+/*
+ * Widening mul, valid for 32x32 bit -> 64bit only.
+ * Result is low 32bits, high bits returned in res_hi.
+ *
+ * Emits code that is meant to be compiled for the host CPU.
+ */
+LLVMValueRef
+lp_build_mul_32_lohi_cpu(struct lp_build_context *bld,
+ LLVMValueRef a,
+ LLVMValueRef b,
+ LLVMValueRef *res_hi)
+{
+ struct gallivm_state *gallivm = bld->gallivm;
+ LLVMBuilderRef builder = gallivm->builder;
+
+ assert(bld->type.width == 32);
+ assert(bld->type.floating == 0);
+ assert(bld->type.fixed == 0);
+ assert(bld->type.norm == 0);
+
+ /*
+ * XXX: for some reason, with zext/zext/mul/trunc the code llvm produces
+ * for x86 simd is atrocious (even if the high bits weren't required),
+ * trying to handle real 64bit inputs (which of course can't happen due
+ * to using 64bit umul with 32bit numbers zero-extended to 64bit, but
+ * apparently llvm does not recognize this widening mul). This includes 6
+ * (instead of 2) pmuludq plus extra adds and shifts
+ * The same story applies to signed mul, albeit fixing this requires sse41.
+ * https://llvm.org/bugs/show_bug.cgi?id=30845
+ * So, whip up our own code, albeit only for length 4 and 8 (which
+ * should be good enough)...
+ */
+ if ((bld->type.length == 4 || bld->type.length == 8) &&
+ ((util_cpu_caps.has_sse2 && (bld->type.sign == 0)) ||
+ util_cpu_caps.has_sse4_1)) {
+ const char *intrinsic = NULL;
+ LLVMValueRef aeven, aodd, beven, bodd, muleven, mulodd;
+ LLVMValueRef shuf[LP_MAX_VECTOR_WIDTH / 32], shuf_vec;
+ struct lp_type type_wide = lp_wider_type(bld->type);
+ LLVMTypeRef wider_type = lp_build_vec_type(gallivm, type_wide);
+ unsigned i;
+ for (i = 0; i < bld->type.length; i += 2) {
+ shuf[i] = lp_build_const_int32(gallivm, i+1);
+ shuf[i+1] = LLVMGetUndef(LLVMInt32TypeInContext(gallivm->context));
+ }
+ shuf_vec = LLVMConstVector(shuf, bld->type.length);
+ aeven = a;
+ beven = b;
+ aodd = LLVMBuildShuffleVector(builder, aeven, bld->undef, shuf_vec, "");
+ bodd = LLVMBuildShuffleVector(builder, beven, bld->undef, shuf_vec, "");
+
+ if (util_cpu_caps.has_avx2 && bld->type.length == 8) {
+ if (bld->type.sign) {
+ intrinsic = "llvm.x86.avx2.pmul.dq";
+ } else {
+ intrinsic = "llvm.x86.avx2.pmulu.dq";
+ }
+ muleven = lp_build_intrinsic_binary(builder, intrinsic,
+ wider_type, aeven, beven);
+ mulodd = lp_build_intrinsic_binary(builder, intrinsic,
+ wider_type, aodd, bodd);
+ }
+ else {
+ /* for consistent naming look elsewhere... */
+ if (bld->type.sign) {
+ intrinsic = "llvm.x86.sse41.pmuldq";
+ } else {
+ intrinsic = "llvm.x86.sse2.pmulu.dq";
+ }
+ /*
+ * XXX If we only have AVX but not AVX2 this is a pain.
+ * lp_build_intrinsic_binary_anylength() can't handle it
+ * (due to src and dst type not being identical).
+ */
+ if (bld->type.length == 8) {
+ LLVMValueRef aevenlo, aevenhi, bevenlo, bevenhi;
+ LLVMValueRef aoddlo, aoddhi, boddlo, boddhi;
+ LLVMValueRef muleven2[2], mulodd2[2];
+ struct lp_type type_wide_half = type_wide;
+ LLVMTypeRef wtype_half;
+ type_wide_half.length = 2;
+ wtype_half = lp_build_vec_type(gallivm, type_wide_half);
+ aevenlo = lp_build_extract_range(gallivm, aeven, 0, 4);
+ aevenhi = lp_build_extract_range(gallivm, aeven, 4, 4);
+ bevenlo = lp_build_extract_range(gallivm, beven, 0, 4);
+ bevenhi = lp_build_extract_range(gallivm, beven, 4, 4);
+ aoddlo = lp_build_extract_range(gallivm, aodd, 0, 4);
+ aoddhi = lp_build_extract_range(gallivm, aodd, 4, 4);
+ boddlo = lp_build_extract_range(gallivm, bodd, 0, 4);
+ boddhi = lp_build_extract_range(gallivm, bodd, 4, 4);
+ muleven2[0] = lp_build_intrinsic_binary(builder, intrinsic,
+ wtype_half, aevenlo, bevenlo);
+ mulodd2[0] = lp_build_intrinsic_binary(builder, intrinsic,
+ wtype_half, aoddlo, boddlo);
+ muleven2[1] = lp_build_intrinsic_binary(builder, intrinsic,
+ wtype_half, aevenhi, bevenhi);
+ mulodd2[1] = lp_build_intrinsic_binary(builder, intrinsic,
+ wtype_half, aoddhi, boddhi);
+ muleven = lp_build_concat(gallivm, muleven2, type_wide_half, 2);
+ mulodd = lp_build_concat(gallivm, mulodd2, type_wide_half, 2);
+
+ }
+ else {
+ muleven = lp_build_intrinsic_binary(builder, intrinsic,
+ wider_type, aeven, beven);
+ mulodd = lp_build_intrinsic_binary(builder, intrinsic,
+ wider_type, aodd, bodd);
+ }
+ }
+ muleven = LLVMBuildBitCast(builder, muleven, bld->vec_type, "");
+ mulodd = LLVMBuildBitCast(builder, mulodd, bld->vec_type, "");
+
+ for (i = 0; i < bld->type.length; i += 2) {
+ shuf[i] = lp_build_const_int32(gallivm, i + 1);
+ shuf[i+1] = lp_build_const_int32(gallivm, i + 1 + bld->type.length);
+ }
+ shuf_vec = LLVMConstVector(shuf, bld->type.length);
+ *res_hi = LLVMBuildShuffleVector(builder, muleven, mulodd, shuf_vec, "");
+
+ for (i = 0; i < bld->type.length; i += 2) {
+ shuf[i] = lp_build_const_int32(gallivm, i);
+ shuf[i+1] = lp_build_const_int32(gallivm, i + bld->type.length);
+ }
+ shuf_vec = LLVMConstVector(shuf, bld->type.length);
+ return LLVMBuildShuffleVector(builder, muleven, mulodd, shuf_vec, "");
+ }
+ else {
+ return lp_build_mul_32_lohi(bld, a, b, res_hi);
+ }
+}
+
+
+/*
+ * Widening mul, valid for 32x32 bit -> 64bit only.
+ * Result is low 32bits, high bits returned in res_hi.
+ *
+ * Emits generic code.
+ */
+LLVMValueRef
+lp_build_mul_32_lohi(struct lp_build_context *bld,
+ LLVMValueRef a,
+ LLVMValueRef b,
+ LLVMValueRef *res_hi)
+{
+ struct gallivm_state *gallivm = bld->gallivm;
+ LLVMBuilderRef builder = gallivm->builder;
+ LLVMValueRef tmp, shift, res_lo;
+ struct lp_type type_tmp;
+ LLVMTypeRef wide_type, narrow_type;
+
+ type_tmp = bld->type;
+ narrow_type = lp_build_vec_type(gallivm, type_tmp);
+ type_tmp.width *= 2;
+ wide_type = lp_build_vec_type(gallivm, type_tmp);
+ shift = lp_build_const_vec(gallivm, type_tmp, 32);
+
+ if (bld->type.sign) {
+ a = LLVMBuildSExt(builder, a, wide_type, "");
+ b = LLVMBuildSExt(builder, b, wide_type, "");
+ } else {
+ a = LLVMBuildZExt(builder, a, wide_type, "");
+ b = LLVMBuildZExt(builder, b, wide_type, "");
+ }
+ tmp = LLVMBuildMul(builder, a, b, "");
+
+ res_lo = LLVMBuildTrunc(builder, tmp, narrow_type, "");
+
+ /* Since we truncate anyway, LShr and AShr are equivalent. */
+ tmp = LLVMBuildLShr(builder, tmp, shift, "");
+ *res_hi = LLVMBuildTrunc(builder, tmp, narrow_type, "");
+
+ return res_lo;
+}
+
+
+/* a * b + c */
+LLVMValueRef
+lp_build_mad(struct lp_build_context *bld,
+ LLVMValueRef a,
+ LLVMValueRef b,
+ LLVMValueRef c)
+{
+ const struct lp_type type = bld->type;
+ if (type.floating) {
+ return lp_build_fmuladd(bld->gallivm->builder, a, b, c);
+ } else {
+ return lp_build_add(bld, lp_build_mul(bld, a, b), c);
+ }
+}
+