[PPC64LE] Fix vec_sld semantics for little endian

The vec_sld interface provides access to the vsldoi instruction.
Unlike most of the vec_* interfaces, we do not attempt to change the
generated code for vec_sld based on the endian mode.  It is too
difficult to correctly infer the desired semantics because of
different element types, and the corrected instruction sequence is
expensive, involving loading a permute control vector and performing a
generalized permute.

For GCC, this was implemented as "Don't touch the vec_sld"
implementation.  When it came time for the LLVM implementation, I did
the same thing.  However, this was hasty and incorrect.  In LLVM's
version of altivec.h, vec_sld was previously defined in terms of the
vec_perm interface.  Because vec_perm semantics are adjusted for
little endian, this means that leaving vec_sld untouched causes it to
generate something different for LE than for BE.  Not good.

This patch adjusts the form of vec_perm that is used for vec_sld and
vec_vsldoi, effectively undoing the modifications so that the same
vsldoi instruction will be generated for both BE and LE.

There is an accompanying back-end patch to take care of some small
ripple effects caused by these changes.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@242297 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 203 insertions, 24 deletions

diff --git a/lib/Headers/altivec.h b/lib/Headers/altivec.h
index f52bcbc5b4..5c8eb56405 100644
--- a/lib/Headers/altivec.h
+++ b/lib/Headers/altivec.h
@@ -6563,119 +6563,218 @@ static vector signed char __ATTRS_o_ai vec_sld(vector signed char __a,
                                                vector signed char __b,
                                                unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector unsigned char __ATTRS_o_ai vec_sld(vector unsigned char __a,
                                                  vector unsigned char __b,
                                                  unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector bool char __ATTRS_o_ai vec_sld(vector bool char __a,
                                              vector bool char __b,
                                              unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector signed short __ATTRS_o_ai vec_sld(vector signed short __a,
                                                 vector signed short __b,
                                                 unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector unsigned short __ATTRS_o_ai vec_sld(vector unsigned short __a,
                                                   vector unsigned short __b,
                                                   unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector bool short __ATTRS_o_ai vec_sld(vector bool short __a,
                                               vector bool short __b,
                                               unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector pixel __ATTRS_o_ai vec_sld(vector pixel __a, vector pixel __b,
                                          unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector signed int __ATTRS_o_ai vec_sld(vector signed int __a,
                                               vector signed int __b,
                                               unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector unsigned int __ATTRS_o_ai vec_sld(vector unsigned int __a,
                                                 vector unsigned int __b,
                                                 unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector bool int __ATTRS_o_ai vec_sld(vector bool int __a,
                                             vector bool int __b,
                                             unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector float __ATTRS_o_ai vec_sld(vector float __a, vector float __b,
                                          unsigned const int __c) {
   unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
       (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
                              __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
                              __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 /* vec_vsldoi */
@@ -6683,77 +6782,157 @@ static vector float __ATTRS_o_ai vec_sld(vector float __a, vector float __b,
 static vector signed char __ATTRS_o_ai vec_vsldoi(vector signed char __a,
                                                   vector signed char __b,
                                                   unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector unsigned char __ATTRS_o_ai vec_vsldoi(vector unsigned char __a,
                                                     vector unsigned char __b,
                                                     unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector short __ATTRS_o_ai vec_vsldoi(vector short __a, vector short __b,
                                             unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector unsigned short __ATTRS_o_ai vec_vsldoi(vector unsigned short __a,
                                                      vector unsigned short __b,
                                                      unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector pixel __ATTRS_o_ai vec_vsldoi(vector pixel __a, vector pixel __b,
                                             unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector int __ATTRS_o_ai vec_vsldoi(vector int __a, vector int __b,
                                           unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector unsigned int __ATTRS_o_ai vec_vsldoi(vector unsigned int __a,
                                                    vector unsigned int __b,
                                                    unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 static vector float __ATTRS_o_ai vec_vsldoi(vector float __a, vector float __b,
                                             unsigned char __c) {
+  unsigned char __d = __c & 0x0F;
+#ifdef __LITTLE_ENDIAN__
+  return vec_perm(
+      __b, __a,
+      (vector unsigned char)(16 - __d, 17 - __d, 18 - __d, 19 - __d, 20 - __d,
+                             21 - __d, 22 - __d, 23 - __d, 24 - __d, 25 - __d,
+                             26 - __d, 27 - __d, 28 - __d, 29 - __d, 30 - __d,
+                             31 - __d));
+#else
   return vec_perm(
       __a, __b,
-      (vector unsigned char)(__c, __c + 1, __c + 2, __c + 3, __c + 4, __c + 5,
-                             __c + 6, __c + 7, __c + 8, __c + 9, __c + 10,
-                             __c + 11, __c + 12, __c + 13, __c + 14, __c + 15));
+      (vector unsigned char)(__d, __d + 1, __d + 2, __d + 3, __d + 4, __d + 5,
+                             __d + 6, __d + 7, __d + 8, __d + 9, __d + 10,
+                             __d + 11, __d + 12, __d + 13, __d + 14, __d + 15));
+#endif
 }
 
 /* vec_sll */