[Mesa-dev] [PATCH] nvc0/ir: fix robustness guarantees for constbuf loads on kepler+ compute

[Ilia Mirkin]

Kepler and up unfortunately only support up to 8 constbufs. We work
around this by loading from constbufs as if they were storage buffers.
However we were not consistently applying limits to loads from these
buffers. Make sure to do the same thing we do for storage buffers.

Fixes GL45-CTS.robust_buffer_access_behavior.uniform_buffer

Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
---
 .../nouveau/codegen/nv50_ir_lowering_nvc0.cpp      | 46 ++++++++++------------
 1 file changed, 21 insertions(+), 25 deletions(-)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.cpp
index cbea468..b3008b3 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.cpp
@@ -2289,32 +2289,28 @@ NVC0LoweringPass::handleLDST(Instruction *i)
                              bld.loadImm(NULL, 12));
          }
 
-         if (i->src(0).isIndirect(1)) {
-            Value *offset = bld.loadImm(NULL, i->getSrc(0)->reg.data.offset + typeSizeof(i->sType));
-            Value *ptr = loadUboInfo64(ind, fileIndex * 16);
-            Value *length = loadUboLength32(ind, fileIndex * 16);
-            Value *pred = new_LValue(func, FILE_PREDICATE);
-            if (i->src(0).isIndirect(0)) {
-               bld.mkOp2(OP_ADD, TYPE_U64, ptr, ptr, i->getIndirect(0, 0));
-               bld.mkOp2(OP_ADD, TYPE_U32, offset, offset, i->getIndirect(0, 0));
-            }
-            i->getSrc(0)->reg.file = FILE_MEMORY_GLOBAL;
-            i->setIndirect(0, 1, NULL);
-            i->setIndirect(0, 0, ptr);
-            bld.mkCmp(OP_SET, CC_GT, TYPE_U32, pred, TYPE_U32, offset, length);
-            i->setPredicate(CC_NOT_P, pred);
-            if (i->defExists(0)) {
-               bld.mkMov(i->getDef(0), bld.mkImm(0));
-            }
-         } else if (fileIndex >= 0) {
-            Value *ptr = loadUboInfo64(ind, fileIndex * 16);
-            if (i->src(0).isIndirect(0)) {
-               bld.mkOp2(OP_ADD, TYPE_U64, ptr, ptr, i->getIndirect(0, 0));
-            }
-            i->getSrc(0)->reg.file = FILE_MEMORY_GLOBAL;
-            i->setIndirect(0, 1, NULL);
-            i->setIndirect(0, 0, ptr);
+         assert(fileIndex >= 0 || ind);
+
+         Value *offset = bld.loadImm(NULL, i->getSrc(0)->reg.data.offset + typeSizeof(i->sType));
+         Value *ptr = loadUboInfo64(ind, fileIndex * 16);
+         Value *length = loadUboLength32(ind, fileIndex * 16);
+         Value *pred = new_LValue(func, FILE_PREDICATE);
+         if (i->src(0).isIndirect(0)) {
+            bld.mkOp2(OP_ADD, TYPE_U64, ptr, ptr, i->getIndirect(0, 0));
+            bld.mkOp2(OP_ADD, TYPE_U32, offset, offset, i->getIndirect(0, 0));
          }
+         i->getSrc(0)->reg.file = FILE_MEMORY_GLOBAL;
+         i->setIndirect(0, 1, NULL);
+         i->setIndirect(0, 0, ptr);
+         bld.mkCmp(OP_SET, CC_GT, TYPE_U32, pred, TYPE_U32, offset, length);
+         i->setPredicate(CC_NOT_P, pred);
+         Value *zero, *dst = i->getDef(0);
+         i->setDef(0, bld.getSSA());
+
+         bld.setPosition(i, true);
+         bld.mkMov((zero = bld.getSSA()), bld.mkImm(0))
+            ->setPredicate(CC_P, pred);
+         bld.mkOp2(OP_UNION, TYPE_U32, dst, i->getDef(0), zero);
       } else if (i->src(0).isIndirect(1)) {
          Value *ptr;
          if (i->src(0).isIndirect(0))
-- 
2.10.2