[ARM/FDPIC 10/21] [ARM] FDPIC: Implement legitimize_tls_address_fdpic

[Christophe Lyon]

Support additional relocations: TLS_GD32_FDPIC, TLS_LDM32_FDPIC, and
TLS_IE32_FDPIC.

We do not support the GNU2 TLS dialect.

2018-XX-XX  Christophe Lyon  <christophe.lyon@st.com>
	Mickaël Guêné <mickael.guene@st.com>

	gcc/
	* config/arm/arm.c (tls_reloc): Add TLS_GD32_FDPIC,
	TLS_LDM32_FDPIC and TLS_IE32_FDPIC.
	(arm_call_tls_get_addr_fdpic): New.
	(legitimize_tls_address_fdpic): New.
	(legitimize_tls_address_not_fdpic): New.
	(legitimize_tls_address): Add FDPIC support.
	(arm_emit_tls_decoration): Likewise.

Change-Id: I4ea5034ff654540c4658d0a79fb92f70550cdf4a

diff --git a/gcc/config/arm/arm.c b/gcc/config/arm/arm.c
index 2434602..20b8f66 100644
--- a/gcc/config/arm/arm.c
+++ b/gcc/config/arm/arm.c
@@ -2373,9 +2373,12 @@ char arm_arch_name[] = "__ARM_ARCH_PROFILE__";
 
 enum tls_reloc {
   TLS_GD32,
+  TLS_GD32_FDPIC,
   TLS_LDM32,
+  TLS_LDM32_FDPIC,
   TLS_LDO32,
   TLS_IE32,
+  TLS_IE32_FDPIC,
   TLS_LE32,
   TLS_DESCSEQ	/* GNU scheme */
 };
@@ -8681,6 +8684,30 @@ load_tls_operand (rtx x, rtx reg)
 }
 
 static rtx_insn *
+arm_call_tls_get_addr_fdpic (rtx x, rtx reg, rtx *valuep, int reloc)
+{
+  rtx sum;
+
+  gcc_assert (reloc != TLS_DESCSEQ);
+  start_sequence ();
+
+  sum = gen_rtx_UNSPEC (Pmode,
+			gen_rtvec (2, x, GEN_INT (reloc)),
+			UNSPEC_TLS);
+  reg = load_tls_operand (sum, reg);
+  emit_insn (gen_addsi3 (reg, reg, gen_rtx_REG (Pmode, 9)));
+
+  *valuep = emit_library_call_value (get_tls_get_addr (), NULL_RTX,
+				     LCT_PURE, /* LCT_CONST?  */
+				     Pmode, reg, Pmode);
+
+  rtx_insn *insns = get_insns ();
+  end_sequence ();
+
+  return insns;
+}
+
+static rtx_insn *
 arm_call_tls_get_addr (rtx x, rtx reg, rtx *valuep, int reloc)
 {
   rtx label, labelno, sum;
@@ -8736,8 +8763,84 @@ arm_tls_descseq_addr (rtx x, rtx reg)
   return reg;
 }
 
-rtx
-legitimize_tls_address (rtx x, rtx reg)
+static rtx
+legitimize_tls_address_fdpic (rtx x, rtx reg)
+{
+    rtx dest, ret, eqv, addend, sum, tp;
+    rtx_insn *insns;
+    unsigned int model = SYMBOL_REF_TLS_MODEL (x);
+
+    switch (model)
+      {
+      case TLS_MODEL_GLOBAL_DYNAMIC:
+	if (TARGET_GNU2_TLS)
+	  {
+	    abort ();
+	  }
+	else
+	  {
+	    /* Original scheme.  */
+	    insns = arm_call_tls_get_addr_fdpic (x, reg, &ret, TLS_GD32_FDPIC);
+	    dest = gen_reg_rtx (Pmode);
+	    emit_libcall_block (insns, dest, ret, x);
+	  }
+	return dest;
+	break;
+
+      case TLS_MODEL_LOCAL_DYNAMIC:
+	if (TARGET_GNU2_TLS)
+	  {
+	    abort ();
+	  }
+	else
+	  {
+	    insns = arm_call_tls_get_addr_fdpic (x, reg, &ret, TLS_LDM32_FDPIC);
+	    /* Attach a unique REG_EQUIV, to allow the RTL optimizers to
+	       share the LDM result with other LD model accesses.  */
+	    eqv = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, const1_rtx),
+				  UNSPEC_TLS);
+	    dest = gen_reg_rtx (Pmode);
+	    emit_libcall_block (insns, dest, ret, eqv);
+
+	    /* Load the addend.  */
+	    addend = gen_rtx_UNSPEC (Pmode,
+				     gen_rtvec (2, x, GEN_INT (TLS_LDO32)),
+				     UNSPEC_TLS);
+	    addend = force_reg (SImode, gen_rtx_CONST (SImode, addend));
+	    dest = gen_rtx_PLUS (Pmode, dest, addend);
+	  }
+	return dest;
+	break;
+
+      case TLS_MODEL_INITIAL_EXEC:
+	sum = gen_rtx_UNSPEC (Pmode,
+			      gen_rtvec (2, x, GEN_INT (TLS_IE32_FDPIC)),
+			      UNSPEC_TLS);
+	reg = load_tls_operand (sum, reg);
+	/* FIXME: optimize below? */
+	emit_insn (gen_addsi3 (reg, reg, gen_rtx_REG (Pmode, 9)));
+	emit_insn (gen_movsi (reg, gen_rtx_MEM (Pmode, reg)));
+	tp = arm_load_tp (NULL_RTX);
+
+	return gen_rtx_PLUS (Pmode, tp, reg);
+	break;
+
+      case TLS_MODEL_LOCAL_EXEC:
+	tp = arm_load_tp (NULL_RTX);
+	reg = gen_rtx_UNSPEC (Pmode,
+			      gen_rtvec (2, x, GEN_INT (TLS_LE32)),
+			      UNSPEC_TLS);
+	reg = force_reg (SImode, gen_rtx_CONST (SImode, reg));
+
+	return gen_rtx_PLUS (Pmode, tp, reg);
+
+      default:
+	abort ();
+      }
+}
+
+static rtx
+legitimize_tls_address_not_fdpic (rtx x, rtx reg)
 {
   rtx dest, tp, label, labelno, sum, ret, eqv, addend;
   rtx_insn *insns;
@@ -8831,6 +8934,15 @@ legitimize_tls_address (rtx x, rtx reg)
     }
 }
 
+rtx
+legitimize_tls_address (rtx x, rtx reg)
+{
+    if (TARGET_FDPIC)
+	return legitimize_tls_address_fdpic (x, reg);
+    else
+	return legitimize_tls_address_not_fdpic (x, reg);
+}
+
 /* Try machine-dependent ways of modifying an illegitimate address
    to be legitimate.  If we find one, return the new, valid address.  */
 rtx
@@ -28022,15 +28134,24 @@ arm_emit_tls_decoration (FILE *fp, rtx x)
     case TLS_GD32:
       fputs ("(tlsgd)", fp);
       break;
+    case TLS_GD32_FDPIC:
+      fputs ("(tlsgd_fdpic)", fp);
+      break;
     case TLS_LDM32:
       fputs ("(tlsldm)", fp);
       break;
+    case TLS_LDM32_FDPIC:
+      fputs ("(tlsldm_fdpic)", fp);
+      break;
     case TLS_LDO32:
       fputs ("(tlsldo)", fp);
       break;
     case TLS_IE32:
       fputs ("(gottpoff)", fp);
       break;
+    case TLS_IE32_FDPIC:
+      fputs ("(gottpoff_fdpic)", fp);
+      break;
     case TLS_LE32:
       fputs ("(tpoff)", fp);
       break;
-- 
2.6.3