tcg-ia64: Move AREG0 to R32

Since the move away from the global areg0, we're no longer globally
reserving areg0.  Which means our use of R7 clobbers a call-saved
register.  Shift areg0 into the windowed registers.  Indeed, choose
the incoming parameter register that it comes to us by.

This requires moving the register holding the return address elsewhere.
Choose R33 for tidiness.

Acked-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 6 insertions, 7 deletions

diff --git a/tcg/ia64/tcg-target.c b/tcg/ia64/tcg-target.c
index 9fb3832..11a414c 100644
--- a/tcg/ia64/tcg-target.c
+++ b/tcg/ia64/tcg-target.c
@@ -109,7 +109,6 @@ enum {
 };
 
 static const int tcg_target_reg_alloc_order[] = {
-    TCG_REG_R33,
     TCG_REG_R35,
     TCG_REG_R36,
     TCG_REG_R37,
@@ -2404,8 +2403,7 @@ static void tcg_target_qemu_prologue(TCGContext *s)
     tcg_out_bundle(s, miI,
                    tcg_opc_m34(TCG_REG_P0, OPC_ALLOC_M34,
                                TCG_REG_R34, 32, 24, 0),
-                   tcg_opc_a4 (TCG_REG_P0, OPC_ADDS_A4,
-                               TCG_AREG0, 0, TCG_REG_R32),
+                   INSN_NOP_I,
                    tcg_opc_i21(TCG_REG_P0, OPC_MOV_I21,
                                TCG_REG_B6, TCG_REG_R33, 0));
 
@@ -2424,7 +2422,7 @@ static void tcg_target_qemu_prologue(TCGContext *s)
                    tcg_opc_a4 (TCG_REG_P0, OPC_ADDS_A4,
                                TCG_REG_R12, -frame_size, TCG_REG_R12),
                    tcg_opc_i22(TCG_REG_P0, OPC_MOV_I22,
-                               TCG_REG_R32, TCG_REG_B0),
+                               TCG_REG_R33, TCG_REG_B0),
                    tcg_opc_b4 (TCG_REG_P0, OPC_BR_SPTK_MANY_B4, TCG_REG_B6));
 
     /* epilogue */
@@ -2432,7 +2430,7 @@ static void tcg_target_qemu_prologue(TCGContext *s)
     tcg_out_bundle(s, miI,
                    INSN_NOP_M,
                    tcg_opc_i21(TCG_REG_P0, OPC_MOV_I21,
-                               TCG_REG_B0, TCG_REG_R32, 0),
+                               TCG_REG_B0, TCG_REG_R33, 0),
                    tcg_opc_a4 (TCG_REG_P0, OPC_ADDS_A4,
                                TCG_REG_R12, frame_size, TCG_REG_R12));
     tcg_out_bundle(s, miB,
@@ -2489,16 +2487,17 @@ static void tcg_target_init(TCGContext *s)
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R3);   /* internal use */
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R12);  /* stack pointer */
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R13);  /* thread pointer */
-    tcg_regset_set_reg(s->reserved_regs, TCG_REG_R32);  /* return address */
+    tcg_regset_set_reg(s->reserved_regs, TCG_REG_R33);  /* return address */
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R34);  /* PFS */
 
-    /* The following 3 are not in use, are call-saved, but *not* saved
+    /* The following 4 are not in use, are call-saved, but *not* saved
        by the prologue.  Therefore we cannot use them without modifying
        the prologue.  There doesn't seem to be any good reason to use
        these as opposed to the windowed registers.  */
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R4);
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R5);
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R6);
+    tcg_regset_set_reg(s->reserved_regs, TCG_REG_R7);
 
     tcg_add_target_add_op_defs(ia64_op_defs);
 }