nvc0: recognize r63 as zero in constant folding

3 files changed, 9 insertions, 13 deletions

diff --git a/src/gallium/drivers/nvc0/nvc0_pc.c b/src/gallium/drivers/nvc0/nvc0_pc.c
index 304a1919768..1d1b9e19b78 100644
--- a/src/gallium/drivers/nvc0/nvc0_pc.c
+++ b/src/gallium/drivers/nvc0/nvc0_pc.c
@@ -103,6 +103,12 @@ nvc0_pc_replace_value(struct nv_pc *pc,
    return n;
 }
 
+static INLINE boolean
+is_gpr63(struct nv_value *val)
+{
+   return (val->reg.file == NV_FILE_GPR && val->reg.id == 63);
+}
+
 struct nv_value *
 nvc0_pc_find_constant(struct nv_ref *ref)
 {
@@ -116,7 +122,7 @@ nvc0_pc_find_constant(struct nv_ref *ref)
       assert(!src->insn->src[0]->mod);
       src = src->insn->src[0]->value;
    }
-   if ((src->reg.file == NV_FILE_IMM) ||
+   if ((src->reg.file == NV_FILE_IMM) || is_gpr63(src) ||
        (src->insn &&
         src->insn->opcode == NV_OP_LD &&
         src->insn->src[0]->value->reg.file >= NV_FILE_MEM_C(0) &&
@@ -130,7 +136,7 @@ nvc0_pc_find_immediate(struct nv_ref *ref)
 {
    struct nv_value *src = nvc0_pc_find_constant(ref);
 
-   return (src && src->reg.file == NV_FILE_IMM) ? src : NULL;
+   return (src && (src->reg.file == NV_FILE_IMM || is_gpr63(src))) ? src : NULL;
 }
 
 static void
diff --git a/src/gallium/drivers/nvc0/nvc0_pc.h b/src/gallium/drivers/nvc0/nvc0_pc.h
index 969cc68c596..01ca95b0741 100644
--- a/src/gallium/drivers/nvc0/nvc0_pc.h
+++ b/src/gallium/drivers/nvc0/nvc0_pc.h
@@ -310,7 +310,7 @@ struct nv_reg {
       int32_t s32;
       int64_t s64;
       uint64_t u64;
-      uint32_t u32;
+      uint32_t u32; /* expected to be 0 for $r63 */
       float f32;
       double f64;
    } imm;
diff --git a/src/gallium/drivers/nvc0/nvc0_tgsi_to_nc.c b/src/gallium/drivers/nvc0/nvc0_tgsi_to_nc.c
index 950bee2eda4..3709369ca2f 100644
--- a/src/gallium/drivers/nvc0/nvc0_tgsi_to_nc.c
+++ b/src/gallium/drivers/nvc0/nvc0_tgsi_to_nc.c
@@ -1388,16 +1388,6 @@ emit_tex(struct bld_context *bld, uint opcode, int tic, int tsc,
    return nvi;
 }
 
-/*
-static boolean
-bld_is_constant(struct nv_value *val)
-{
-   if (val->reg.file == NV_FILE_IMM)
-      return TRUE;
-   return val->insn && nvCG_find_constant(val->insn->src[0]);
-}
-*/
-
 static void
 bld_tex(struct bld_context *bld, struct nv_value *dst0[4],
         const struct tgsi_full_instruction *insn)