[Mesa-dev] [PATCH 3/3] nv50/ir: fix combineLd/St to update existing records as necessary

[Ilia Mirkin]

Previously the logic would decide that the record is kept, which
translates into keep = false in the caller, which meant that these
passes did not run.

While it's right that keep = false which means that a new record does
not need to be added, we do still have to perform the usual list
maintenance. It's easiest to do this pre-merge rather than post.

The lowering that clip/cull distance passes produce triggers this bug in
TCS (since reading outputs is done differently in other stages), but it
should be possible to achieve it with the right sequence of regular
reads/writes.

Fixes: KHR-GL45.cull_distance.functional
Fixes: generated_tests/spec/arb_tessellation_shader/execution/tes-input/tes-input-gl_ClipDistance.shader_test
Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Cc: mesa-stable at lists.freedesktop.org
---
 src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
index 169436a4e39..57cb7ce214d 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_peephole.cpp
@@ -2485,6 +2485,10 @@ MemoryOpt::combineLd(Record *rec, Instruction *ld)
 
    assert(sizeRc + sizeLd <= 16 && offRc != offLd);
 
+   // lock any stores that overlap with the load being merged into the
+   // existing record.
+   lockStores(ld);
+
    for (j = 0; sizeRc; sizeRc -= rec->insn->getDef(j)->reg.size, ++j);
 
    if (offLd < offRc) {
@@ -2541,6 +2545,10 @@ MemoryOpt::combineSt(Record *rec, Instruction *st)
    if (prog->getType() == Program::TYPE_COMPUTE && rec->rel[0])
       return false;
 
+   // remove any existing load/store records for the store being merged into
+   // the existing record.
+   purgeRecords(st, DATA_FILE_COUNT);
+
    st->takeExtraSources(0, extra); // save predicate and indirect address
 
    if (offRc < offSt) {
-- 
2.13.0