i965: Don't emit register spill offsets directly into g0.

g0 is used by others, and is expected to be left exactly as it was
dispatched to us.  So manually move g0 into our message reg when
spilling/unspilling and update the offset in the MRF.  Fixes failures
in texture sampling after having spilled a register.

diff --git a/src/mesa/drivers/dri/i965/brw_eu_emit.c b/src/mesa/drivers/dri/i965/brw_eu_emit.c
index 63ab5c26f36b908f7b300acdf8ac23750f174a05..6fbc39672f11d57a824e212e955b50a36fae132a 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_eu_emit.c
+++ b/src/mesa/drivers/dri/i965/brw_eu_emit.c
@@ -1368,6 +1368,8 @@ void brw_oword_block_write(struct brw_compile *p,
    uint32_t msg_control;
    int mlen;
 
+   mrf = retype(mrf, BRW_REGISTER_TYPE_UD);
+
    if (num_regs == 1) {
       msg_control = BRW_DATAPORT_OWORD_BLOCK_2_OWORDS;
       mlen = 2;
@@ -1376,15 +1378,24 @@ void brw_oword_block_write(struct brw_compile *p,
       mlen = 3;
    }
 
+   /* Set up the message header.  This is g0, with g0.2 filled with
+    * the offset.  We don't want to leave our offset around in g0 or
+    * it'll screw up texture samples, so set it up inside the message
+    * reg.
+    */
    {
       brw_push_insn_state(p);
       brw_set_mask_control(p, BRW_MASK_DISABLE);
       brw_set_compression_control(p, BRW_COMPRESSION_NONE);
 
+      brw_MOV(p, mrf, retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UD));
+
       /* set message header global offset field (reg 0, element 2) */
       brw_MOV(p,
-             retype(brw_vec1_grf(0, 2), BRW_REGISTER_TYPE_D),
-             brw_imm_d(offset));
+             retype(brw_vec1_reg(BRW_MESSAGE_REGISTER_FILE,
+                                 mrf.nr,
+                                 2), BRW_REGISTER_TYPE_UD),
+             brw_imm_ud(offset));
 
       brw_pop_insn_state(p);
    }
@@ -1422,7 +1433,7 @@ void brw_oword_block_write(struct brw_compile *p,
       }
 
       brw_set_dest(insn, dest);
-      brw_set_src0(insn, src_header);
+      brw_set_src0(insn, brw_null_reg());
 
       brw_set_dp_write_message(p->brw,
                               insn,
@@ -1456,6 +1467,7 @@ brw_oword_block_read(struct brw_compile *p,
    uint32_t msg_control;
    int rlen;
 
+   mrf = retype(mrf, BRW_REGISTER_TYPE_UD);
    dest = retype(dest, BRW_REGISTER_TYPE_UW);
 
    if (num_regs == 1) {
@@ -1471,10 +1483,14 @@ brw_oword_block_read(struct brw_compile *p,
       brw_set_compression_control(p, BRW_COMPRESSION_NONE);
       brw_set_mask_control(p, BRW_MASK_DISABLE);
 
+      brw_MOV(p, mrf, retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UD));
+
       /* set message header global offset field (reg 0, element 2) */
       brw_MOV(p,
-             retype(brw_vec1_grf(0, 2), BRW_REGISTER_TYPE_D),
-             brw_imm_d(offset));
+             retype(brw_vec1_reg(BRW_MESSAGE_REGISTER_FILE,
+                                 mrf.nr,
+                                 2), BRW_REGISTER_TYPE_UD),
+             brw_imm_ud(offset));
 
       brw_pop_insn_state(p);
    }
@@ -1487,7 +1503,7 @@ brw_oword_block_read(struct brw_compile *p,
       insn->header.destreg__conditionalmod = mrf.nr;
 
       brw_set_dest(insn, dest);        /* UW? */
-      brw_set_src0(insn, retype(brw_vec8_grf(0, 0), BRW_REGISTER_TYPE_UW));
+      brw_set_src0(insn, brw_null_reg());
 
       brw_set_dp_read_message(p->brw,
                              insn,