[PATCH 01/29] tcg: Introduce TCG_COND_TST{EQ,NE}

[Richard Henderson <richard.henderson@linaro.org>]

Add the enumerators, adjust the helpers to match, and dump.
Not supported anywhere else just yet.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 include/tcg/tcg-cond.h | 49 ++++++++++++++++++++++++++++++++----------
 tcg/tcg.c              |  4 +++-
 docs/devel/tcg-ops.rst |  2 ++
 3 files changed, 43 insertions(+), 12 deletions(-)

diff --git a/include/tcg/tcg-cond.h b/include/tcg/tcg-cond.h
index 2a38a386d4..bf3fcf5968 100644
--- a/include/tcg/tcg-cond.h
+++ b/include/tcg/tcg-cond.h
@@ -49,6 +49,9 @@ typedef enum {
     TCG_COND_GEU    = 0 | 4 | 0 | 1,
     TCG_COND_LEU    = 8 | 4 | 0 | 0,
     TCG_COND_GTU    = 8 | 4 | 0 | 1,
+    /* "test" i.e. and then compare vs 0 */
+    TCG_COND_TSTEQ  = 8 | 4 | 2 | 0,
+    TCG_COND_TSTNE  = 8 | 4 | 2 | 1,
 } TCGCond;
 
 /* Invert the sense of the comparison.  */
@@ -60,25 +63,49 @@ static inline TCGCond tcg_invert_cond(TCGCond c)
 /* Swap the operands in a comparison.  */
 static inline TCGCond tcg_swap_cond(TCGCond c)
 {
-    return c & 6 ? (TCGCond)(c ^ 9) : c;
+    return (c + 2) & 4 ? (TCGCond)(c ^ 9) : c;
 }
 
-/* Create an "unsigned" version of a "signed" comparison.  */
-static inline TCGCond tcg_unsigned_cond(TCGCond c)
+/* Must a comparison be considered signed?  */
+static inline bool is_signed_cond(TCGCond c)
 {
-    return c & 2 ? (TCGCond)(c ^ 6) : c;
-}
-
-/* Create a "signed" version of an "unsigned" comparison.  */
-static inline TCGCond tcg_signed_cond(TCGCond c)
-{
-    return c & 4 ? (TCGCond)(c ^ 6) : c;
+    return (c & 6) == 2;
 }
 
 /* Must a comparison be considered unsigned?  */
 static inline bool is_unsigned_cond(TCGCond c)
 {
-    return (c & 4) != 0;
+    return (c & 6) == 4;
+}
+
+/* Must a comparison be considered a test?  */
+static inline bool is_tst_cond(TCGCond c)
+{
+    return (c | 1) == 0xf;
+}
+
+/* Create an "unsigned" version of a "signed" comparison.  */
+static inline TCGCond tcg_unsigned_cond(TCGCond c)
+{
+    return is_signed_cond(c) ? (TCGCond)(c ^ 6) : c;
+}
+
+/* Create a "signed" version of an "unsigned" comparison.  */
+static inline TCGCond tcg_signed_cond(TCGCond c)
+{
+    return is_unsigned_cond(c) ? (TCGCond)(c ^ 6) : c;
+}
+
+/* Create the eq/ne version of a tsteq/tstne comparison.  */
+static inline TCGCond tcg_tst_eqne_cond(TCGCond c)
+{
+    return is_tst_cond(c) ? (TCGCond)(c ^ 6) : c;
+}
+
+/* Create the lt/ge version of a tstne/tsteq comparison of the sign.  */
+static inline TCGCond tcg_tst_ltge_cond(TCGCond c)
+{
+    return is_tst_cond(c) ? (TCGCond)(c ^ (8 | 4 | 1)) : c;
 }
 
 /*
diff --git a/tcg/tcg.c b/tcg/tcg.c
index 35158a0846..57d0583fe7 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -2378,7 +2378,9 @@ static const char * const cond_name[] =
     [TCG_COND_LTU] = "ltu",
     [TCG_COND_GEU] = "geu",
     [TCG_COND_LEU] = "leu",
-    [TCG_COND_GTU] = "gtu"
+    [TCG_COND_GTU] = "gtu",
+    [TCG_COND_TSTEQ] = "tsteq",
+    [TCG_COND_TSTNE] = "tstne",
 };
 
 static const char * const ldst_name[(MO_BSWAP | MO_SSIZE) + 1] =
diff --git a/docs/devel/tcg-ops.rst b/docs/devel/tcg-ops.rst
index 8ae59ea02b..d46b625e0e 100644
--- a/docs/devel/tcg-ops.rst
+++ b/docs/devel/tcg-ops.rst
@@ -253,6 +253,8 @@ Jumps/Labels
        |   ``TCG_COND_GEU /* unsigned */``
        |   ``TCG_COND_LEU /* unsigned */``
        |   ``TCG_COND_GTU /* unsigned */``
+       |   ``TCG_COND_TSTEQ /* t1 & t2 == 0 */``
+       |   ``TCG_COND_TSTNE /* t1 & t2 != 0 */``
 
 Arithmetic
 ----------
-- 
2.34.1