intel/common: Add a MI command builder

Reviewed-by: Lionel Landwerlin <[email protected]>

1 files changed, 691 insertions, 0 deletions

diff --git a/src/intel/common/gen_mi_builder.h b/src/intel/common/gen_mi_builder.h
new file mode 100644
index 00000000000..3dd8fcb739c
--- /dev/null
+++ b/src/intel/common/gen_mi_builder.h
@@ -0,0 +1,691 @@
+/*
+ * Copyright © 2019 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef GEN_MI_BUILDER_H
+#define GEN_MI_BUILDER_H
+
+#include "util/bitscan.h"
+#include "util/fast_idiv_by_const.h"
+#include "util/u_math.h"
+
+#ifndef GEN_MI_BUILDER_NUM_ALLOC_GPRS
+/** The number of GPRs the MI builder is allowed to allocate
+ *
+ * This may be set by a user of this API so that it can reserve some GPRs at
+ * the top end for its own use.
+ */
+#define GEN_MI_BUILDER_NUM_ALLOC_GPRS 16
+#endif
+
+/** These must be defined by the user of the builder
+ *
+ * void *__gen_get_batch_dwords(__gen_user_data *user_data,
+ *                              unsigned num_dwords);
+ *
+ * __gen_address_type
+ * __gen_address_offset(__gen_address_type addr, uint64_t offset);
+ *
+ */
+
+/*
+ * Start of the actual MI builder
+ */
+
+#define __genxml_cmd_length(cmd) cmd ## _length
+#define __genxml_cmd_header(cmd) cmd ## _header
+#define __genxml_cmd_pack(cmd) cmd ## _pack
+
+#define gen_mi_builder_pack(b, cmd, dst, name)                          \
+   for (struct cmd name = { __genxml_cmd_header(cmd) },                 \
+        *_dst = (struct cmd *)(dst); __builtin_expect(_dst != NULL, 1); \
+        __genxml_cmd_pack(cmd)((b)->user_data, (void *)_dst, &name),    \
+        _dst = NULL)
+
+#define gen_mi_builder_emit(b, cmd, name)                               \
+   gen_mi_builder_pack((b), cmd, __gen_get_batch_dwords((b)->user_data, __genxml_cmd_length(cmd)), name)
+
+
+enum gen_mi_value_type {
+   GEN_MI_VALUE_TYPE_IMM,
+   GEN_MI_VALUE_TYPE_MEM32,
+   GEN_MI_VALUE_TYPE_MEM64,
+   GEN_MI_VALUE_TYPE_REG32,
+   GEN_MI_VALUE_TYPE_REG64,
+};
+
+struct gen_mi_value {
+   enum gen_mi_value_type type;
+
+   union {
+      uint64_t imm;
+      __gen_address_type addr;
+      uint32_t reg;
+   };
+
+#if GEN_GEN >= 7 || GEN_IS_HASWELL
+   bool invert;
+#endif
+};
+
+#if GEN_GEN >= 9
+#define GEN_MI_BUILDER_MAX_MATH_DWORDS 256
+#else
+#define GEN_MI_BUILDER_MAX_MATH_DWORDS 64
+#endif
+
+struct gen_mi_builder {
+   __gen_user_data *user_data;
+
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+   uint32_t gprs;
+   uint8_t gpr_refs[GEN_MI_BUILDER_NUM_ALLOC_GPRS];
+
+   unsigned num_math_dwords;
+   uint32_t math_dwords[GEN_MI_BUILDER_MAX_MATH_DWORDS];
+#endif
+};
+
+static inline void
+gen_mi_builder_init(struct gen_mi_builder *b, __gen_user_data *user_data)
+{
+   memset(b, 0, sizeof(*b));
+   b->user_data = user_data;
+
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+   b->gprs = 0;
+   b->num_math_dwords = 0;
+#endif
+}
+
+static inline void
+gen_mi_builder_flush_math(struct gen_mi_builder *b)
+{
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+   if (b->num_math_dwords == 0)
+      return;
+
+   uint32_t *dw = (uint32_t *)__gen_get_batch_dwords(b->user_data,
+                                                     1 + b->num_math_dwords);
+   gen_mi_builder_pack(b, GENX(MI_MATH), dw, math) {
+      math.DWordLength = 1 + b->num_math_dwords - GENX(MI_MATH_length_bias);
+   }
+   memcpy(dw + 1, b->math_dwords, b->num_math_dwords * sizeof(uint32_t));
+   b->num_math_dwords = 0;
+#endif
+}
+
+#define _GEN_MI_BUILDER_GPR_BASE 0x2600
+/* The actual hardware limit on GPRs */
+#define _GEN_MI_BUILDER_NUM_HW_GPRS 16
+
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+
+static inline bool
+gen_mi_value_is_gpr(struct gen_mi_value val)
+{
+   return (val.type == GEN_MI_VALUE_TYPE_REG32 ||
+           val.type == GEN_MI_VALUE_TYPE_REG64) &&
+          val.reg >= _GEN_MI_BUILDER_GPR_BASE &&
+          val.reg < _GEN_MI_BUILDER_GPR_BASE +
+                    _GEN_MI_BUILDER_NUM_HW_GPRS * 8;
+}
+
+static inline bool
+_gen_mi_value_is_allocated_gpr(struct gen_mi_value val)
+{
+   return (val.type == GEN_MI_VALUE_TYPE_REG32 ||
+           val.type == GEN_MI_VALUE_TYPE_REG64) &&
+          val.reg >= _GEN_MI_BUILDER_GPR_BASE &&
+          val.reg < _GEN_MI_BUILDER_GPR_BASE +
+                    GEN_MI_BUILDER_NUM_ALLOC_GPRS * 8;
+}
+
+static inline uint32_t
+_gen_mi_value_as_gpr(struct gen_mi_value val)
+{
+   assert(gen_mi_value_is_gpr(val));
+   assert(val.reg % 8 == 0);
+   return (val.reg - _GEN_MI_BUILDER_GPR_BASE) / 8;
+}
+
+static inline struct gen_mi_value
+gen_mi_new_gpr(struct gen_mi_builder *b)
+{
+   unsigned gpr = ffs(~b->gprs) - 1;
+   assert(gpr < GEN_MI_BUILDER_NUM_ALLOC_GPRS);
+   assert(b->gpr_refs[gpr] == 0);
+   b->gprs |= (1u << gpr);
+   b->gpr_refs[gpr] = 1;
+
+   return (struct gen_mi_value) {
+      .type = GEN_MI_VALUE_TYPE_REG64,
+      .reg = _GEN_MI_BUILDER_GPR_BASE + gpr * 8,
+   };
+}
+#endif /* GEN_GEN >= 8 || GEN_IS_HASWELL */
+
+/** Take a reference to a gen_mi_value
+ *
+ * The MI builder uses reference counting to automatically free ALU GPRs for
+ * re-use in calculations.  All gen_mi_* math functions consume the reference
+ * they are handed for each source and return a reference to a value which the
+ * caller must consume.  In particular, if you pas the same value into a
+ * single gen_mi_* math function twice (say to add a number to itself), you
+ * are responsible for calling gen_mi_value_ref() to get a second reference
+ * because the gen_mi_* math function will consume it twice.
+ */
+static inline struct gen_mi_value
+gen_mi_value_ref(struct gen_mi_builder *b, struct gen_mi_value val)
+{
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+   if (_gen_mi_value_is_allocated_gpr(val)) {
+      unsigned gpr = _gen_mi_value_as_gpr(val);
+      assert(gpr < GEN_MI_BUILDER_NUM_ALLOC_GPRS);
+      assert(b->gprs & (1u << gpr));
+      assert(b->gpr_refs[gpr] < UINT8_MAX);
+      b->gpr_refs[gpr]++;
+   }
+#endif /* GEN_GEN >= 8 || GEN_IS_HASWELL */
+
+   return val;
+}
+
+/** Drop a reference to a gen_mi_value
+ *
+ * See also gen_mi_value_ref.
+ */
+static inline void
+gen_mi_value_unref(struct gen_mi_builder *b, struct gen_mi_value val)
+{
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+   if (_gen_mi_value_is_allocated_gpr(val)) {
+      unsigned gpr = _gen_mi_value_as_gpr(val);
+      assert(gpr < GEN_MI_BUILDER_NUM_ALLOC_GPRS);
+      assert(b->gprs & (1u << gpr));
+      assert(b->gpr_refs[gpr] > 0);
+      if (--b->gpr_refs[gpr] == 0)
+         b->gprs &= ~(1u << gpr);
+   }
+#endif /* GEN_GEN >= 8 || GEN_IS_HASWELL */
+}
+
+static inline struct gen_mi_value
+gen_mi_imm(uint64_t imm)
+{
+   return (struct gen_mi_value) {
+      .type = GEN_MI_VALUE_TYPE_IMM,
+      .imm = imm,
+   };
+}
+
+static inline struct gen_mi_value
+gen_mi_reg32(uint32_t reg)
+{
+   struct gen_mi_value val = {
+      .type = GEN_MI_VALUE_TYPE_REG32,
+      .reg = reg,
+   };
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+   assert(!_gen_mi_value_is_allocated_gpr(val));
+#endif
+   return val;
+}
+
+static inline struct gen_mi_value
+gen_mi_reg64(uint32_t reg)
+{
+   struct gen_mi_value val = {
+      .type = GEN_MI_VALUE_TYPE_REG64,
+      .reg = reg,
+   };
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+   assert(!_gen_mi_value_is_allocated_gpr(val));
+#endif
+   return val;
+}
+
+static inline struct gen_mi_value
+gen_mi_mem32(__gen_address_type addr)
+{
+   return (struct gen_mi_value) {
+      .type = GEN_MI_VALUE_TYPE_MEM32,
+      .addr = addr,
+   };
+}
+
+static inline struct gen_mi_value
+gen_mi_mem64(__gen_address_type addr)
+{
+   return (struct gen_mi_value) {
+      .type = GEN_MI_VALUE_TYPE_MEM64,
+      .addr = addr,
+   };
+}
+
+static inline struct gen_mi_value
+gen_mi_value_half(struct gen_mi_value value, bool top_32_bits)
+{
+   switch (value.type) {
+   case GEN_MI_VALUE_TYPE_IMM:
+      if (top_32_bits)
+         value.imm >>= 32;
+      else
+         value.imm &= 0xffffffffu;
+      return value;
+
+   case GEN_MI_VALUE_TYPE_MEM32:
+      assert(!top_32_bits);
+      return value;
+
+   case GEN_MI_VALUE_TYPE_MEM64:
+      if (top_32_bits)
+         value.addr = __gen_address_offset(value.addr, 4);
+      value.type = GEN_MI_VALUE_TYPE_MEM32;
+      return value;
+
+   case GEN_MI_VALUE_TYPE_REG32:
+      assert(!top_32_bits);
+      return value;
+
+   case GEN_MI_VALUE_TYPE_REG64:
+      if (top_32_bits)
+         value.reg += 4;
+      value.type = GEN_MI_VALUE_TYPE_REG32;
+      return value;
+   }
+
+   unreachable("Invalid gen_mi_value type");
+}
+
+static inline void
+_gen_mi_copy_no_unref(struct gen_mi_builder *b,
+                      struct gen_mi_value dst, struct gen_mi_value src)
+{
+#if GEN_GEN >= 7 || GEN_IS_HASWELL
+   /* TODO: We could handle src.invert by emitting a bit of math if we really
+    * wanted to.
+    */
+   assert(!dst.invert && !src.invert);
+#endif
+   gen_mi_builder_flush_math(b);
+
+   switch (dst.type) {
+   case GEN_MI_VALUE_TYPE_IMM:
+      unreachable("Cannot copy to an immediate");
+
+   case GEN_MI_VALUE_TYPE_MEM64:
+   case GEN_MI_VALUE_TYPE_REG64:
+      /* If the destination is 64 bits, we have to copy in two halves */
+      _gen_mi_copy_no_unref(b, gen_mi_value_half(dst, false),
+                               gen_mi_value_half(src, false));
+      switch (src.type) {
+      case GEN_MI_VALUE_TYPE_IMM:
+      case GEN_MI_VALUE_TYPE_MEM64:
+      case GEN_MI_VALUE_TYPE_REG64:
+         /* TODO: Use MI_STORE_DATA_IMM::StoreQWord when we have it */
+         _gen_mi_copy_no_unref(b, gen_mi_value_half(dst, true),
+                                  gen_mi_value_half(src, true));
+         break;
+      default:
+         _gen_mi_copy_no_unref(b, gen_mi_value_half(dst, true),
+                                  gen_mi_imm(0));
+         break;
+      }
+      break;
+
+   case GEN_MI_VALUE_TYPE_MEM32:
+      switch (src.type) {
+      case GEN_MI_VALUE_TYPE_IMM:
+         gen_mi_builder_emit(b, GENX(MI_STORE_DATA_IMM), sdi) {
+            sdi.Address = dst.addr;
+            sdi.ImmediateData = src.imm;
+         }
+         break;
+
+      case GEN_MI_VALUE_TYPE_MEM32:
+      case GEN_MI_VALUE_TYPE_MEM64:
+#if GEN_GEN >= 8
+         gen_mi_builder_emit(b, GENX(MI_COPY_MEM_MEM), cmm) {
+            cmm.DestinationMemoryAddress = dst.addr;
+            cmm.SourceMemoryAddress = src.addr;
+         }
+#elif GEN_IS_HASWELL
+         {
+            struct gen_mi_value tmp = gen_mi_new_gpr(b);
+            _gen_mi_copy_no_unref(b, tmp, src);
+            _gen_mi_copy_no_unref(b, dst, tmp);
+            gen_mi_value_unref(b, tmp);
+         }
+#else
+         unreachable("Cannot do mem <-> mem copy on IVB and earlier");
+#endif
+         break;
+
+      case GEN_MI_VALUE_TYPE_REG32:
+      case GEN_MI_VALUE_TYPE_REG64:
+         gen_mi_builder_emit(b, GENX(MI_STORE_REGISTER_MEM), srm) {
+            srm.RegisterAddress = src.reg;
+            srm.MemoryAddress = dst.addr;
+         }
+         break;
+
+      default:
+         unreachable("Invalid gen_mi_value type");
+      }
+      break;
+
+   case GEN_MI_VALUE_TYPE_REG32:
+      switch (src.type) {
+      case GEN_MI_VALUE_TYPE_IMM:
+         gen_mi_builder_emit(b, GENX(MI_LOAD_REGISTER_IMM), lri) {
+            lri.RegisterOffset = dst.reg;
+            lri.DataDWord = src.imm;
+         }
+         break;
+
+      case GEN_MI_VALUE_TYPE_MEM32:
+      case GEN_MI_VALUE_TYPE_MEM64:
+         gen_mi_builder_emit(b, GENX(MI_LOAD_REGISTER_MEM), lrm) {
+            lrm.RegisterAddress = dst.reg;
+            lrm.MemoryAddress = src.addr;
+         }
+         break;
+
+      case GEN_MI_VALUE_TYPE_REG32:
+      case GEN_MI_VALUE_TYPE_REG64:
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+         gen_mi_builder_emit(b, GENX(MI_LOAD_REGISTER_REG), lrr) {
+            lrr.SourceRegisterAddress = src.reg;
+            lrr.DestinationRegisterAddress = dst.reg;
+         }
+#else
+         unreachable("Cannot do reg <-> reg copy on IVB and earlier");
+#endif
+         break;
+
+      default:
+         unreachable("Invalid gen_mi_value type");
+      }
+      break;
+
+   default:
+      unreachable("Invalid gen_mi_value type");
+   }
+}
+
+/** Store the value in src to the value represented by dst
+ *
+ * If the bit size of src and dst mismatch, this function does an unsigned
+ * integer cast.  If src has more bits than dst, it takes the bottom bits.  If
+ * src has fewer bits then dst, it fills the top bits with zeros.
+ *
+ * This function consumes one reference for each of src and dst.
+ */
+static inline void
+gen_mi_store(struct gen_mi_builder *b,
+             struct gen_mi_value dst, struct gen_mi_value src)
+{
+   _gen_mi_copy_no_unref(b, dst, src);
+   gen_mi_value_unref(b, src);
+   gen_mi_value_unref(b, dst);
+}
+
+/*
+ * MI_MATH Section.  Only available on Haswell+
+ */
+
+#if GEN_GEN >= 8 || GEN_IS_HASWELL
+
+static inline void
+_gen_mi_builder_push_math(struct gen_mi_builder *b,
+                          const uint32_t *dwords,
+                          unsigned num_dwords)
+{
+   assert(num_dwords < GEN_MI_BUILDER_MAX_MATH_DWORDS);
+   if (b->num_math_dwords + num_dwords > GEN_MI_BUILDER_MAX_MATH_DWORDS)
+      gen_mi_builder_flush_math(b);
+
+   memcpy(&b->math_dwords[b->num_math_dwords],
+          dwords, num_dwords * sizeof(*dwords));
+   b->num_math_dwords += num_dwords;
+}
+
+static inline uint32_t
+_gen_mi_pack_alu(uint32_t opcode, uint32_t operand1, uint32_t operand2)
+{
+   struct GENX(MI_MATH_ALU_INSTRUCTION) instr = {
+      .ALUOpcode = opcode,
+      .Operand1 = operand1,
+      .Operand2 = operand2,
+   };
+
+   uint32_t dw;
+   GENX(MI_MATH_ALU_INSTRUCTION_pack)(NULL, &dw, &instr);
+
+   return dw;
+}
+
+static inline struct gen_mi_value
+gen_mi_value_to_gpr(struct gen_mi_builder *b, struct gen_mi_value val)
+{
+   if (gen_mi_value_is_gpr(val))
+      return val;
+
+   /* Save off the invert flag because it makes copy() grumpy */
+   bool invert = val.invert;
+   val.invert = false;
+
+   struct gen_mi_value tmp = gen_mi_new_gpr(b);
+   _gen_mi_copy_no_unref(b, tmp, val);
+   tmp.invert = invert;
+
+   return tmp;
+}
+
+static inline uint32_t
+_gen_mi_math_load_src(struct gen_mi_builder *b,
+                      unsigned src, struct gen_mi_value *val)
+{
+   if (val->type == GEN_MI_VALUE_TYPE_IMM &&
+       (val->imm == 0 || val->imm == UINT64_MAX)) {
+      uint64_t imm = val->invert ? ~val->imm : val->imm;
+      return _gen_mi_pack_alu(imm ? MI_ALU_LOAD1 : MI_ALU_LOAD0, src, 0);
+   } else {
+      *val = gen_mi_value_to_gpr(b, *val);
+      return _gen_mi_pack_alu(val->invert ? MI_ALU_LOADINV : MI_ALU_LOAD,
+                              src, _gen_mi_value_as_gpr(*val));
+   }
+}
+
+static inline struct gen_mi_value
+gen_mi_math_binop(struct gen_mi_builder *b, uint32_t opcode,
+                  struct gen_mi_value src0, struct gen_mi_value src1,
+                  uint32_t store_op, uint32_t store_src)
+{
+   struct gen_mi_value dst = gen_mi_new_gpr(b);
+
+   uint32_t dw[4];
+   dw[0] = _gen_mi_math_load_src(b, MI_ALU_SRCA, &src0);
+   dw[1] = _gen_mi_math_load_src(b, MI_ALU_SRCB, &src1);
+   dw[2] = _gen_mi_pack_alu(opcode, 0, 0);
+   dw[3] = _gen_mi_pack_alu(store_op, _gen_mi_value_as_gpr(dst), store_src);
+   _gen_mi_builder_push_math(b, dw, 4);
+
+   gen_mi_value_unref(b, src0);
+   gen_mi_value_unref(b, src1);
+
+   return dst;
+}
+
+static inline struct gen_mi_value
+gen_mi_inot(struct gen_mi_builder *b, struct gen_mi_value val)
+{
+   /* TODO These currently can't be passed into gen_mi_copy */
+   val.invert = !val.invert;
+   return val;
+}
+
+static inline struct gen_mi_value
+gen_mi_iadd(struct gen_mi_builder *b,
+            struct gen_mi_value src0, struct gen_mi_value src1)
+{
+   return gen_mi_math_binop(b, MI_ALU_ADD, src0, src1,
+                            MI_ALU_STORE, MI_ALU_ACCU);
+}
+
+static inline struct gen_mi_value
+gen_mi_iadd_imm(struct gen_mi_builder *b,
+                struct gen_mi_value src, uint64_t N)
+{
+   if (N == 0)
+      return src;
+
+   return gen_mi_iadd(b, src, gen_mi_imm(N));
+}
+
+static inline struct gen_mi_value
+gen_mi_isub(struct gen_mi_builder *b,
+            struct gen_mi_value src0, struct gen_mi_value src1)
+{
+   return gen_mi_math_binop(b, MI_ALU_SUB, src0, src1,
+                            MI_ALU_STORE, MI_ALU_ACCU);
+}
+
+static inline struct gen_mi_value
+gen_mi_ult(struct gen_mi_builder *b,
+           struct gen_mi_value src0, struct gen_mi_value src1)
+{
+   /* Compute "less than" by subtracting and storing the carry bit */
+   return gen_mi_math_binop(b, MI_ALU_SUB, src0, src1,
+                            MI_ALU_STORE, MI_ALU_CF);
+}
+
+static inline struct gen_mi_value
+gen_mi_uge(struct gen_mi_builder *b,
+           struct gen_mi_value src0, struct gen_mi_value src1)
+{
+   /* Compute "less than" by subtracting and storing the carry bit */
+   return gen_mi_math_binop(b, MI_ALU_SUB, src0, src1,
+                            MI_ALU_STOREINV, MI_ALU_CF);
+}
+
+static inline struct gen_mi_value
+gen_mi_iand(struct gen_mi_builder *b,
+            struct gen_mi_value src0, struct gen_mi_value src1)
+{
+   return gen_mi_math_binop(b, MI_ALU_AND, src0, src1,
+                            MI_ALU_STORE, MI_ALU_ACCU);
+}
+
+static inline struct gen_mi_value
+gen_mi_imul_imm(struct gen_mi_builder *b,
+                struct gen_mi_value src, uint32_t N)
+{
+   if (N == 0) {
+      gen_mi_value_unref(b, src);
+      return gen_mi_imm(0);
+   }
+
+   if (N == 1)
+      return src;
+
+   src = gen_mi_value_to_gpr(b, src);
+
+   struct gen_mi_value res = gen_mi_value_ref(b, src);
+
+   unsigned top_bit = 31 - __builtin_clz(N);
+   for (int i = top_bit - 1; i >= 0; i--) {
+      res = gen_mi_iadd(b, res, gen_mi_value_ref(b, res));
+      if (N & (1 << i))
+         res = gen_mi_iadd(b, res, gen_mi_value_ref(b, src));
+   }
+
+   gen_mi_value_unref(b, src);
+
+   return res;
+}
+
+static inline struct gen_mi_value
+gen_mi_ishl_imm(struct gen_mi_builder *b,
+                struct gen_mi_value src, uint32_t shift)
+{
+   struct gen_mi_value res = gen_mi_value_to_gpr(b, src);
+
+   for (unsigned i = 0; i < shift; i++)
+      res = gen_mi_iadd(b, res, gen_mi_value_ref(b, res));
+
+   return res;
+}
+
+static inline struct gen_mi_value
+gen_mi_ushr32_imm(struct gen_mi_builder *b,
+                  struct gen_mi_value src, uint32_t shift)
+{
+   /* We right-shift by left-shifting by 32 - shift and taking the top 32 bits
+    * of the result.  This assumes the top 32 bits are zero.
+    */
+   assert(shift <= 32);
+   struct gen_mi_value tmp = gen_mi_ishl_imm(b, src, 32 - shift);
+   struct gen_mi_value dst = gen_mi_new_gpr(b);
+   _gen_mi_copy_no_unref(b, gen_mi_value_half(dst, false),
+                            gen_mi_value_half(tmp, true));
+   _gen_mi_copy_no_unref(b, gen_mi_value_half(dst, true), gen_mi_imm(0));
+   gen_mi_value_unref(b, tmp);
+   return dst;
+}
+
+static inline struct gen_mi_value
+gen_mi_udiv32_imm(struct gen_mi_builder *b,
+                  struct gen_mi_value N, uint32_t D)
+{
+   /* We implicitly assume that N is only a 32-bit value */
+   if (D == 0) {
+      /* This is invalid but we should do something */
+      return gen_mi_imm(0);
+   } else if (util_is_power_of_two_or_zero(D)) {
+      return gen_mi_ushr32_imm(b, N, util_logbase2(D));
+   } else {
+      struct util_fast_udiv_info m = util_compute_fast_udiv_info(D, 32, 32);
+      assert(m.multiplier <= UINT32_MAX);
+
+      if (m.pre_shift)
+         N = gen_mi_ushr32_imm(b, N, m.pre_shift);
+
+      /* Do the 32x32 multiply  into gpr0 */
+      N = gen_mi_imul_imm(b, N, m.multiplier);
+
+      if (m.increment)
+         N = gen_mi_iadd(b, N, gen_mi_imm(m.multiplier));
+
+      N = gen_mi_ushr32_imm(b, N, 32);
+
+      if (m.post_shift)
+         N = gen_mi_ushr32_imm(b, N, m.post_shift);
+
+      return N;
+   }
+}
+
+#endif /* MI_MATH section */
+
+#endif /* GEN_MI_BUILDER_H */