[Qemu-devel] [PATCH v3 07/27] tcg-ppc64: Cleanup tcg_out_movi

[Richard Henderson <rth@twiddle.net>]

The test for using movi32 was sub-optimal for TCG_TYPE_I32, comparing
a signed 32-bit quantity against an unsigned 32-bit quantity.

When possible, use addi+oris for 32-bit unsigned constants.  Otherwise,
standardize on addi+oris+ori instead of addis+ori+rldicl.

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
 tcg/ppc64/tcg-target.c | 36 ++++++++++++++++--------------------
 1 file changed, 16 insertions(+), 20 deletions(-)

diff --git a/tcg/ppc64/tcg-target.c b/tcg/ppc64/tcg-target.c
index 82e1da7..a4951c5 100644
--- a/tcg/ppc64/tcg-target.c
+++ b/tcg/ppc64/tcg-target.c
@@ -477,29 +477,25 @@ static void tcg_out_movi32(TCGContext *s, TCGReg ret, int32_t arg)
     }
 }
 
-static void tcg_out_movi (TCGContext *s, TCGType type,
-                          TCGReg ret, tcg_target_long arg)
+static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg ret,
+                         tcg_target_long arg)
 {
-    int32_t arg32 = arg;
-    arg = type == TCG_TYPE_I32 ? arg & 0xffffffff : arg;
-
-    if (arg == arg32) {
-        tcg_out_movi32 (s, ret, arg32);
-    }
-    else {
-        if ((uint64_t) arg >> 32) {
-            uint16_t h16 = arg >> 16;
-            uint16_t l16 = arg;
-
-            tcg_out_movi32 (s, ret, arg >> 32);
+    if (type == TCG_TYPE_I32 || arg == (int32_t)arg) {
+        tcg_out_movi32(s, ret, arg);
+    } else if (arg == (uint32_t)arg && !(arg & 0x8000)) {
+        tcg_out32(s, ADDI | RT(ret) | RA(0) | (arg & 0xffff));
+        tcg_out32(s, ORIS | RT(ret) | RA(ret) | ((arg >> 16) & 0xffff));
+    } else {
+        int32_t high = arg >> 32;
+        tcg_out_movi32(s, ret, high);
+        if (high) {
             tcg_out_shli64(s, ret, ret, 32);
-            if (h16) tcg_out32 (s, ORIS | RS (ret) | RA (ret) | h16);
-            if (l16) tcg_out32 (s, ORI | RS (ret) | RA (ret) | l16);
         }
-        else {
-            tcg_out_movi32 (s, ret, arg32);
-            if (arg32 < 0)
-                tcg_out_ext32u(s, ret, ret);
+        if (arg & 0xffff0000) {
+            tcg_out32(s, ORIS | RS(ret) | RA(ret) | ((arg >> 16) & 0xffff));
+        }
+        if (arg & 0xffff) {
+            tcg_out32(s, ORI | RS(ret) | RA(ret) | (arg & 0xffff));
         }
     }
 }
-- 
1.8.1.4