Mesa (master): i965: Don't emit register spill offsets directly into g0.

[Eric Anholt]

Module: Mesa
Branch: master
Commit: 0b77d57394a3712851ec271aa7ad353d56f302a1
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=0b77d57394a3712851ec271aa7ad353d56f302a1

Author: Eric Anholt <eric at anholt.net>
Date:   Thu Oct 21 14:40:49 2010 -0700

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.

---

 src/mesa/drivers/dri/i965/brw_eu_emit.c |   28 ++++++++++++++++++++++------
 1 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_eu_emit.c b/src/mesa/drivers/dri/i965/brw_eu_emit.c
index 63ab5c2..6fbc396 100644
--- 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,