i965: Remove writemask support from brw_SAMPLE().

The code was rather broken for non-XYZW on 8-wide, but all of our
callers were using XYZW anyway.  For my experiments with using writemask
on texturing, I've been using manual header setup in the compiler
backends, since we want to actually know what registers are written for
optimization and register allocation.

Reviewed-by: Kenneth Graunke <[email protected]>

5 files changed, 18 insertions, 109 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
index 3615b097cef..fd004891c80 100644
--- a/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_blorp_blit.cpp
@@ -1617,7 +1617,6 @@ brw_blorp_blit_program::texture_lookup(struct brw_reg dst,
               brw_message_reg(base_mrf) /* src0 */,
               BRW_BLORP_TEXTURE_BINDING_TABLE_INDEX,
               0 /* sampler */,
-              WRITEMASK_XYZW,
               msg_type,
               8 /* response_length.  TODO: should be smaller for non-RGBA formats? */,
               mrf.nr - base_mrf /* msg_length */,
diff --git a/src/mesa/drivers/dri/i965/brw_eu.h b/src/mesa/drivers/dri/i965/brw_eu.h
index 06daabac9bd..adb3c4d29ec 100644
--- a/src/mesa/drivers/dri/i965/brw_eu.h
+++ b/src/mesa/drivers/dri/i965/brw_eu.h
@@ -265,7 +265,6 @@ void brw_SAMPLE(struct brw_compile *p,
 		struct brw_reg src0,
 		GLuint binding_table_index,
 		GLuint sampler,
-		GLuint writemask,
 		GLuint msg_type,
 		GLuint response_length,
 		GLuint msg_length,
diff --git a/src/mesa/drivers/dri/i965/brw_eu_emit.c b/src/mesa/drivers/dri/i965/brw_eu_emit.c
index b34754a9cfc..f2dcbeb1f26 100644
--- a/src/mesa/drivers/dri/i965/brw_eu_emit.c
+++ b/src/mesa/drivers/dri/i965/brw_eu_emit.c
@@ -2124,7 +2124,6 @@ void brw_SAMPLE(struct brw_compile *p,
 		struct brw_reg src0,
 		GLuint binding_table_index,
 		GLuint sampler,
-		GLuint writemask,
 		GLuint msg_type,
 		GLuint response_length,
 		GLuint msg_length,
@@ -2133,113 +2132,27 @@ void brw_SAMPLE(struct brw_compile *p,
 		GLuint return_format)
 {
    struct intel_context *intel = &p->brw->intel;
-   bool need_stall = 0;
-
-   if (writemask == 0) {
-      /*printf("%s: zero writemask??\n", __FUNCTION__); */
-      return;
-   }
-   
-   /* Hardware doesn't do destination dependency checking on send
-    * instructions properly.  Add a workaround which generates the
-    * dependency by other means.  In practice it seems like this bug
-    * only crops up for texture samples, and only where registers are
-    * written by the send and then written again later without being
-    * read in between.  Luckily for us, we already track that
-    * information and use it to modify the writemask for the
-    * instruction, so that is a guide for whether a workaround is
-    * needed.
-    */
-   if (writemask != WRITEMASK_XYZW) {
-      GLuint dst_offset = 0;
-      GLuint i, newmask = 0, len = 0;
-
-      for (i = 0; i < 4; i++) {
-	 if (writemask & (1<<i))
-	    break;
-	 dst_offset += 2;
-      }
-      for (; i < 4; i++) {
-	 if (!(writemask & (1<<i)))
-	    break;
-	 newmask |= 1<<i;
-	 len++;
-      }
-
-      if (newmask != writemask) {
-	 need_stall = 1;
-         /* printf("need stall %x %x\n", newmask , writemask); */
-      }
-      else {
-	 bool dispatch_16 = false;
-
-	 struct brw_reg m1 = brw_message_reg(msg_reg_nr);
-
-	 guess_execution_size(p, p->current, dest);
-	 if (p->current->header.execution_size == BRW_EXECUTE_16)
-	    dispatch_16 = true;
-
-	 newmask = ~newmask & WRITEMASK_XYZW;
-
-	 brw_push_insn_state(p);
-
-	 brw_set_compression_control(p, BRW_COMPRESSION_NONE);
-	 brw_set_mask_control(p, BRW_MASK_DISABLE);
-
-	 brw_MOV(p, retype(m1, BRW_REGISTER_TYPE_UD),
-		 retype(brw_vec8_grf(0,0), BRW_REGISTER_TYPE_UD));
-  	 brw_MOV(p, get_element_ud(m1, 2), brw_imm_ud(newmask << 12)); 
-
-	 brw_pop_insn_state(p);
-
-  	 src0 = retype(brw_null_reg(), BRW_REGISTER_TYPE_UW); 
-	 dest = offset(dest, dst_offset);
-
-	 /* For 16-wide dispatch, masked channels are skipped in the
-	  * response.  For 8-wide, masked channels still take up slots,
-	  * and are just not written to.
-	  */
-	 if (dispatch_16)
-	    response_length = len * 2;
-      }
-   }
-
-   {
-      struct brw_instruction *insn;
-   
-      gen6_resolve_implied_move(p, &src0, msg_reg_nr);
+   struct brw_instruction *insn;
 
-      insn = next_insn(p, BRW_OPCODE_SEND);
-      insn->header.predicate_control = 0; /* XXX */
-      insn->header.compression_control = BRW_COMPRESSION_NONE;
-      if (intel->gen < 6)
-	  insn->header.destreg__conditionalmod = msg_reg_nr;
+   gen6_resolve_implied_move(p, &src0, msg_reg_nr);
 
-      brw_set_dest(p, insn, dest);
-      brw_set_src0(p, insn, src0);
-      brw_set_sampler_message(p, insn,
-			      binding_table_index,
-			      sampler,
-			      msg_type,
-			      response_length, 
-			      msg_length,
-			      header_present,
-			      simd_mode,
-			      return_format);
-   }
-
-   if (need_stall) {
-      struct brw_reg reg = vec8(offset(dest, response_length-1));
-
-      /*  mov (8) r9.0<1>:f    r9.0<8;8,1>:f    { Align1 }
-       */
-      brw_push_insn_state(p);
-      brw_set_compression_control(p, BRW_COMPRESSION_NONE);
-      brw_MOV(p, retype(reg, BRW_REGISTER_TYPE_UD),
-	      retype(reg, BRW_REGISTER_TYPE_UD));
-      brw_pop_insn_state(p);
-   }
+   insn = next_insn(p, BRW_OPCODE_SEND);
+   insn->header.predicate_control = 0; /* XXX */
+   insn->header.compression_control = BRW_COMPRESSION_NONE;
+   if (intel->gen < 6)
+      insn->header.destreg__conditionalmod = msg_reg_nr;
 
+   brw_set_dest(p, insn, dest);
+   brw_set_src0(p, insn, src0);
+   brw_set_sampler_message(p, insn,
+                           binding_table_index,
+                           sampler,
+                           msg_type,
+                           response_length,
+                           msg_length,
+                           header_present,
+                           simd_mode,
+                           return_format);
 }
 
 /* All these variables are pretty confusing - we might be better off
diff --git a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
index 76446523cb1..62e57c98188 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_emit.cpp
@@ -491,7 +491,6 @@ fs_generator::generate_tex(fs_inst *inst, struct brw_reg dst, struct brw_reg src
 	      src,
               SURF_INDEX_TEXTURE(inst->sampler),
 	      inst->sampler,
-	      WRITEMASK_XYZW,
 	      msg_type,
 	      rlen,
 	      inst->mlen,
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
index 863ff7ce02b..cc2f5d4c8b0 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
@@ -372,7 +372,6 @@ vec4_generator::generate_tex(vec4_instruction *inst,
 	      src,
 	      SURF_INDEX_VS_TEXTURE(inst->sampler),
 	      inst->sampler,
-	      WRITEMASK_XYZW,
 	      msg_type,
 	      1, /* response length */
 	      inst->mlen,