Hi all,
This is a reimplementation of Windows Thread Local Storage, rewritten to
support native thread local access on Windows, which had previous been using
emulated thread local storage mechanisms. Note that due to issues on my end, I
was unable to regenerate configure no matter what I tried. I do not have write
access to gcc, and will need help with committing this once the green light is
given (Although approval was already given by MINGW maintainers in the relevant
bug at https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80881 and in private
communication)
best regards,
Julian
gcc\ChangeLog:
* config/i386/i386.cc (ix86_legitimate_constant_p): Handle new UNSPEC
(legitimate_pic_operand_p): Handle new UNSPEC
(legitimate_pic_address_disp_p): Handle new UNSPEC
(ix86_legitimate_address_p): Handle new UNSPEC
(ix86_tls_index_symbol): New symbol
(ix86_tls_index): Handle creation of _tls_index symbol
(legitimize_tls_address): Create thread local access sequence
(output_pic_addr_const): Handle new UNSPEC
(i386_output_dwarf_dtprel): Handle new UNSPEC
(i386_asm_output_addr_const_extra): Handle new UNSPEC
* config/i386/i386.h (TARGET_WIN32_TLS): Define
* config/i386/i386.md: New UNSPEC
* config/i386/predicates.md: Handle new UNSPEC
* config/mingw/mingw32.h (TARGET_WIN32_TLS): Define
(TARGET_ASM_SELECT_SECTION): Define
(DEFAULT_TLS_SEG_REG): Define
* config/mingw/winnt.cc (mingw_pe_select_section): Handle TLS section
(mingw_pe_unique_section): Select TLS section
* config/mingw/winnt.h (mingw_pe_select_section): Declare
* configure.ac: New check for broken linker thread local support
>From 05d4491d862a16426f2a0986e7f3598714615f93 Mon Sep 17 00:00:00 2001
From: Julian Waters <tanksherma...@gmail.com>
Date: Tue, 15 Oct 2024 20:56:22 +0800
Subject: [PATCH] Implement Windows TLS
Signed-off-by: Julian Waters <tanksherma...@gmail.com>
---
gcc/config/i386/i386.cc | 61 ++++++++++++++++++++++++++++++++++-
gcc/config/i386/i386.h | 1 +
gcc/config/i386/i386.md | 1 +
gcc/config/i386/predicates.md | 1 +
gcc/config/mingw/mingw32.h | 9 ++++++
gcc/config/mingw/winnt.cc | 14 ++++++++
gcc/config/mingw/winnt.h | 1 +
gcc/configure.ac | 29 +++++++++++++++++
8 files changed, 116 insertions(+), 1 deletion(-)
diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
index 473e4cbf10e..304189bd947 100644
--- a/gcc/config/i386/i386.cc
+++ b/gcc/config/i386/i386.cc
@@ -11170,6 +11170,9 @@ ix86_legitimate_constant_p (machine_mode mode, rtx x)
x = XVECEXP (x, 0, 0);
return (GET_CODE (x) == SYMBOL_REF
&& SYMBOL_REF_TLS_MODEL (x) == TLS_MODEL_LOCAL_DYNAMIC);
+ case UNSPEC_SECREL32:
+ x = XVECEXP (x, 0, 0);
+ return GET_CODE (x) == SYMBOL_REF;
default:
return false;
}
@@ -11306,6 +11309,9 @@ legitimate_pic_operand_p (rtx x)
x = XVECEXP (inner, 0, 0);
return (GET_CODE (x) == SYMBOL_REF
&& SYMBOL_REF_TLS_MODEL (x) == TLS_MODEL_LOCAL_EXEC);
+ case UNSPEC_SECREL32:
+ x = XVECEXP (inner, 0, 0);
+ return GET_CODE (x) == SYMBOL_REF;
case UNSPEC_MACHOPIC_OFFSET:
return legitimate_pic_address_disp_p (x);
default:
@@ -11486,6 +11492,9 @@ legitimate_pic_address_disp_p (rtx disp)
disp = XVECEXP (disp, 0, 0);
return (GET_CODE (disp) == SYMBOL_REF
&& SYMBOL_REF_TLS_MODEL (disp) == TLS_MODEL_LOCAL_DYNAMIC);
+ case UNSPEC_SECREL32:
+ disp = XVECEXP (disp, 0, 0);
+ return GET_CODE (disp) == SYMBOL_REF;
}
return false;
@@ -11763,6 +11772,7 @@ ix86_legitimate_address_p (machine_mode, rtx addr, bool
strict,
case UNSPEC_INDNTPOFF:
case UNSPEC_NTPOFF:
case UNSPEC_DTPOFF:
+ case UNSPEC_SECREL32:
break;
default:
@@ -11788,7 +11798,8 @@ ix86_legitimate_address_p (machine_mode, rtx addr, bool
strict,
|| GET_CODE (XEXP (XEXP (disp, 0), 0)) != UNSPEC
|| !CONST_INT_P (XEXP (XEXP (disp, 0), 1))
|| (XINT (XEXP (XEXP (disp, 0), 0), 1) != UNSPEC_DTPOFF
- && XINT (XEXP (XEXP (disp, 0), 0), 1) != UNSPEC_NTPOFF))
+ && XINT (XEXP (XEXP (disp, 0), 0), 1) != UNSPEC_NTPOFF
+ && XINT (XEXP (XEXP (disp, 0), 0), 1) != UNSPEC_SECREL32))
/* Non-constant pic memory reference. */
return false;
}
@@ -12112,6 +12123,22 @@ get_thread_pointer (machine_mode tp_mode, bool to_reg)
return tp;
}
+/* Construct the SYMBOL_REF for the _tls_index symbol. */
+
+static GTY(()) rtx ix86_tls_index_symbol;
+
+static rtx
+ix86_tls_index (void)
+{
+ if (!ix86_tls_index_symbol)
+ ix86_tls_index_symbol = gen_rtx_SYMBOL_REF (SImode, "_tls_index");
+
+ if (flag_pic)
+ return gen_rtx_CONST (Pmode, gen_rtx_UNSPEC (Pmode, gen_rtvec (1,
ix86_tls_index_symbol), UNSPEC_PCREL));
+ else
+ return ix86_tls_index_symbol;
+}
+
/* Construct the SYMBOL_REF for the tls_get_addr function. */
static GTY(()) rtx ix86_tls_symbol;
@@ -12170,6 +12197,26 @@ legitimize_tls_address (rtx x, enum tls_model model,
bool for_mov)
machine_mode tp_mode = Pmode;
int type;
+#if TARGET_WIN32_TLS
+ off = gen_const_mem (SImode, ix86_tls_index ());
+ set_mem_alias_set (off, GOT_ALIAS_SET);
+
+ tp = gen_const_mem (Pmode, GEN_INT (TARGET_64BIT ? 88 : 44));
+ set_mem_addr_space (tp, DEFAULT_TLS_SEG_REG);
+
+ if (TARGET_64BIT)
+ off = convert_to_mode (Pmode, off, 1);
+
+ base = force_reg (Pmode, off);
+ tp = copy_to_mode_reg (Pmode, tp);
+
+ tp = gen_const_mem (Pmode, gen_rtx_PLUS (Pmode, tp, gen_rtx_MULT (Pmode,
base, GEN_INT (UNITS_PER_WORD))));
+ set_mem_alias_set (tp, GOT_ALIAS_SET);
+
+ base = force_reg (Pmode, tp);
+
+ return gen_rtx_PLUS (Pmode, base, gen_rtx_CONST (Pmode, gen_rtx_UNSPEC
(SImode, gen_rtvec (1, x), UNSPEC_SECREL32)));
+#else
/* Fall back to global dynamic model if tool chain cannot support local
dynamic. */
if (TARGET_SUN_TLS && !TARGET_64BIT
@@ -12403,6 +12450,7 @@ legitimize_tls_address (rtx x, enum tls_model model,
bool for_mov)
}
return dest;
+#endif
}
/* Return true if the TLS address requires insn using integer registers.
@@ -12872,6 +12920,9 @@ output_pic_addr_const (FILE *file, rtx x, int code)
case UNSPEC_INDNTPOFF:
fputs ("@indntpoff", file);
break;
+ case UNSPEC_SECREL32:
+ fputs ("@secrel32", file);
+ break;
#if TARGET_MACHO
case UNSPEC_MACHOPIC_OFFSET:
putc ('-', file);
@@ -12897,7 +12948,11 @@ i386_output_dwarf_dtprel (FILE *file, int size, rtx x)
{
fputs (ASM_LONG, file);
output_addr_const (file, x);
+#if TARGET_WIN32_TLS
+ fputs ("@secrel32", file);
+#else
fputs ("@dtpoff", file);
+#endif
switch (size)
{
case 4:
@@ -14650,6 +14705,10 @@ i386_asm_output_addr_const_extra (FILE *file, rtx x)
output_addr_const (file, op);
fputs ("@indntpoff", file);
break;
+ case UNSPEC_SECREL32:
+ output_addr_const (file, op);
+ fputs ("@secrel32", file);
+ break;
#if TARGET_MACHO
case UNSPEC_MACHOPIC_OFFSET:
output_addr_const (file, op);
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 51934400951..a10a368a5f7 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -510,6 +510,7 @@ extern unsigned char ix86_prefetch_sse;
#define TARGET_GNU2_TLS (ix86_tls_dialect == TLS_DIALECT_GNU2)
#define TARGET_ANY_GNU_TLS (TARGET_GNU_TLS || TARGET_GNU2_TLS)
#define TARGET_SUN_TLS 0
+#define TARGET_WIN32_TLS 0
#ifndef TARGET_64BIT_DEFAULT
#define TARGET_64BIT_DEFAULT 0
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index effab299349..865bf29d853 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -79,6 +79,7 @@
UNSPEC_MACHOPIC_OFFSET
UNSPEC_PCREL
UNSPEC_SIZEOF
+ UNSPEC_SECREL32
;; Prologue support
UNSPEC_STACK_ALLOC
diff --git a/gcc/config/i386/predicates.md b/gcc/config/i386/predicates.md
index 053312bbe27..d83b27355cc 100644
--- a/gcc/config/i386/predicates.md
+++ b/gcc/config/i386/predicates.md
@@ -218,6 +218,7 @@
case UNSPEC_DTPOFF:
case UNSPEC_GOTNTPOFF:
case UNSPEC_NTPOFF:
+ case UNSPEC_SECREL32:
return true;
default:
break;
diff --git a/gcc/config/mingw/mingw32.h b/gcc/config/mingw/mingw32.h
index 0dfe8e995b6..251271901a3 100644
--- a/gcc/config/mingw/mingw32.h
+++ b/gcc/config/mingw/mingw32.h
@@ -308,6 +308,15 @@ do {
\
#undef TARGET_N_FORMAT_TYPES
#define TARGET_N_FORMAT_TYPES 3
+#undef TARGET_WIN32_TLS
+#define TARGET_WIN32_TLS 1
+
+#undef TARGET_ASM_SELECT_SECTION
+#define TARGET_ASM_SELECT_SECTION mingw_pe_select_section
+
+#undef DEFAULT_TLS_SEG_REG
+#define DEFAULT_TLS_SEG_REG (TARGET_64BIT ? ADDR_SPACE_SEG_GS :
ADDR_SPACE_SEG_FS)
+
#define HAVE_ENABLE_EXECUTE_STACK
#undef CHECK_EXECUTE_STACK_ENABLED
#define CHECK_EXECUTE_STACK_ENABLED flag_setstackexecutable
diff --git a/gcc/config/mingw/winnt.cc b/gcc/config/mingw/winnt.cc
index 9d433daaf5a..8453965f625 100644
--- a/gcc/config/mingw/winnt.cc
+++ b/gcc/config/mingw/winnt.cc
@@ -392,6 +392,15 @@ i386_pe_strip_name_encoding_full (const char *str)
return name;
}
+section *
+mingw_pe_select_section (tree decl, int reloc, unsigned HOST_WIDE_INT align)
+{
+ if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
+ return get_named_section (decl, ".tls$", reloc);
+ else
+ return default_select_section (decl, reloc, align);
+}
+
void
mingw_pe_unique_section (tree decl, int reloc)
{
@@ -416,6 +425,8 @@ mingw_pe_unique_section (tree decl, int reloc)
prefix = ".text$";
else if (decl_readonly_section (decl, reloc))
prefix = ".rdata$";
+ else if (DECL_THREAD_LOCAL_P (decl))
+ prefix = ".tls$";
else
prefix = ".data$";
len = strlen (name) + strlen (prefix);
@@ -490,6 +501,9 @@ mingw_pe_asm_named_section (const char *name, unsigned int
flags,
*f++ = 'e';
#endif
+ if (strcmp (name, ".tls$") == 0)
+ *f++ = 'd';
+
if ((flags & (SECTION_CODE | SECTION_WRITE)) == 0)
/* readonly data */
{
diff --git a/gcc/config/mingw/winnt.h b/gcc/config/mingw/winnt.h
index 97fefbcebca..525ac3691f4 100644
--- a/gcc/config/mingw/winnt.h
+++ b/gcc/config/mingw/winnt.h
@@ -30,6 +30,7 @@ extern void mingw_pe_file_end (void);
extern void mingw_pe_maybe_record_exported_symbol (tree, const char *, int);
extern void mingw_pe_record_stub (const char *);
extern unsigned int mingw_pe_section_type_flags (tree, const char *, int);
+extern section *mingw_pe_select_section (tree, int, unsigned HOST_WIDE_INT);
extern void mingw_pe_unique_section (tree, int);
extern bool mingw_pe_valid_dllimport_attribute_p (const_tree);
diff --git a/gcc/configure.ac b/gcc/configure.ac
index bdb22d53e2c..00bfa452691 100644
--- a/gcc/configure.ac
+++ b/gcc/configure.ac
@@ -4166,6 +4166,35 @@ else
[$tls_as_opt], [$conftest_s],,
[set_have_as_tls=yes])
fi
+case $target_os in
+ win32 | pe | cygwin* | mingw32*)
+ if test $set_have_as_tls = yes; then
+ # Hack to check whether ld breaks on @secrel32 for Windows
+ if test $in_tree_ld = yes; then
+ if test "$gcc_cv_gld_major_version" -eq 2 -a
"$gcc_cv_gld_minor_version" -ge 44 -o "$gcc_cv_gld_major_version" -gt 2; then
+ : # ld support for @secrel32 was fixed in this version
+ else
+ AC_MSG_ERROR([ld version is known to have broken secrel32
relocations, configure without --enable-tls or with --disable-tls to remove
this error])
+ fi
+ elif test x$gcc_cv_as != x -a x$gcc_cv_ld != x -a x$gcc_cv_objdump != x;
then
+ echo '.text' > conftest.s
+ echo 'foo: nop' >> conftest.s
+ echo '.data' >> conftest.s
+ echo '.secrel32 foo' >> conftest.s
+ if $gcc_cv_as -o conftest.o conftest.s > /dev/null 2>&1 && $gcc_cv_ld
-o conftest.exe conftest.o > /dev/null; then
+ if $gcc_cv_objdump -h conftest.exe | grep '\.reloc\>' > /dev/null;
then
+ AC_MSG_ERROR([ld has broken secrel32 relocations, configure without
--enable-tls or with --disable-tls to remove this error])
+ fi
+ else
+ AC_MSG_ERROR([Error occurred while checking for broken secrel32
relocations])
+ fi
+ rm -f conftest.s conftest.o conftest.exe
+ else
+ AC_MSG_ERROR([Cannot check for broken secrel32 relocations to determine
support for --enable-tls])
+ fi
+ fi
+ ;;
+esac
if test $set_have_as_tls = yes ; then
AC_DEFINE(HAVE_AS_TLS, 1,
[Define if your assembler and linker support thread-local storage.])
--
2.45.2
