[Qemu-devel] [PATCH 5/5] tcg-ppc: Conditionally reserve TCG_GUEST_BASE_REG.

[Richard Henderson <rth@twiddle.net>]

We need not reserve the register unless we're going to use it.

Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 tcg/ppc/tcg-target.c   |    8 ++++----
 tcg/ppc64/tcg-target.c |    9 ++++-----
 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/tcg/ppc/tcg-target.c b/tcg/ppc/tcg-target.c
index ce078e4..654d244 100644
--- a/tcg/ppc/tcg-target.c
+++ b/tcg/ppc/tcg-target.c
@@ -933,7 +933,10 @@ void tcg_target_qemu_prologue (TCGContext *s)
     tcg_out32 (s, STW | RS (0) | RA (1) | (frame_size + LR_OFFSET));
 
 #ifdef CONFIG_USE_GUEST_BASE
-    tcg_out_movi (s, TCG_TYPE_I32, TCG_GUEST_BASE_REG, GUEST_BASE);
+    if (GUEST_BASE) {
+        tcg_out_movi (s, TCG_TYPE_I32, TCG_GUEST_BASE_REG, GUEST_BASE);
+        tcg_regset_set_reg(s->reserved_regs, TCG_GUEST_BASE_REG);
+    }
 #endif
 
     tcg_out32 (s, MTSPR | RS (3) | CTR);
@@ -1914,9 +1917,6 @@ void tcg_target_init(TCGContext *s)
 #ifdef _CALL_SYSV
     tcg_regset_set_reg(s->reserved_regs, TCG_REG_R13);
 #endif
-#ifdef CONFIG_USE_GUEST_BASE
-    tcg_regset_set_reg(s->reserved_regs, TCG_GUEST_BASE_REG);
-#endif
 
     tcg_add_target_add_op_defs(ppc_op_defs);
 }
diff --git a/tcg/ppc64/tcg-target.c b/tcg/ppc64/tcg-target.c
index 2d436a5..a1e643c 100644
--- a/tcg/ppc64/tcg-target.c
+++ b/tcg/ppc64/tcg-target.c
@@ -899,7 +899,10 @@ void tcg_target_qemu_prologue (TCGContext *s)
     tcg_out32 (s, STD | RS (0) | RA (1) | (frame_size + 16));
 
 #ifdef CONFIG_USE_GUEST_BASE
-    tcg_out_movi (s, TCG_TYPE_I64, TCG_GUEST_BASE_REG, GUEST_BASE);
+    if (GUEST_BASE) {
+        tcg_out_movi (s, TCG_TYPE_I64, TCG_GUEST_BASE_REG, GUEST_BASE);
+        tcg_regset_set_reg(s->reserved_regs, TCG_GUEST_BASE_REG);
+    }
 #endif
 
     tcg_out32 (s, MTSPR | RS (3) | CTR);
@@ -1692,9 +1695,5 @@ void tcg_target_init (TCGContext *s)
 #endif
     tcg_regset_set_reg (s->reserved_regs, TCG_REG_R13);
 
-#ifdef CONFIG_USE_GUEST_BASE
-    tcg_regset_set_reg(s->reserved_regs, TCG_GUEST_BASE_REG);
-#endif
-
     tcg_add_target_add_op_defs (ppc_op_defs);
 }
-- 
1.7.0.1