In certain circumstances, findFirstUses could end up doubling back on instructions it had already processed, resulting in an infinite recursion. Avoid this by keeping track of already-visited instructions.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=83079 Tested-by: Tobias Klausmann <tobias.johannes.klausm...@mni.thm.de> Signed-off-by: Ilia Mirkin <imir...@alum.mit.edu> Cc: "10.2 10.3" <mesa-sta...@lists.freedesktop.org> --- .../nouveau/codegen/nv50_ir_lowering_nvc0.cpp | 32 +++++++++++++++++----- .../nouveau/codegen/nv50_ir_lowering_nvc0.h | 5 +++- 2 files changed, 29 insertions(+), 8 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 7da9b0b..92f9a15 100644 --- a/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.cpp +++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.cpp @@ -174,15 +174,31 @@ NVC0LegalizePostRA::findOverwritingDefs(const Instruction *texi, } void -NVC0LegalizePostRA::findFirstUses(const Instruction *texi, - const Instruction *insn, - std::list<TexUse> &uses) +NVC0LegalizePostRA::findFirstUses( + const Instruction *texi, + const Instruction *insn, + std::list<TexUse> &uses, + std::tr1::unordered_set<const Instruction *>& visited) { for (int d = 0; insn->defExists(d); ++d) { Value *v = insn->getDef(d); for (Value::UseIterator u = v->uses.begin(); u != v->uses.end(); ++u) { Instruction *usei = (*u)->getInsn(); + /* XXX HACK ALERT XXX + * + * This shouldn't have to be here, we should always be making forward + * progress by looking at the uses. However this somehow does not + * appear to be the case. Probably because this is being done right + * after RA, when the defs/uses lists have been messed with by node + * merging. This should probably be moved to being done right before + * RA. But this will do for now. + */ + if (visited.find(usei) != visited.end()) + continue; + + visited.insert(usei); + if (usei->op == OP_PHI || usei->op == OP_UNION) { // need a barrier before WAW cases for (int s = 0; usei->srcExists(s); ++s) { @@ -197,11 +213,11 @@ NVC0LegalizePostRA::findFirstUses(const Instruction *texi, usei->op == OP_PHI || usei->op == OP_UNION) { // these uses don't manifest in the machine code - findFirstUses(texi, usei, uses); + findFirstUses(texi, usei, uses, visited); } else if (usei->op == OP_MOV && usei->getDef(0)->equals(usei->getSrc(0)) && usei->subOp != NV50_IR_SUBOP_MOV_FINAL) { - findFirstUses(texi, usei, uses); + findFirstUses(texi, usei, uses, visited); } else { addTexUse(uses, usei, insn); } @@ -257,8 +273,10 @@ NVC0LegalizePostRA::insertTextureBarriers(Function *fn) uses = new std::list<TexUse>[texes.size()]; if (!uses) return false; - for (size_t i = 0; i < texes.size(); ++i) - findFirstUses(texes[i], texes[i], uses[i]); + for (size_t i = 0; i < texes.size(); ++i) { + std::tr1::unordered_set<const Instruction *> visited; + findFirstUses(texes[i], texes[i], uses[i], visited); + } // determine the barrier level at each use for (size_t i = 0; i < texes.size(); ++i) { diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.h b/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.h index 7f39c28..d8ff5cd 100644 --- a/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.h +++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_lowering_nvc0.h @@ -20,6 +20,8 @@ * OTHER DEALINGS IN THE SOFTWARE. */ +#include <tr1/unordered_set> + #include "codegen/nv50_ir.h" #include "codegen/nv50_ir_build_util.h" @@ -69,7 +71,8 @@ private: bool insertTextureBarriers(Function *); inline bool insnDominatedBy(const Instruction *, const Instruction *) const; void findFirstUses(const Instruction *tex, const Instruction *def, - std::list<TexUse>&); + std::list<TexUse>&, + std::tr1::unordered_set<const Instruction *>&); void findOverwritingDefs(const Instruction *tex, Instruction *insn, const BasicBlock *term, std::list<TexUse>&); -- 1.8.5.5 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
