nouveau/mme: Add a bfe helper

This extracts a fixed number of bits from a possibly variable position
in the source value.  Very helpful for testing for a bit.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24326>

src/nouveau/mme/mme_builder.h

@@ -342,6 +342,29 @@ mme_mul64(struct mme_builder *b,
    return dst;
 }
 
+static inline void
+mme_bfe_to(struct mme_builder *b, struct mme_value dst,
+           struct mme_value x, struct mme_value pos, uint8_t bits)
+{
+   if (b->devinfo->cls_eng3d >= MME_CLS_TURING) {
+      mme_srl_to(b, dst, x, pos);
+      mme_and_to(b, dst, dst, mme_imm(BITFIELD_MASK(bits)));
+   } else if (b->devinfo->cls_eng3d >= MME_CLS_FERMI) {
+      mme_fermi_bfe_to(b, dst, x, pos, bits);
+   } else {
+      unreachable("Unsupported GPU class");
+   }
+}
+
+static inline struct mme_value
+mme_bfe(struct mme_builder *b,
+        struct mme_value x, struct mme_value pos, uint8_t bits)
+{
+   struct mme_value dst = mme_alloc_reg(b);
+   mme_bfe_to(b, dst, x, pos, bits);
+   return dst;
+}
+
 static inline void
 mme_merge_to(struct mme_builder *b, struct mme_value dst,
              struct mme_value x, struct mme_value y,

src/nouveau/mme/mme_fermi_builder.c

@@ -309,6 +309,16 @@ mme_fermi_srl_to(struct mme_fermi_builder *b,
    mme_fermi_bfe(b, dst, y, x, mme_zero(), 31);
 }
 
+void
+mme_fermi_bfe_to(struct mme_builder *b, struct mme_value dst,
+                 struct mme_value x, struct mme_value pos, uint8_t bits)
+{
+   struct mme_fermi_builder *fb = &b->fermi;
+   assert(mme_fermi_is_zero_or_reg(dst));
+
+   mme_fermi_bfe(fb, dst, pos, x, mme_zero(), bits);
+}
+
 static struct mme_value
 mme_fermi_load_imm_to_reg(struct mme_builder *b, struct mme_value data)
 {

src/nouveau/mme/mme_fermi_builder.h

@@ -101,6 +101,10 @@ mme_fermi_alu64_to(struct mme_builder *b,
    mme_fermi_alu_to(b, dst.hi, op_hi, x.hi, y.hi);
 }
 
+void
+mme_fermi_bfe_to(struct mme_builder *b, struct mme_value dst,
+                 struct mme_value x, struct mme_value pos, uint8_t bits);
+
 void
 mme_fermi_merge_to(struct mme_builder *b, struct mme_value dst,
                    struct mme_value x, struct mme_value y,

src/nouveau/mme/tests/mme_fermi_sim_hw_test.cpp

@@ -357,6 +357,35 @@ SHIFT_TEST(srl)
 
 #undef SHIFT_TEST
 
+TEST_F(mme_fermi_sim_test, bfe)
+{
+   const uint32_t canary = 0xc0ffee01;
+
+   mme_builder b;
+   mme_builder_init(&b, devinfo);
+
+   mme_value val = mme_load(&b);
+   mme_value pos = mme_load(&b);
+
+   mme_store_imm_addr(&b, data_addr + 0, mme_bfe(&b, val, pos, 1), true);
+   mme_store_imm_addr(&b, data_addr + 4, mme_bfe(&b, val, pos, 2), true);
+   mme_store_imm_addr(&b, data_addr + 8, mme_bfe(&b, val, pos, 5), true);
+
+   auto macro = mme_builder_finish_vec(&b);
+
+   for (unsigned i = 0; i < 31; i++) {
+      std::vector<uint32_t> params;
+      params.push_back(canary);
+      params.push_back(i);
+
+      test_macro(&b, macro, params);
+
+      ASSERT_EQ(data[0], (canary >> i) & 0x1);
+      ASSERT_EQ(data[1], (canary >> i) & 0x3);
+      ASSERT_EQ(data[2], (canary >> i) & 0x1f);
+   }
+}
+
 #define BITOP_TEST(op)                                   \
 TEST_F(mme_fermi_sim_test, op)                           \
 {                                                        \

src/nouveau/mme/tests/mme_tu104_sim_hw_test.cpp

@@ -876,6 +876,35 @@ SHIFT_TEST(sra)
 
 #undef SHIFT_TEST
 
+TEST_F(mme_tu104_sim_test, bfe)
+{
+   const uint32_t canary = 0xc0ffee01;
+
+   mme_builder b;
+   mme_builder_init(&b, devinfo);
+
+   mme_value val = mme_load(&b);
+   mme_value pos = mme_load(&b);
+
+   mme_store_imm_addr(&b, data_addr + 0, mme_bfe(&b, val, pos, 1), true);
+   mme_store_imm_addr(&b, data_addr + 4, mme_bfe(&b, val, pos, 2), true);
+   mme_store_imm_addr(&b, data_addr + 8, mme_bfe(&b, val, pos, 5), true);
+
+   auto macro = mme_builder_finish_vec(&b);
+
+   for (unsigned i = 0; i < 31; i++) {
+      std::vector<uint32_t> params;
+      params.push_back(canary);
+      params.push_back(i);
+
+      test_macro(&b, macro, params);
+
+      ASSERT_EQ(data[0], (canary >> i) & 0x1);
+      ASSERT_EQ(data[1], (canary >> i) & 0x3);
+      ASSERT_EQ(data[2], (canary >> i) & 0x1f);
+   }
+}
+
 #define BITOP_TEST(op)                                               \
 TEST_F(mme_tu104_sim_test, op)                                       \
 {                                                                    \