From: Eric Anholt <eric@anholt.net>
Date: Thu, 28 Apr 2016 01:49:59 +0000 (-0700)
Subject: vc4: Emit only one FRAG_Z or FRAG_W QIR opcode.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=b145b731ab01937993e2bf7ecc072217932568ff;p=mesa.git

vc4: Emit only one FRAG_Z or FRAG_W QIR opcode.

We were generating piles of FRAG_W for interpolation, only to CSE them
away immediately.  Since this is the only thing that CSE is doing for us
any more, just avoid making the CSE work necessary.
---

diff --git a/src/gallium/drivers/vc4/vc4_qir.h b/src/gallium/drivers/vc4/vc4_qir.h
index 789918dee68..62624d4b1e2 100644
--- a/src/gallium/drivers/vc4/vc4_qir.h
+++ b/src/gallium/drivers/vc4/vc4_qir.h
@@ -374,6 +374,8 @@ struct vc4_compile {
 
         struct qreg line_x, point_x, point_y;
         struct qreg discard;
+        struct qreg payload_FRAG_Z;
+        struct qreg payload_FRAG_W;
 
         uint8_t vattr_sizes[8];
 
@@ -584,6 +586,21 @@ qir_##name(struct vc4_compile *c, struct qreg dest, struct qreg a)       \
         return dest;                                                     \
 }
 
+#define QIR_PAYLOAD(name)                                                \
+static inline struct qreg                                                \
+qir_##name(struct vc4_compile *c)                                        \
+{                                                                        \
+        struct qreg *payload = &c->payload_##name;                       \
+        if (payload->file != QFILE_NULL)                                 \
+                return *payload;                                         \
+        *payload = qir_get_temp(c);                                      \
+        struct qinst *inst = qir_inst(QOP_##name, *payload,              \
+                                      c->undef, c->undef);               \
+        list_add(&inst->link, &c->instructions);                         \
+        c->defs[payload->index] = inst;                                  \
+        return *payload;                                                 \
+}
+
 QIR_ALU1(MOV)
 QIR_ALU1(FMOV)
 QIR_ALU1(MMOV)
@@ -625,8 +642,8 @@ QIR_NODST_2(TEX_T)
 QIR_NODST_2(TEX_R)
 QIR_NODST_2(TEX_B)
 QIR_NODST_2(TEX_DIRECT)
-QIR_ALU0(FRAG_Z)
-QIR_ALU0(FRAG_W)
+QIR_PAYLOAD(FRAG_Z)
+QIR_PAYLOAD(FRAG_W)
 QIR_ALU0(TEX_RESULT)
 QIR_ALU0(TLB_COLOR_READ)
 QIR_NODST_1(MS_MASK)