Mesa (master): gk110/ir: do not overwrite def value with zero for EXCH ops

[Samuel Pitoiset]

Module: Mesa
Branch: master
Commit: 17a37c78fc16505f717a44aa22551285d1cd8c9e
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=17a37c78fc16505f717a44aa22551285d1cd8c9e

Author: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Date:   Wed Apr 20 19:47:37 2016 +0200

gk110/ir: do not overwrite def value with zero for EXCH ops

This is only valid for other atomic operations (including CAS). This
fixes an invalid opcode error from dmesg. While we are it, make sure
to initialize global addr to 0 for other atomic operations.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Reviewed-by: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: "11.1 11.2" <mesa-stable at lists.freedesktop.org>

---

 .../drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp  | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp
index 70f3c3f..e2c3b8e 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_emit_gk110.cpp
@@ -1808,6 +1808,9 @@ uses64bitAddress(const Instruction *ldst)
 void
 CodeEmitterGK110::emitATOM(const Instruction *i)
 {
+   const bool hasDst = i->defExists(0);
+   const bool exch = i->subOp == NV50_IR_SUBOP_ATOM_EXCH;
+
    code[0] = 0x00000002;
    if (i->subOp == NV50_IR_SUBOP_ATOM_CAS)
       code[1] = 0x77800000;
@@ -1836,15 +1839,21 @@ CodeEmitterGK110::emitATOM(const Instruction *i)
    /* TODO: cas: flip bits if $r255 is used */
    srcId(i->src(1), 23);
 
-   if (i->defExists(0))
+   if (hasDst) {
       defId(i->def(0), 2);
-   else
+   } else
+   if (!exch) {
       code[0] |= 255 << 2;
+   }
 
-   const int32_t offset = SDATA(i->src(0)).offset;
-   assert(offset < 0x80000 && offset >= -0x80000);
-   code[0] |= (offset & 1) << 31;
-   code[1] |= (offset & 0xffffe) >> 1;
+   if (hasDst || !exch) {
+      const int32_t offset = SDATA(i->src(0)).offset;
+      assert(offset < 0x80000 && offset >= -0x80000);
+      code[0] |= (offset & 1) << 31;
+      code[1] |= (offset & 0xffffe) >> 1;
+   } else {
+      srcAddr32(i->src(0), 31);
+   }
 
    if (i->getIndirect(0, 0)) {
       srcId(i->getIndirect(0, 0), 10);