vc4: Add support for loading immediate values in QIR.

This will be used for resetting the uniform stream in the presence of
branching, but may also be useful as an optimization to reduce how many
uniforms we have to copy out per draw call (in exchange for increasing
icache pressure).

1 files changed, 17 insertions, 0 deletions

diff --git a/src/gallium/drivers/vc4/vc4_qir.h b/src/gallium/drivers/vc4/vc4_qir.h
index d1263b64362..f541c754c88 100644
--- a/src/gallium/drivers/vc4/vc4_qir.h
+++ b/src/gallium/drivers/vc4/vc4_qir.h
@@ -62,6 +62,12 @@ enum qfile {
         QFILE_FRAG_REV_FLAG,
 
         /**
+         * Stores an immediate value in the index field that will be used
+         * directly by qpu_load_imm().
+         */
+        QFILE_LOAD_IMM,
+
+        /**
          * Stores an immediate value in the index field that can be turned
          * into a small immediate field by qpu_encode_small_immediate().
          */
@@ -147,6 +153,8 @@ enum qop {
          * the destination
          */
         QOP_TEX_RESULT,
+
+        QOP_LOAD_IMM,
 };
 
 struct queued_qpu_inst {
@@ -721,4 +729,13 @@ qir_VPM_WRITE(struct vc4_compile *c, struct qreg val)
         qir_MOV_dest(c, qir_reg(QFILE_VPM, 0), val);
 }
 
+static inline struct qreg
+qir_LOAD_IMM(struct vc4_compile *c, uint32_t val)
+{
+        struct qreg t = qir_get_temp(c);
+        qir_emit(c, qir_inst(QOP_LOAD_IMM, t,
+                             qir_reg(QFILE_LOAD_IMM, val), c->undef));
+        return t;
+}
+
 #endif /* VC4_QIR_H */