tcg: Add support for integer absolute value

Remove a function of the same name from target/arm/.
Use a branchless implementation of abs gleaned from gcc.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c
index a00d1df37e..0ac291f1c4 100644
--- a/tcg/tcg-op.c
+++ b/tcg/tcg-op.c
@@ -1091,6 +1091,16 @@ void tcg_gen_umax_i32(TCGv_i32 ret, TCGv_i32 a, TCGv_i32 b)
     tcg_gen_movcond_i32(TCG_COND_LTU, ret, a, b, b, a);
 }
 
+void tcg_gen_abs_i32(TCGv_i32 ret, TCGv_i32 a)
+{
+    TCGv_i32 t = tcg_temp_new_i32();
+
+    tcg_gen_sari_i32(t, a, 31);
+    tcg_gen_xor_i32(ret, a, t);
+    tcg_gen_sub_i32(ret, ret, t);
+    tcg_temp_free_i32(t);
+}
+
 /* 64-bit ops */
 
 #if TCG_TARGET_REG_BITS == 32
@@ -2548,6 +2558,16 @@ void tcg_gen_umax_i64(TCGv_i64 ret, TCGv_i64 a, TCGv_i64 b)
     tcg_gen_movcond_i64(TCG_COND_LTU, ret, a, b, b, a);
 }
 
+void tcg_gen_abs_i64(TCGv_i64 ret, TCGv_i64 a)
+{
+    TCGv_i64 t = tcg_temp_new_i64();
+
+    tcg_gen_sari_i64(t, a, 63);
+    tcg_gen_xor_i64(ret, a, t);
+    tcg_gen_sub_i64(ret, ret, t);
+    tcg_temp_free_i64(t);
+}
+
 /* Size changing operations.  */
 
 void tcg_gen_extrl_i64_i32(TCGv_i32 ret, TCGv_i64 arg)