[PowerPC][Altivec] Fix constant argument for vec_dss

[jsji]

Summary

This is similar to vec_ct* in https://reviews.llvm.org/rL304205.

The argument must be a constant, otherwise instruction selection
will fail. always_inline is not enough for isel to always fold
everything away at -O0.

The fix is to turn the function into macros in altivec.h.

Fixes https://bugs.llvm.org/show_bug.cgi?id=43072

[jsji]

Ping..

[• wuzish]

clang/test/CodeGen/builtins-ppc-error.c

78 ↗

(On Diff #217000)

It would be better if add range constraint check at Sema::CheckPPCBuiltinFunctionCall

[jsji]

Add range check and test.

[jsji]

clang/test/CodeGen/builtins-ppc-error.c

78 ↗

(On Diff #217000)

Good point, Done. Thanks.

cfe/trunk/include/clang/Basic/BuiltinsPPC.def

 
 BUILTIN(__builtin_altivec_vrfip, "V4fV4f", "")
 
 BUILTIN(__builtin_altivec_vcfsx, "V4fV4iIi", "")
 BUILTIN(__builtin_altivec_vcfux, "V4fV4iIi", "")
 BUILTIN(__builtin_altivec_vctsxs, "V4SiV4fIi", "")
 BUILTIN(__builtin_altivec_vctuxs, "V4UiV4fIi", "")
 
-BUILTIN(__builtin_altivec_dss, "vUi", "")
+BUILTIN(__builtin_altivec_dss, "vUIi", "")
 BUILTIN(__builtin_altivec_dssall, "v", "")
 BUILTIN(__builtin_altivec_dst, "vvC*iUi", "")
 BUILTIN(__builtin_altivec_dstt, "vvC*iUi", "")
 BUILTIN(__builtin_altivec_dstst, "vvC*iUi", "")
 BUILTIN(__builtin_altivec_dststt, "vvC*iUi", "")
 
 BUILTIN(__builtin_altivec_vexptefp, "V4fV4f", "")
 

cfe/trunk/lib/Headers/altivec.h

 static __inline__ vector double __ATTRS_o_ai vec_div(vector double __a,
                                                      vector double __b) {
   return __a / __b;
 }
 #endif
 
 /* vec_dss */
 
-static __inline__ void __attribute__((__always_inline__)) vec_dss(int __a) {
-  __builtin_altivec_dss(__a);
-}
+#define vec_dss __builtin_altivec_dss
 
 /* vec_dssall */
 
 static __inline__ void __attribute__((__always_inline__)) vec_dssall(void) {
   __builtin_altivec_dssall();
 }
 
 /* vec_dst */

cfe/trunk/lib/Sema/SemaChecking.cpp

bool Sema::CheckPPCBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
   };
 
   switch (BuiltinID) {
   default: return false;
   case PPC::BI__builtin_altivec_crypto_vshasigmaw:
   case PPC::BI__builtin_altivec_crypto_vshasigmad:
     return SemaBuiltinConstantArgRange(TheCall, 1, 0, 1) ||
            SemaBuiltinConstantArgRange(TheCall, 2, 0, 15);
+  case PPC::BI__builtin_altivec_dss:
+    return SemaBuiltinConstantArgRange(TheCall, 0, 0, 3);
   case PPC::BI__builtin_tbegin:
   case PPC::BI__builtin_tend: i = 0; l = 0; u = 1; break;
   case PPC::BI__builtin_tsr: i = 0; l = 0; u = 7; break;
   case PPC::BI__builtin_tabortwc:
   case PPC::BI__builtin_tabortdc: i = 0; l = 0; u = 31; break;
   case PPC::BI__builtin_tabortwci:
   case PPC::BI__builtin_tabortdci:
     return SemaBuiltinConstantArgRange(TheCall, 0, 0, 31) ||

cfe/trunk/test/CodeGen/altivec-dss.c

+// RUN: %clang_cc1 -triple powerpc-linux-gnu -S -O0 -o - %s -target-feature +altivec | FileCheck %s
+
+// REQUIRES: powerpc-registered-target
+
+#include <altivec.h>
+
+// CHECK-LABEL: test1
+// CHECK: dss 
+void test1() {
+  vec_dss(1);
+}

cfe/trunk/test/CodeGen/builtins-ppc-error.c

 void testVCTUXS(int index) {
   vec_vctuxs(vf, index); //expected-error {{argument to '__builtin_altivec_vctuxs' must be a constant integer}}
 }
 
 void testUnpack128(int index) {
   __builtin_unpack_vector_int128(vsllli, index); //expected-error {{argument to '__builtin_unpack_vector_int128' must be a constant integer}}
   __builtin_unpack_vector_int128(vsllli, 5); //expected-error {{argument value 5 is outside the valid range [0, 1]}}
 }
+
+void testDSS(int index) {
+  vec_dss(index); //expected-error {{argument to '__builtin_altivec_dss' must be a constant integer}}
+  vec_dss(5); //expected-error {{argument value 5 is outside the valid range [0, 3]}}
+}