Mesa (master): nvc0/ir: don' t require AND when the high byte is being addressed

[Ilia Mirkin]

Module: Mesa
Branch: master
Commit: 9ebe7dc09479d9a8df2733ef96525a2b5e758f6d
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=9ebe7dc09479d9a8df2733ef96525a2b5e758f6d

Author: Ilia Mirkin <imirkin at alum.mit.edu>
Date:   Tue Aug 18 22:53:11 2015 -0400

nvc0/ir: don't require AND when the high byte is being addressed

unpackUnorm* lowering doesn't AND the high byte/word as it's
unnecessary. Detect that situation as well.

Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>

---

 src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
index ef286c0..cf83c19 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
@@ -1532,6 +1532,7 @@ AlgebraicOpt::handleCVT_NEG(Instruction *cvt)
 // CVT(EXTBF(x, byte/word))
 // CVT(AND(bytemask, x))
 // CVT(AND(bytemask, SHR(x, 8/16/24)))
+// CVT(SHR(x, 16/24))
 void
 AlgebraicOpt::handleCVT_EXTBF(Instruction *cvt)
 {
@@ -1578,6 +1579,17 @@ AlgebraicOpt::handleCVT_EXTBF(Instruction *cvt)
          arg = shift->getSrc(0);
          offset = imm1.reg.data.u32;
       }
+   } else if (insn->op == OP_SHR && insn->src(1).getImmediate(imm0)) {
+      arg = insn->getSrc(0);
+      if (imm0.reg.data.u32 == 24) {
+         width = 8;
+         offset = 24;
+      } else if (imm0.reg.data.u32 == 16) {
+         width = 16;
+         offset = 16;
+      } else {
+         return;
+      }
    }
 
    if (!arg)