nir: Drop "SSA" from NIR language

Everything is SSA now.

   sed -e 's/nir_ssa_def/nir_def/g' \
       -e 's/nir_ssa_undef/nir_undef/g' \
       -e 's/nir_ssa_scalar/nir_scalar/g' \
       -e 's/nir_src_rewrite_ssa/nir_src_rewrite/g' \
       -e 's/nir_gather_ssa_types/nir_gather_types/g' \
       -i $(git grep -l nir | grep -v relnotes)

   git mv src/compiler/nir/nir_gather_ssa_types.c \
          src/compiler/nir/nir_gather_types.c

   ninja -C build/ clang-format
   cd src/compiler/nir && find *.c *.h -type f -exec clang-format -i \{} \;

Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Acked-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Acked-by: Emma Anholt <emma@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24585>

src/imagination/rogue/nir/rogue_nir_lower_io.c

@@ -45,11 +45,11 @@ static void lower_vulkan_resource_index(nir_builder *b,
    unsigned binding = nir_intrinsic_binding(intr);
    unsigned desc_type = nir_intrinsic_desc_type(intr);
 
-   nir_ssa_def *def = nir_vec3(b,
+   nir_def *def = nir_vec3(b,
                                nir_imm_int(b, desc_set),
                                nir_imm_int(b, binding),
                                nir_imm_int(b, desc_type));
-   nir_ssa_def_rewrite_uses(&intr->dest.ssa, def);
+   nir_def_rewrite_uses(&intr->dest.ssa, def);
    nir_instr_remove(&intr->instr);
 }
 
@@ -61,7 +61,7 @@ static void lower_load_global_constant_to_scalar(nir_builder *b,
 
    assert(intr->num_components > 1);
 
-   nir_ssa_def *loads[NIR_MAX_VEC_COMPONENTS];
+   nir_def *loads[NIR_MAX_VEC_COMPONENTS];
 
    for (uint8_t i = 0; i < intr->num_components; i++) {
       nir_intrinsic_instr *chan_intr =
@@ -86,7 +86,7 @@ static void lower_load_global_constant_to_scalar(nir_builder *b,
       loads[i] = &chan_intr->dest.ssa;
    }
 
-   nir_ssa_def_rewrite_uses(&intr->dest.ssa,
+   nir_def_rewrite_uses(&intr->dest.ssa,
                             nir_vec(b, loads, intr->num_components));
    nir_instr_remove(&intr->instr);
 }

src/imagination/rogue/nir/rogue_nir_pfo.c

@@ -41,7 +41,7 @@ static void insert_pfo(nir_builder *b,
    /* TODO: Verify type is vec4. */
 
    /* Pack the output color components into U8888 format. */
-   nir_ssa_def *new_output_src_ssa = nir_pack_unorm_4x8(b, output_src->ssa);
+   nir_def *new_output_src_ssa = nir_pack_unorm_4x8(b, output_src->ssa);
    nir_src new_output_src = nir_src_for_ssa(new_output_src_ssa);
 
    /* Update the store_output intrinsic. */

src/imagination/rogue/rogue_compile.c

@@ -723,7 +723,7 @@ static inline void rogue_feedback_used_regs(rogue_build_ctx *ctx,
       rogue_count_used_regs(shader, ROGUE_REG_CLASS_INTERNAL);
 }
 
-static bool ssa_def_cb(nir_ssa_def *ssa, void *state)
+static bool ssa_def_cb(nir_def *ssa, void *state)
 {
    rogue_shader *shader = (rogue_shader *)state;