r600g/sb: fix issue with DCE between GVN and GCM (v2)

We can't perform DCE using the liveness pass between GVN and GCM
because it relies on the correct schedule, but GVN doesn't care about
preserving correctness - it's rescheduled later by GCM.

This patch makes dce_cleanup pass perform simple DCE
between GVN and GCM instead of relying on liveness pass.

Fixes https://bugs.freedesktop.org/show_bug.cgi?id=70088

Signed-off-by: Vadim Girlin <vadimgirlin@gmail.com>

diff --git a/src/gallium/drivers/r600/sb/sb_core.cpp b/src/gallium/drivers/r600/sb/sb_core.cpp
index b5dd88ed96d19a1a812d42f0170296489140ddd6..9fd9d9ad25a2ec5e1312f00484f56d7900435be3 100644 (file)
--- a/src/gallium/drivers/r600/sb/sb_core.cpp
+++ b/src/gallium/drivers/r600/sb/sb_core.cpp
@@ -184,6 +184,8 @@ int r600_sb_bytecode_process(struct r600_context *rctx,
                SB_RUN_PASS(psi_ops,            1);
 
        SB_RUN_PASS(liveness,                   0);
+
+       sh->dce_flags = DF_REMOVE_DEAD | DF_EXPAND;
        SB_RUN_PASS(dce_cleanup,                0);
        SB_RUN_PASS(def_use,                    0);
 
@@ -201,9 +203,10 @@ int r600_sb_bytecode_process(struct r600_context *rctx,
 
        SB_RUN_PASS(gvn,                                1);
 
-       SB_RUN_PASS(liveness,                   0);
+       SB_RUN_PASS(def_use,                    1);
+
+       sh->dce_flags = DF_REMOVE_DEAD | DF_REMOVE_UNUSED;
        SB_RUN_PASS(dce_cleanup,                1);
-       SB_RUN_PASS(def_use,                    0);
 
        SB_RUN_PASS(ra_split,                   0);
        SB_RUN_PASS(def_use,                    0);
@@ -217,6 +220,9 @@ int r600_sb_bytecode_process(struct r600_context *rctx,
        sh->compute_interferences = true;
        SB_RUN_PASS(liveness,                   0);
 
+       sh->dce_flags = DF_REMOVE_DEAD;
+       SB_RUN_PASS(dce_cleanup,                1);
+
        SB_RUN_PASS(ra_coalesce,                1);
        SB_RUN_PASS(ra_init,                    1);
 

diff --git a/src/gallium/drivers/r600/sb/sb_dce_cleanup.cpp b/src/gallium/drivers/r600/sb/sb_dce_cleanup.cpp
index f879395f67c8327ddeddcaadcc92500ca03449e4..79aef9106a4f543bbcc553e19dc59e3eb68056cb 100644 (file)
--- a/src/gallium/drivers/r600/sb/sb_dce_cleanup.cpp
+++ b/src/gallium/drivers/r600/sb/sb_dce_cleanup.cpp
@@ -56,7 +56,8 @@ bool dce_cleanup::visit(cf_node& n, bool enter) {
                else
                        cleanup_dst(n);
        } else {
-               if (n.bc.op_ptr->flags & (CF_CLAUSE | CF_BRANCH | CF_LOOP))
+               if ((sh.dce_flags & DF_EXPAND) &&
+                               (n.bc.op_ptr->flags & (CF_CLAUSE | CF_BRANCH | CF_LOOP)))
                        n.expand();
        }
        return true;
@@ -107,19 +108,20 @@ bool dce_cleanup::visit(region_node& n, bool enter) {
 }
 
 void dce_cleanup::cleanup_dst(node& n) {
-       cleanup_dst_vec(n.dst);
+       if (!cleanup_dst_vec(n.dst) && remove_unused &&
+                       !n.dst.empty() && !(n.flags & NF_DONT_KILL) && n.parent)
+               n.remove();
 }
 
 bool dce_cleanup::visit(container_node& n, bool enter) {
-       if (enter) {
+       if (enter)
                cleanup_dst(n);
-       } else {
-
-       }
        return true;
 }
 
-void dce_cleanup::cleanup_dst_vec(vvec& vv) {
+bool dce_cleanup::cleanup_dst_vec(vvec& vv) {
+       bool alive = false;
+
        for (vvec::iterator I = vv.begin(), E = vv.end(); I != E; ++I) {
                value* &v = *I;
                if (!v)
@@ -128,9 +130,13 @@ void dce_cleanup::cleanup_dst_vec(vvec& vv) {
                if (v->gvn_source && v->gvn_source->is_dead())
                        v->gvn_source = NULL;
 
-               if (v->is_dead())
+               if (v->is_dead() || (remove_unused && !v->is_rel() && !v->uses))
                        v = NULL;
+               else
+                       alive = true;
        }
+
+       return alive;
 }
 
 } // namespace r600_sb

diff --git a/src/gallium/drivers/r600/sb/sb_pass.h b/src/gallium/drivers/r600/sb/sb_pass.h
index 95d2a203a601c2b08baa40f96db2159edab5d984..a3f8515acdeae0ac02a6284bdf26d036920e587b 100644 (file)
--- a/src/gallium/drivers/r600/sb/sb_pass.h
+++ b/src/gallium/drivers/r600/sb/sb_pass.h
@@ -119,9 +119,12 @@ public:
 class dce_cleanup : public vpass {
        using vpass::visit;
 
+       bool remove_unused;
+
 public:
 
-       dce_cleanup(shader &s) : vpass(s) {}
+       dce_cleanup(shader &s) : vpass(s),
+               remove_unused(s.dce_flags & DF_REMOVE_UNUSED) {}
 
        virtual bool visit(node &n, bool enter);
        virtual bool visit(alu_group_node &n, bool enter);
@@ -135,7 +138,7 @@ public:
 private:
 
        void cleanup_dst(node &n);
-       void cleanup_dst_vec(vvec &vv);
+       bool cleanup_dst_vec(vvec &vv);
 
 };
 

diff --git a/src/gallium/drivers/r600/sb/sb_shader.h b/src/gallium/drivers/r600/sb/sb_shader.h
index e515d312d804e01fef380bcc06c55080e5c2bdbc..7955bba9b677c0ffdf3e01f9ac9c65fd346c1486 100644 (file)
--- a/src/gallium/drivers/r600/sb/sb_shader.h
+++ b/src/gallium/drivers/r600/sb/sb_shader.h
@@ -71,6 +71,16 @@ enum chunk_flags {
        RCF_PREALLOC = (1 << 4)
 };
 
+enum dce_flags {
+       DF_REMOVE_DEAD  = (1 << 0),
+       DF_REMOVE_UNUSED = (1 << 1),
+       DF_EXPAND = (1 << 2),
+};
+
+inline dce_flags operator |(dce_flags l, dce_flags r) {
+       return (dce_flags)((unsigned)l|(unsigned)r);
+}
+
 inline chunk_flags operator |(chunk_flags l, chunk_flags r) {
        return (chunk_flags)((unsigned)l|(unsigned)r);
 }
@@ -297,6 +307,8 @@ public:
 
        unsigned ngpr, nstack;
 
+       unsigned dce_flags;
+
        shader(sb_context &sctx, shader_target t, unsigned id);
 
        ~shader();