[X86][SSE] Replace 128-bit SSE41 PMOVSX intrinsics with native IR

[RKSimon]

Summary

128-bit vector integer sign extensions correctly lower to the pmovsx instructions even for debug builds.

This patch removes the builtins and reimplements the _mm_cvtepi*_epi* intrinsics using builtin_shufflevector (to extract the bottom most subvector) and builtin_convertvector (to actually perform the sign extension).

After this I'll add a patch for the removal/upgrade of the pmovsx intrinsics on the llvm side.

Note: AVX2 256-bit vector integer sign extensions currently don't lower correctly in debug builds if they need the __builtin_shufflevector stage (although I could add the ones that don't need this straightaway).

[qcolombet]

LGTM.

Thanks,
-Quentin

include/clang/Basic/BuiltinsX86.def

 TARGET_BUILTIN(__builtin_ia32_pmaxsb128, "V16cV16cV16c", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmaxsd128, "V4iV4iV4i", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmaxud128, "V4iV4iV4i", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmaxuw128, "V8sV8sV8s", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pminsb128, "V16cV16cV16c", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pminsd128, "V4iV4iV4i", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pminud128, "V4iV4iV4i", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pminuw128, "V8sV8sV8s", "", "sse4.1")
-TARGET_BUILTIN(__builtin_ia32_pmovsxbd128, "V4iV16c", "", "sse4.1")
-TARGET_BUILTIN(__builtin_ia32_pmovsxbq128, "V2LLiV16c", "", "sse4.1")
-TARGET_BUILTIN(__builtin_ia32_pmovsxbw128, "V8sV16c", "", "sse4.1")
-TARGET_BUILTIN(__builtin_ia32_pmovsxdq128, "V2LLiV4i", "", "sse4.1")
-TARGET_BUILTIN(__builtin_ia32_pmovsxwd128, "V4iV8s", "", "sse4.1")
-TARGET_BUILTIN(__builtin_ia32_pmovsxwq128, "V2LLiV8s", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmovzxbd128, "V4iV16c", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmovzxbq128, "V2LLiV16c", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmovzxbw128, "V8sV16c", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmovzxdq128, "V2LLiV4i", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmovzxwd128, "V4iV8s", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmovzxwq128, "V2LLiV8s", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmuldq128, "V2LLiV4iV4i", "", "sse4.1")
 TARGET_BUILTIN(__builtin_ia32_pmulld128, "V4iV4iV4i", "", "sse4.1")

lib/Headers/smmintrin.h

 {
   return (__m128i)((__v2di)__V1 == (__v2di)__V2);
 }
 
 /* SSE4 Packed Integer Sign-Extension.  */
 static __inline__ __m128i __DEFAULT_FN_ATTRS
 _mm_cvtepi8_epi16(__m128i __V)
 {
-  return (__m128i) __builtin_ia32_pmovsxbw128((__v16qi) __V);
+  return (__m128i)__builtin_convertvector(__builtin_shufflevector((__v16qi)__V, (__v16qi)__V, 0, 1, 2, 3, 4, 5, 6, 7), __v8hi);
 }
 
 static __inline__ __m128i __DEFAULT_FN_ATTRS
 _mm_cvtepi8_epi32(__m128i __V)
 {
-  return (__m128i) __builtin_ia32_pmovsxbd128((__v16qi) __V);
+  return (__m128i)__builtin_convertvector(__builtin_shufflevector((__v16qi)__V, (__v16qi)__V, 0, 1, 2, 3), __v4si);
 }
 
 static __inline__ __m128i __DEFAULT_FN_ATTRS
 _mm_cvtepi8_epi64(__m128i __V)
 {
-  return (__m128i) __builtin_ia32_pmovsxbq128((__v16qi) __V);
+  return (__m128i)__builtin_convertvector(__builtin_shufflevector((__v16qi)__V, (__v16qi)__V, 0, 1), __v2di);
 }
 
 static __inline__ __m128i __DEFAULT_FN_ATTRS
 _mm_cvtepi16_epi32(__m128i __V)
 {
-  return (__m128i) __builtin_ia32_pmovsxwd128((__v8hi) __V);
+  return (__m128i)__builtin_convertvector(__builtin_shufflevector((__v8hi)__V, (__v8hi)__V, 0, 1, 2, 3), __v4si);
 }
 
 static __inline__ __m128i __DEFAULT_FN_ATTRS
 _mm_cvtepi16_epi64(__m128i __V)
 {
-  return (__m128i) __builtin_ia32_pmovsxwq128((__v8hi)__V);
+  return (__m128i)__builtin_convertvector(__builtin_shufflevector((__v8hi)__V, (__v8hi)__V, 0, 1), __v2di);
 }
 
 static __inline__ __m128i __DEFAULT_FN_ATTRS
 _mm_cvtepi32_epi64(__m128i __V)
 {
-  return (__m128i) __builtin_ia32_pmovsxdq128((__v4si)__V);
+  return (__m128i)__builtin_convertvector(__builtin_shufflevector((__v4si)__V, (__v4si)__V, 0, 1), __v2di);
 }
 
 /* SSE4 Packed Integer Zero-Extension.  */
 static __inline__ __m128i __DEFAULT_FN_ATTRS
 _mm_cvtepu8_epi16(__m128i __V)
 {
   return (__m128i) __builtin_ia32_pmovzxbw128((__v16qi) __V);
 }

test/CodeGen/builtins-x86.c

#ifdef USE_SSE4
   tmp_V16c = __builtin_ia32_pmaxsb128(tmp_V16c, tmp_V16c);
   tmp_V4i = __builtin_ia32_pmaxsd128(tmp_V4i, tmp_V4i);
   tmp_V4i = __builtin_ia32_pmaxud128(tmp_V4i, tmp_V4i);
   tmp_V8s = __builtin_ia32_pmaxuw128(tmp_V8s, tmp_V8s);
   tmp_V16c = __builtin_ia32_pminsb128(tmp_V16c, tmp_V16c);
   tmp_V4i = __builtin_ia32_pminsd128(tmp_V4i, tmp_V4i);
   tmp_V4i = __builtin_ia32_pminud128(tmp_V4i, tmp_V4i);
   tmp_V8s = __builtin_ia32_pminuw128(tmp_V8s, tmp_V8s);
-  tmp_V4i = __builtin_ia32_pmovsxbd128(tmp_V16c);
-  tmp_V2LLi = __builtin_ia32_pmovsxbq128(tmp_V16c);
-  tmp_V8s = __builtin_ia32_pmovsxbw128(tmp_V16c);
-  tmp_V2LLi = __builtin_ia32_pmovsxdq128(tmp_V4i);
-  tmp_V4i = __builtin_ia32_pmovsxwd128(tmp_V8s);
-  tmp_V2LLi = __builtin_ia32_pmovsxwq128(tmp_V8s);
   tmp_V4i = __builtin_ia32_pmovzxbd128(tmp_V16c);
   tmp_V2LLi = __builtin_ia32_pmovzxbq128(tmp_V16c);
   tmp_V8s = __builtin_ia32_pmovzxbw128(tmp_V16c);
   tmp_V2LLi = __builtin_ia32_pmovzxdq128(tmp_V4i);
   tmp_V4i = __builtin_ia32_pmovzxwd128(tmp_V8s);
   tmp_V2LLi = __builtin_ia32_pmovzxwq128(tmp_V8s);
   tmp_V2LLi = __builtin_ia32_pmuldq128(tmp_V4i, tmp_V4i);
   tmp_V4i = __builtin_ia32_pmulld128(tmp_V4i, tmp_V4i);

test/CodeGen/sse41-builtins.c

__m128i test_mm_cmpeq_epi64(__m128i A, __m128i B) {
   // CHECK-LABEL: test_mm_cmpeq_epi64
   // CHECK: icmp eq <2 x i64>
   // CHECK-ASM: pcmpeqq %xmm{{.*}}, %xmm{{.*}}
   return _mm_cmpeq_epi64(A, B);
 }
 
 __m128i test_mm_cvtepi8_epi16(__m128i a) {
   // CHECK-LABEL: test_mm_cvtepi8_epi16
-  // CHECK: call <8 x i16> @llvm.x86.sse41.pmovsxbw(<16 x i8> {{.*}})
+  // CHECK: sext <8 x i8> {{.*}} to <8 x i16>
   // CHECK-ASM: pmovsxbw %xmm{{.*}}, %xmm{{.*}}
   return _mm_cvtepi8_epi16(a);
 }
 
 __m128i test_mm_cvtepi8_epi32(__m128i a) {
   // CHECK-LABEL: test_mm_cvtepi8_epi32
-  // CHECK: call <4 x i32> @llvm.x86.sse41.pmovsxbd(<16 x i8> {{.*}})
+  // CHECK: sext <4 x i8> {{.*}} to <4 x i32>
   // CHECK-ASM: pmovsxbd %xmm{{.*}}, %xmm{{.*}}
   return _mm_cvtepi8_epi32(a);
 }
 
 __m128i test_mm_cvtepi8_epi64(__m128i a) {
   // CHECK-LABEL: test_mm_cvtepi8_epi64
-  // CHECK: call <2 x i64> @llvm.x86.sse41.pmovsxbq(<16 x i8> {{.*}})
+  // CHECK: sext <2 x i8> {{.*}} to <2 x i64>
   // CHECK-ASM: pmovsxbq %xmm{{.*}}, %xmm{{.*}}
   return _mm_cvtepi8_epi64(a);
 }
 
 __m128i test_mm_cvtepi16_epi32(__m128i a) {
   // CHECK-LABEL: test_mm_cvtepi16_epi32
-  // CHECK: call <4 x i32> @llvm.x86.sse41.pmovsxwd(<8 x i16> {{.*}})
+  // CHECK: sext <4 x i16> {{.*}} to <4 x i32>
   // CHECK-ASM: pmovsxwd %xmm{{.*}}, %xmm{{.*}}
   return _mm_cvtepi16_epi32(a);
 }
 
 __m128i test_mm_cvtepi16_epi64(__m128i a) {
   // CHECK-LABEL: test_mm_cvtepi16_epi64
-  // CHECK: call <2 x i64> @llvm.x86.sse41.pmovsxwq(<8 x i16> {{.*}})
+  // CHECK: sext <2 x i16> {{.*}} to <2 x i64>
   // CHECK-ASM: pmovsxwq %xmm{{.*}}, %xmm{{.*}}
   return _mm_cvtepi16_epi64(a);
 }
 
 __m128i test_mm_cvtepi32_epi64(__m128i a) {
   // CHECK-LABEL: test_mm_cvtepi32_epi64
-  // CHECK: call <2 x i64> @llvm.x86.sse41.pmovsxdq(<4 x i32> {{.*}})
+  // CHECK: sext <2 x i32> {{.*}} to <2 x i64>
   // CHECK-ASM: pmovsxdq %xmm{{.*}}, %xmm{{.*}}
   return _mm_cvtepi32_epi64(a);
 }
 
 __m128i test_mm_cvtepu8_epi16(__m128i a) {
   // CHECK-LABEL: test_mm_cvtepu8_epi16
   // CHECK: call <8 x i16> @llvm.x86.sse41.pmovzxbw(<16 x i8> {{.*}})
   // CHECK-ASM: pmovzxbw %xmm{{.*}}, %xmm{{.*}}