[Mesa-dev] [PATCH v2 02/19] i965/fs: Actually set/use the mlen for gen7 uniform pull constant loads

[Jason Ekstrand]

Previously, we were allocating the payload with different sizes per gen and
then figuring out the mlen in the generator based on gen.  This meant,
among other things, that the higher level passes knew nothing about it.
---
 src/mesa/drivers/dri/i965/brw_fs.cpp           | 19 ++++++++++++-------
 src/mesa/drivers/dri/i965/brw_fs_generator.cpp |  9 +++------
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 3ec8e6a..31dfb24 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -2909,14 +2909,18 @@ fs_visitor::lower_uniform_pull_constant_loads()
          assert(const_offset_reg.file == IMM &&
                 const_offset_reg.type == BRW_REGISTER_TYPE_UD);
          const_offset_reg.fixed_hw_reg.dw1.ud /= 4;
-         fs_reg payload = fs_reg(GRF, alloc.allocate(1));
 
-         /* We have to use a message header on Skylake to get SIMD4x2 mode.
-          * Reserve space for the register.
-          */
+         fs_reg payload, offset;
          if (devinfo->gen >= 9) {
-            payload.reg_offset++;
-            alloc.sizes[payload.reg] = 2;
+            /* We have to use a message header on Skylake to get SIMD4x2
+             * mode.  Reserve space for the register.
+            */
+            offset = payload = fs_reg(GRF, alloc.allocate(2));
+            offset.reg_offset++;
+            inst->mlen = 2;
+         } else {
+            offset = payload = fs_reg(GRF, alloc.allocate(1));
+            inst->mlen = 1;
          }
 
          /* This is actually going to be a MOV, but since only the first dword
@@ -2925,7 +2929,7 @@ fs_visitor::lower_uniform_pull_constant_loads()
           * by live variable analysis, or register allocation will explode.
           */
          fs_inst *setup = new(mem_ctx) fs_inst(FS_OPCODE_SET_SIMD4X2_OFFSET,
-                                               8, payload, const_offset_reg);
+                                               8, offset, const_offset_reg);
          setup->force_writemask_all = true;
 
          setup->ir = inst->ir;
@@ -2938,6 +2942,7 @@ fs_visitor::lower_uniform_pull_constant_loads()
           */
          inst->opcode = FS_OPCODE_UNIFORM_PULL_CONSTANT_LOAD_GEN7;
          inst->src[1] = payload;
+         inst->base_mrf = -1;
 
          invalidate_live_intervals();
       } else {
diff --git a/src/mesa/drivers/dri/i965/brw_fs_generator.cpp b/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
index 2ed0bac..8d821ab 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_generator.cpp
@@ -1054,7 +1054,6 @@ fs_generator::generate_uniform_pull_constant_load_gen7(fs_inst *inst,
                                                        struct brw_reg index,
                                                        struct brw_reg offset)
 {
-   assert(inst->mlen == 0);
    assert(index.type == BRW_REGISTER_TYPE_UD);
 
    assert(offset.file == BRW_GENERAL_REGISTER_FILE);
@@ -1069,12 +1068,10 @@ fs_generator::generate_uniform_pull_constant_load_gen7(fs_inst *inst,
 
    struct brw_reg src = offset;
    bool header_present = false;
-   int mlen = 1;
 
    if (devinfo->gen >= 9) {
       /* Skylake requires a message header in order to use SIMD4x2 mode. */
-      src = retype(brw_vec4_grf(offset.nr - 1, 0), BRW_REGISTER_TYPE_UD);
-      mlen = 2;
+      src = retype(brw_vec4_grf(offset.nr, 0), BRW_REGISTER_TYPE_UD);
       header_present = true;
 
       brw_push_insn_state(p);
@@ -1105,7 +1102,7 @@ fs_generator::generate_uniform_pull_constant_load_gen7(fs_inst *inst,
                               0, /* LD message ignores sampler unit */
                               GEN5_SAMPLER_MESSAGE_SAMPLE_LD,
                               1, /* rlen */
-                              mlen,
+                              inst->mlen,
                               header_present,
                               BRW_SAMPLER_SIMD_MODE_SIMD4X2,
                               0);
@@ -1135,7 +1132,7 @@ fs_generator::generate_uniform_pull_constant_load_gen7(fs_inst *inst,
                               0, /* LD message ignores sampler unit */
                               GEN5_SAMPLER_MESSAGE_SAMPLE_LD,
                               1, /* rlen */
-                              mlen,
+                              inst->mlen,
                               header_present,
                               BRW_SAMPLER_SIMD_MODE_SIMD4X2,
                               0);
-- 
2.4.3