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Re: RFA: MIPS TLS support
On Wed, Mar 09, 2005 at 10:36:30PM +0000, Richard Sandiford wrote:
> So mips_symbolic_constant_p seems to be lying when it returns true
> for zero-offset TLS symbols. Why not simply:
>
> - get mips_symbolic_constant_p to return false for TLS constants
> - get mips_const_insns to return 0 for TLS constants
> - handle TLS symbols specially in mips_legitimize_move and
> mips_legitimize_address (as opposed to TLS constants being
> special cases of mips_split_p)?
It took me a while to work out what you wanted me to do, I'm afraid,
but I think I've got it now. How about this? Also includes improved
configure test and untested mips16 support.
I haven't run tests on it yet, but I did verify that glibc built
without any ICEs - usually a good indicator.
--
Daniel Jacobowitz
CodeSourcery, LLC
2005-03-09 Daniel Jacobowitz <dan@codesourcery.com>
Joseph S. Myers <joseph@codesourcery.com>
* configure.ac: Check for MIPS TLS.
* configure: Regenerated.
* config/mips/mips-protos.h (enum mips_symbol_type): Add
SYMBOL_TLS, SYMBOL_TLSGD, SYMBOL_TLSLDM, SYMBOL_DTPREL,
SYMBOL_GOTTPREL, and SYMBOL_TPREL.
* config/mips/mips.c (mips_regno_to_class): Handle V1_REG.
(TARGET_HAVE_TLS, TARGET_CANNOT_FORCE_CONST_MEM): Define.
(mips_classify_symbol, mips_symbolic_constant_p)
(mips_symbolic_address_p, mips_symbol_insns): Handle TLS symbols.
(mips_tls_operand_p, mips_call_tls_get_addr)
(mips_legitimize_tls_address): New functions.
(mips_legitimize_address, mips_legitimize_const_move): Call
mips_legitimize_tls_address.
(override_options): Handle V1_REG and TLS symbols.
* config/mips/mips.h (enum reg_class, REG_CLASS_NAMES)
(REG_CLASS_CONTENTS, GR_REG_CLASS_P): Include V1_REG.
(mips_char_to_class): Document V1_REG.
(HAVE_AS_TLS): Provide default.
* config/mips/mips.md (UNSPEC_TLS_LDM, UNSPEC_TLS_GET_TP): New
constants.
(load_got<mode>): Renamed from *load_got<mode>. Allow when
!TARGET_ABICALLS.
(tls_get_tp_<mode>): New instruction.
Index: gcc/gcc/configure
===================================================================
--- gcc.orig/gcc/configure 2005-03-09 10:03:31.000000000 -0500
+++ gcc/gcc/configure 2005-03-10 15:46:00.555900481 -0500
@@ -13670,6 +13670,23 @@ foo: data8 25
tls_first_minor=13
tls_as_opt=--fatal-warnings
;;
+ mips*-*-*)
+ conftest_s='
+ .section .tdata,"awT",@progbits
+x:
+ .word 2
+ .text
+ addiu $4, $28, %tlsgd(x)
+ addiu $4, $28, %tlsldm(x)
+ lui $4, %dtprel_hi(x)
+ addiu $4, $4, %dtprel_lo(x)
+ lw $4, %gottprel(x)($28)
+ lui $4, %tprel_hi(x)
+ addiu $4, $4, %tprel_lo(x)'
+ tls_first_major=2
+ tls_first_minor=16
+ tls_as_opt='-32 --fatal-warnings'
+ ;;
powerpc-*-*)
conftest_s='
.section ".tdata","awT",@progbits
Index: gcc/gcc/configure.ac
===================================================================
--- gcc.orig/gcc/configure.ac 2005-03-09 10:03:31.000000000 -0500
+++ gcc/gcc/configure.ac 2005-03-10 15:45:56.153943923 -0500
@@ -2353,6 +2353,23 @@ foo: data8 25
tls_first_minor=13
tls_as_opt=--fatal-warnings
;;
+ mips*-*-*)
+ conftest_s='
+ .section .tdata,"awT",@progbits
+x:
+ .word 2
+ .text
+ addiu $4, $28, %tlsgd(x)
+ addiu $4, $28, %tlsldm(x)
+ lui $4, %dtprel_hi(x)
+ addiu $4, $4, %dtprel_lo(x)
+ lw $4, %gottprel(x)($28)
+ lui $4, %tprel_hi(x)
+ addiu $4, $4, %tprel_lo(x)'
+ tls_first_major=2
+ tls_first_minor=16
+ tls_as_opt='-32 --fatal-warnings'
+ ;;
powerpc-*-*)
conftest_s='
.section ".tdata","awT",@progbits
Index: gcc/gcc/config/mips/mips-protos.h
===================================================================
--- gcc.orig/gcc/config/mips/mips-protos.h 2005-02-13 21:49:14.000000000 -0500
+++ gcc/gcc/config/mips/mips-protos.h 2005-03-10 15:28:13.230834461 -0500
@@ -61,6 +61,17 @@ Boston, MA 02111-1307, USA. */
An UNSPEC wrapper around a function's address. It represents the
offset of _gp from the start of the function.
+ SYMBOL_TLS
+ A thread-local symbol.
+
+ SYMBOL_TLSGD
+ SYMBOL_TLSLDM
+ SYMBOL_DTPREL
+ SYMBOL_GOTTPREL
+ SYMBOL_TPREL
+ UNSPEC wrappers around SYMBOL_TLS, corresponding to the
+ thread-local storage relocation operators.
+
SYMBOL_64_HIGH
For a 64-bit symbolic address X, this is the value of
(%highest(X) << 16) + %higher(X).
@@ -82,6 +93,12 @@ enum mips_symbol_type {
SYMBOL_GOTOFF_GLOBAL,
SYMBOL_GOTOFF_CALL,
SYMBOL_GOTOFF_LOADGP,
+ SYMBOL_TLS,
+ SYMBOL_TLSGD,
+ SYMBOL_TLSLDM,
+ SYMBOL_DTPREL,
+ SYMBOL_GOTTPREL,
+ SYMBOL_TPREL,
SYMBOL_64_HIGH,
SYMBOL_64_MID,
SYMBOL_64_LOW
Index: gcc/gcc/config/mips/mips.c
===================================================================
--- gcc.orig/gcc/config/mips/mips.c 2005-03-08 17:18:48.000000000 -0500
+++ gcc/gcc/config/mips/mips.c 2005-03-10 16:24:18.791939387 -0500
@@ -236,6 +236,7 @@ static bool mips_valid_base_register_p (
static bool mips_symbolic_address_p (enum mips_symbol_type, enum machine_mode);
static bool mips_classify_address (struct mips_address_info *, rtx,
enum machine_mode, int);
+static bool mips_tls_operand_p (rtx);
static int mips_symbol_insns (enum mips_symbol_type);
static bool mips16_unextended_reference_p (enum machine_mode mode, rtx, rtx);
static rtx mips_force_temporary (rtx, rtx);
@@ -598,7 +599,7 @@ static const char *mips_hi_relocs[NUM_SY
/* Map hard register number to register class */
const enum reg_class mips_regno_to_class[] =
{
- LEA_REGS, LEA_REGS, M16_NA_REGS, M16_NA_REGS,
+ LEA_REGS, LEA_REGS, M16_NA_REGS, V1_REG,
M16_REGS, M16_REGS, M16_REGS, M16_REGS,
LEA_REGS, LEA_REGS, LEA_REGS, LEA_REGS,
LEA_REGS, LEA_REGS, LEA_REGS, LEA_REGS,
@@ -814,6 +815,12 @@ const struct mips_cpu_info mips_cpu_info
#undef TARGET_EXPAND_BUILTIN
#define TARGET_EXPAND_BUILTIN mips_expand_builtin
+#undef TARGET_HAVE_TLS
+#define TARGET_HAVE_TLS HAVE_AS_TLS
+
+#undef TARGET_CANNOT_FORCE_CONST_MEM
+#define TARGET_CANNOT_FORCE_CONST_MEM mips_tls_operand_p
+
struct gcc_target targetm = TARGET_INITIALIZER;
/* Classify symbol X, which must be a SYMBOL_REF or a LABEL_REF. */
@@ -832,6 +839,9 @@ mips_classify_symbol (rtx x)
gcc_assert (GET_CODE (x) == SYMBOL_REF);
+ if (SYMBOL_REF_TLS_MODEL (x))
+ return SYMBOL_TLS;
+
if (CONSTANT_POOL_ADDRESS_P (x))
{
if (TARGET_MIPS16)
@@ -940,7 +950,11 @@ mips_symbolic_constant_p (rtx x, enum mi
if (UNSPEC_ADDRESS_P (x))
*symbol_type = UNSPEC_ADDRESS_TYPE (x);
else if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF)
- *symbol_type = mips_classify_symbol (x);
+ {
+ *symbol_type = mips_classify_symbol (x);
+ if (*symbol_type == SYMBOL_TLS)
+ return false;
+ }
else
return false;
@@ -990,6 +1004,12 @@ mips_symbolic_constant_p (rtx x, enum mi
case SYMBOL_GOTOFF_GLOBAL:
case SYMBOL_GOTOFF_CALL:
case SYMBOL_GOTOFF_LOADGP:
+ case SYMBOL_TLSGD:
+ case SYMBOL_TLSLDM:
+ case SYMBOL_DTPREL:
+ case SYMBOL_TPREL:
+ case SYMBOL_GOTTPREL:
+ case SYMBOL_TLS:
return false;
}
gcc_unreachable ();
@@ -1087,6 +1107,14 @@ mips_symbolic_address_p (enum mips_symbo
/* The address will have to be loaded from the GOT first. */
return false;
+ case SYMBOL_TLSGD:
+ case SYMBOL_TLSLDM:
+ case SYMBOL_DTPREL:
+ case SYMBOL_TPREL:
+ case SYMBOL_GOTTPREL:
+ case SYMBOL_TLS:
+ return false;
+
case SYMBOL_GOTOFF_PAGE:
case SYMBOL_GOTOFF_GLOBAL:
case SYMBOL_GOTOFF_CALL:
@@ -1151,6 +1179,17 @@ mips_classify_address (struct mips_addre
return false;
}
}
+
+/* Return true if X is a thread-local symbol. */
+
+static bool
+mips_tls_operand_p (rtx x)
+{
+ if (GET_CODE (x) != SYMBOL_REF)
+ return false;
+
+ return !!SYMBOL_REF_TLS_MODEL (x);
+}
/* Return the number of instructions needed to load a symbol of the
given type into a register. If valid in an address, the same number
@@ -1220,8 +1259,19 @@ mips_symbol_insns (enum mips_symbol_type
case SYMBOL_64_HIGH:
case SYMBOL_64_MID:
case SYMBOL_64_LOW:
+ case SYMBOL_TPREL:
+ case SYMBOL_DTPREL:
/* Check whether the offset is a 16- or 32-bit value. */
return mips_split_p[type] ? 2 : 1;
+
+ case SYMBOL_TLS:
+ /* We don't treat a bare TLS symbol as a constant. */
+ return 0;
+
+ case SYMBOL_GOTTPREL:
+ case SYMBOL_TLSGD:
+ case SYMBOL_TLSLDM:
+ return 1;
}
gcc_unreachable ();
}
@@ -1518,6 +1568,122 @@ mips_add_offset (rtx temp, rtx reg, HOST
return plus_constant (reg, offset);
}
+/* Emit a call to __tls_get_addr. */
+
+static GTY(()) rtx mips_tls_symbol;
+
+static rtx
+mips_call_tls_get_addr (rtx sym, enum mips_symbol_type type, rtx v0)
+{
+ rtx insn, loc, tga, a0;
+
+ a0 = gen_rtx_REG (Pmode, GP_ARG_FIRST);
+
+ if (!mips_tls_symbol)
+ mips_tls_symbol = init_one_libfunc ("__tls_get_addr");
+
+ loc = mips_unspec_address (sym, type);
+
+ start_sequence ();
+
+ if (Pmode == DImode)
+ gen_adddi3 (a0, pic_offset_table_rtx, loc);
+ else
+ gen_addsi3 (a0, pic_offset_table_rtx, loc);
+ tga = gen_rtx_MEM (Pmode, mips_tls_symbol);
+ insn = gen_call_value (v0, tga, const0_rtx, const0_rtx);
+ insn = emit_call_insn (insn);
+ CONST_OR_PURE_CALL_P (insn) = 1;
+ use_reg (&CALL_INSN_FUNCTION_USAGE (insn), v0);
+ use_reg (&CALL_INSN_FUNCTION_USAGE (insn), a0);
+ insn = get_insns ();
+
+ end_sequence ();
+
+ return insn;
+}
+
+/* Generate the code to access a TLS SYMBOL_REF. */
+
+static rtx
+mips_legitimize_tls_address (rtx loc)
+{
+ rtx dest, insn, v0, v1, tmp1, tmp2, eqv;
+ enum tls_model model;
+
+ dest = gen_reg_rtx (Pmode);
+ v0 = gen_rtx_REG (Pmode, GP_RETURN);
+ v1 = gen_rtx_REG (Pmode, GP_RETURN + 1);
+
+ model = SYMBOL_REF_TLS_MODEL (loc);
+
+ /* MIPS16 does not have an instruction to read the thread pointer,
+ so fall back to the dynamic models. */
+
+ if (TARGET_MIPS16 && model == TLS_MODEL_INITIAL_EXEC)
+ model = TLS_MODEL_GLOBAL_DYNAMIC;
+ else if (TARGET_MIPS16 && model == TLS_MODEL_LOCAL_EXEC)
+ model = TLS_MODEL_LOCAL_DYNAMIC;
+
+ switch (model)
+ {
+ case TLS_MODEL_GLOBAL_DYNAMIC:
+ insn = mips_call_tls_get_addr (loc, SYMBOL_TLSGD, v0);
+ emit_libcall_block (insn, dest, v0, loc);
+ break;
+
+ case TLS_MODEL_LOCAL_DYNAMIC:
+ insn = mips_call_tls_get_addr (loc, SYMBOL_TLSLDM, v0);
+
+ tmp1 = gen_reg_rtx (Pmode);
+ eqv = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, const0_rtx),
+ UNSPEC_TLS_LDM);
+ emit_libcall_block (insn, tmp1, v0, eqv);
+
+ tmp2 = gen_reg_rtx (Pmode);
+ tmp2 = mips_unspec_offset_high (tmp2, pic_offset_table_rtx,
+ loc, SYMBOL_DTPREL);
+ dest = gen_rtx_LO_SUM (Pmode, tmp2,
+ mips_unspec_address (loc, SYMBOL_DTPREL));
+ break;
+
+ case TLS_MODEL_INITIAL_EXEC:
+ tmp1 = gen_reg_rtx (Pmode);
+ tmp2 = mips_unspec_address (loc, SYMBOL_GOTTPREL);
+ if (Pmode == DImode)
+ {
+ emit_insn (gen_tls_get_tp_di (v1));
+ emit_insn (gen_load_gotdi (tmp1, pic_offset_table_rtx, tmp2));
+ emit_insn (gen_adddi3 (dest, tmp1, v1));
+ }
+ else
+ {
+ emit_insn (gen_tls_get_tp_si (v1));
+ emit_insn (gen_load_gotsi (tmp1, pic_offset_table_rtx, tmp2));
+ emit_insn (gen_addsi3 (dest, tmp1, v1));
+ }
+ break;
+
+ case TLS_MODEL_LOCAL_EXEC:
+ tmp1 = gen_reg_rtx (Pmode);
+
+ if (Pmode == DImode)
+ emit_insn (gen_tls_get_tp_di (v1));
+ else
+ emit_insn (gen_tls_get_tp_si (v1));
+
+ tmp1 = gen_reg_rtx (Pmode);
+ tmp1 = mips_unspec_offset_high (tmp1, v1, loc, SYMBOL_TPREL);
+ dest = gen_rtx_LO_SUM (Pmode, tmp1,
+ mips_unspec_address (loc, SYMBOL_TPREL));
+ break;
+
+ default:
+ abort ();
+ }
+
+ return dest;
+}
/* This function is used to implement LEGITIMIZE_ADDRESS. If *XLOC can
be legitimized in a way that the generic machinery might not expect,
@@ -1529,6 +1695,12 @@ mips_legitimize_address (rtx *xloc, enum
{
enum mips_symbol_type symbol_type;
+ if (mips_tls_operand_p (*xloc))
+ {
+ *xloc = mips_legitimize_tls_address (*xloc);
+ return true;
+ }
+
/* See if the address can split into a high part and a LO_SUM. */
if (mips_symbolic_constant_p (*xloc, &symbol_type)
&& mips_symbolic_address_p (symbol_type, mode)
@@ -1704,6 +1876,12 @@ mips_legitimize_const_move (enum machine
return;
}
+ if (mips_tls_operand_p (src))
+ {
+ emit_move_insn (dest, mips_legitimize_tls_address (src));
+ return;
+ }
+
/* See if the symbol can be split. For mips16, this is often worse than
forcing it in the constant pool since it needs the single-register form
of addiu or daddiu. */
@@ -4317,6 +4495,7 @@ override_options (void)
GR_REGS);
mips_char_to_class['e'] = LEA_REGS;
mips_char_to_class['j'] = PIC_FN_ADDR_REG;
+ mips_char_to_class['v'] = V1_REG;
mips_char_to_class['y'] = GR_REGS;
mips_char_to_class['z'] = ST_REGS;
mips_char_to_class['B'] = COP0_REGS;
@@ -4505,6 +4684,17 @@ override_options (void)
mips_lo_relocs[SYMBOL_GOTOFF_LOADGP] = "%lo(%neg(%gp_rel(";
}
+ /* Thread-local relocation operators. */
+ mips_lo_relocs[SYMBOL_TLSGD] = "%tlsgd(";
+ mips_lo_relocs[SYMBOL_TLSLDM] = "%tlsldm(";
+ mips_split_p[SYMBOL_DTPREL] = 1;
+ mips_hi_relocs[SYMBOL_DTPREL] = "%dtprel_hi(";
+ mips_lo_relocs[SYMBOL_DTPREL] = "%dtprel_lo(";
+ mips_lo_relocs[SYMBOL_GOTTPREL] = "%gottprel(";
+ mips_split_p[SYMBOL_TPREL] = 1;
+ mips_hi_relocs[SYMBOL_TPREL] = "%tprel_hi(";
+ mips_lo_relocs[SYMBOL_TPREL] = "%tprel_lo(";
+
/* Default to working around R4000 errata only if the processor
was selected explicitly. */
if ((target_flags_explicit & MASK_FIX_R4000) == 0
Index: gcc/gcc/config/mips/mips.h
===================================================================
--- gcc.orig/gcc/config/mips/mips.h 2005-03-08 17:18:48.000000000 -0500
+++ gcc/gcc/config/mips/mips.h 2005-03-10 15:26:18.794218346 -0500
@@ -1705,6 +1705,7 @@ enum reg_class
T_REG, /* mips16 T register ($24) */
M16_T_REGS, /* mips16 registers plus T register */
PIC_FN_ADDR_REG, /* SVR4 PIC function address register */
+ V1_REG, /* Register $v1 ($3) used for TLS access. */
LEA_REGS, /* Every GPR except $25 */
GR_REGS, /* integer registers */
FP_REGS, /* floating point registers */
@@ -1743,6 +1744,7 @@ enum reg_class
"T_REG", \
"M16_T_REGS", \
"PIC_FN_ADDR_REG", \
+ "V1_REG", \
"LEA_REGS", \
"GR_REGS", \
"FP_REGS", \
@@ -1784,7 +1786,8 @@ enum reg_class
{ 0x01000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* mips16 T register */ \
{ 0x010300fc, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* mips16 and T regs */ \
{ 0x02000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* SVR4 PIC function address register */ \
- { 0xfdffffff, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* Every other GPR */ \
+ { 0x00000008, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* only $v1 */ \
+ { 0xfdffffff, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* Every other GPR except $25 */ \
{ 0xffffffff, 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* integer registers */ \
{ 0x00000000, 0xffffffff, 0x00000000, 0x00000000, 0x00000000, 0x00000000 }, /* floating registers*/ \
{ 0x00000000, 0x00000000, 0x00000001, 0x00000000, 0x00000000, 0x00000000 }, /* hi register */ \
@@ -1840,6 +1843,7 @@ extern const enum reg_class mips_regno_t
#define GR_REG_CLASS_P(CLASS) \
((CLASS) == GR_REGS || (CLASS) == M16_REGS || (CLASS) == T_REG \
|| (CLASS) == M16_T_REGS || (CLASS) == M16_NA_REGS \
+ || (CLASS) == V1_REG \
|| (CLASS) == PIC_FN_ADDR_REG || (CLASS) == LEA_REGS)
/* This macro is also used later on in the file. */
@@ -1887,6 +1891,7 @@ extern const enum reg_class mips_regno_t
'f' Floating point registers
'h' Hi register
'l' Lo register
+ 'v' $v1 only
'x' Multiply/divide registers
'z' FP Status register
'B' Cop0 register
@@ -3022,3 +3027,7 @@ while (0)
" TEXT_SECTION_ASM_OP);
#endif
#endif
+
+#ifndef HAVE_AS_TLS
+#define HAVE_AS_TLS 0
+#endif
Index: gcc/gcc/config/mips/mips.md
===================================================================
--- gcc.orig/gcc/config/mips/mips.md 2005-03-08 17:18:48.000000000 -0500
+++ gcc/gcc/config/mips/mips.md 2005-03-10 16:24:05.026224432 -0500
@@ -45,6 +45,8 @@
(UNSPEC_LOAD_GOT 24)
(UNSPEC_GP 25)
(UNSPEC_MFHILO 26)
+ (UNSPEC_TLS_LDM 27)
+ (UNSPEC_TLS_GET_TP 28)
(UNSPEC_ADDRESS_FIRST 100)
@@ -3017,12 +3019,12 @@ beq\t%2,%.,1b\;\
;; We could use MEMs, but an unspec gives more optimization
;; opportunities.
-(define_insn "*load_got<mode>"
+(define_insn "load_got<mode>"
[(set (match_operand:P 0 "register_operand" "=d")
(unspec:P [(match_operand:P 1 "register_operand" "d")
(match_operand:P 2 "immediate_operand" "")]
UNSPEC_LOAD_GOT))]
- "TARGET_ABICALLS"
+ ""
"<load>\t%0,%R2(%1)"
[(set_attr "type" "load")
(set_attr "mode" "<MODE>")
@@ -5270,6 +5272,17 @@ beq\t%2,%.,1b\;\
[(match_dup 0)]
{ operands[0] = mips_rewrite_small_data (operands[0]); })
+; Thread-Local Storage
+
+(define_insn "tls_get_tp_<mode>"
+ [(set (match_operand:P 0 "register_operand" "=v")
+ (unspec:P [(const_int 0)]
+ UNSPEC_TLS_GET_TP))]
+ "HAVE_AS_TLS && !TARGET_MIPS16"
+ ".set\tpush\;.set\tmips32r2\t\;rdhwr\t%0,$29\;.set\tpop"
+ [(set_attr "type" "unknown")
+ (set_attr "mode" "<MODE>")])
+
; The MIPS Paired-Single Floating Point and MIPS-3D Instructions.
(include "mips-ps-3d.md")