i);
+ break;
+ }
+ if (tls_base)
+ break;
+ x = &XEXP (*x, 0);
+ }
+ gcc_assert (tls_base);
+ }
+ }
+ emit_insn (gen_rtx_SET (base, addr));
+ if (tls_base)
+ base = gen_rtx_PLUS (GET_MODE (base), base, tls_base);
part[1][0] = replace_equiv_address (part[1][0], base);
for (i = 1; i < nparts; i++)
{
+ if (tls_base)
+ base = copy_rtx (base);
tmp = plus_constant (Pmode, base, UNITS_PER_WORD * i);
part[1][i] = replace_equiv_address (part[1][i], tmp);
}
--- gcc/testsuite/gcc.dg/tls/pr66470.c.jj 2015-06-09 11:59:05.543954781 +0200
+++ gcc/testsuite/gcc.dg/tls/pr66470.c 2015-06-09 11:58:43.000000000 +0200
@@ -0,0 +1,29 @@
+/* PR target/66470 */
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+/* { dg-require-effective-target tls } */
+
+extern __thread unsigned long long a[10];
+extern __thread struct S { int a, b; } b[10];
+
+unsigned long long
+foo (long x)
+{
+ return a[x];
+}
+
+struct S
+bar (long x)
+{
+ return b[x];
+}
+
+#ifdef __SIZEOF_INT128__
+extern __thread unsigned __int128 c[10];
+
+unsigned __int128
+baz (long x)
+{
+ return c[x];
+}
+#endif
Jakub