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[PATCH] Delegitimize TLS local-exec accesses on i?86/x86_64 (PR target/45870)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Uros Bizjak <ubizjak at gmail dot com>, Richard Henderson <rth at redhat dot com>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Fri, 8 Oct 2010 21:31:41 +0200
- Subject: [PATCH] Delegitimize TLS local-exec accesses on i?86/x86_64 (PR target/45870)
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
This patch delegitimizes TLS local-exec mode accesses, if
both UNSPEC_TP and UNSPEC_NTPOFF is present in the address.
On the attached testcase it gets rid of the --enable-checking=yes
notes about non-delegitimized UNSPECs in debug info output.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2010-10-08 Jakub Jelinek <jakub@redhat.com>
PR target/45870
* config/i386/i386.c (ix86_delegitimize_tls_address): New function.
(ix86_delegitimize_address): Use it.
* gcc.dg/tls/pr45870.c: New test.
--- gcc/config/i386/i386.c.jj 2010-10-07 19:45:19.000000000 +0200
+++ gcc/config/i386/i386.c 2010-10-07 22:26:01.000000000 +0200
@@ -12305,6 +12305,49 @@ ix86_pic_register_p (rtx x)
return REG_P (x) && REGNO (x) == PIC_OFFSET_TABLE_REGNUM;
}
+/* Helper function for ix86_delegitimize_address.
+ Attempt to delegitimize TLS local-exec accesses. */
+
+static rtx
+ix86_delegitimize_tls_address (rtx orig_x)
+{
+ rtx x = orig_x, unspec;
+ struct ix86_address addr;
+
+ if (!TARGET_TLS_DIRECT_SEG_REFS)
+ return orig_x;
+ if (MEM_P (x))
+ x = XEXP (x, 0);
+ if (GET_CODE (x) != PLUS || GET_MODE (x) != Pmode)
+ return orig_x;
+ if (ix86_decompose_address (x, &addr) == 0
+ || addr.seg != (TARGET_64BIT ? SEG_FS : SEG_GS)
+ || addr.disp == NULL_RTX
+ || GET_CODE (addr.disp) != CONST)
+ return orig_x;
+ unspec = XEXP (addr.disp, 0);
+ if (GET_CODE (unspec) == PLUS && CONST_INT_P (XEXP (unspec, 1)))
+ unspec = XEXP (unspec, 0);
+ if (GET_CODE (unspec) != UNSPEC || XINT (unspec, 1) != UNSPEC_NTPOFF)
+ return orig_x;
+ x = XVECEXP (unspec, 0, 0);
+ gcc_assert (GET_CODE (x) == SYMBOL_REF);
+ if (unspec != XEXP (addr.disp, 0))
+ x = gen_rtx_PLUS (Pmode, x, XEXP (XEXP (addr.disp, 0), 1));
+ if (addr.index)
+ {
+ rtx idx = addr.index;
+ if (addr.scale != 1)
+ idx = gen_rtx_MULT (Pmode, idx, GEN_INT (addr.scale));
+ x = gen_rtx_PLUS (Pmode, idx, x);
+ }
+ if (addr.base)
+ x = gen_rtx_PLUS (Pmode, addr.base, x);
+ if (MEM_P (orig_x))
+ x = replace_equiv_address_nv (orig_x, x);
+ return x;
+}
+
/* In the name of slightly smaller debug output, and to cater to
general assembler lossage, recognize PIC+GOTOFF and turn it back
into a direct symbol reference.
@@ -12340,7 +12383,7 @@ ix86_delegitimize_address (rtx x)
|| GET_CODE (XEXP (x, 0)) != UNSPEC
|| XINT (XEXP (x, 0), 1) != UNSPEC_GOTPCREL
|| !MEM_P (orig_x))
- return orig_x;
+ return ix86_delegitimize_tls_address (orig_x);
x = XVECEXP (XEXP (x, 0), 0, 0);
if (GET_MODE (orig_x) != Pmode)
return simplify_gen_subreg (GET_MODE (orig_x), x, Pmode, 0);
@@ -12349,7 +12392,7 @@ ix86_delegitimize_address (rtx x)
if (GET_CODE (x) != PLUS
|| GET_CODE (XEXP (x, 1)) != CONST)
- return orig_x;
+ return ix86_delegitimize_tls_address (orig_x);
if (ix86_pic_register_p (XEXP (x, 0)))
/* %ebx + GOT/GOTOFF */
@@ -12389,7 +12432,7 @@ ix86_delegitimize_address (rtx x)
result = XVECEXP (x, 0, 0);
if (! result)
- return orig_x;
+ return ix86_delegitimize_tls_address (orig_x);
if (const_addend)
result = gen_rtx_CONST (Pmode, gen_rtx_PLUS (Pmode, result, const_addend));
--- gcc/testsuite/gcc.dg/tls/pr45870.c.jj 2010-10-07 22:19:18.000000000 +0200
+++ gcc/testsuite/gcc.dg/tls/pr45870.c 2010-10-07 22:19:07.000000000 +0200
@@ -0,0 +1,21 @@
+/* PR target/45870 */
+/* { dg-do compile } */
+/* { dg-options "-g -O" } */
+/* { dg-require-effective-target tls } */
+
+__thread int v[30];
+int bar (void);
+
+int
+foo (int x, int y, int z)
+{
+ int a, b = z, c;
+ while (b > 0)
+ {
+ c = (bar () % 3);
+ a = v[x];
+ if (x < y)
+ for (;;);
+ b += a;
+ }
+}
Jakub