vc4: Avoid emitting small immediates for UBO indirect load address guards.

The kernel will reject our shader if we emit one here, and having 4, 8, or
12 as the top end of our UBO clamp rare is enough that it's not worth
making the kernel let us.

Fixes piglit fs-const-array-of-struct and
fs-const-array-of-struct-of-array since recent GLSL linking changes made
us get this as an indirect load of a uniform, instead of a tempoary.

Cc: "13.0 17.0" <mesa-stable@lists.freedesktop.org>

diff --git a/src/gallium/drivers/vc4/vc4_opt_small_immediates.c b/src/gallium/drivers/vc4/vc4_opt_small_immediates.c
index 89c4857..07eca71 100644 (file)
--- a/src/gallium/drivers/vc4/vc4_opt_small_immediates.c
+++ b/src/gallium/drivers/vc4/vc4_opt_small_immediates.c
@@ -52,6 +52,17 @@ qir_opt_small_immediates(struct vc4_compile *c)
                 if (uses_small_imm)
                         continue;
 
+                /* Don't propagate small immediates into the top-end bounds
+                 * checking for indirect UBO loads.  The kernel doesn't parse
+                 * small immediates and rejects the shader in this case.  UBO
+                 * loads are much more expensive than the uniform load, and
+                 * indirect UBO regions are usually much larger than a small
+                 * immediate, so it's not worth updating the kernel to allow
+                 * optimizing it.
+                 */
+                if (inst->op == QOP_MIN_NOIMM)
+                        continue;
+
                 for (int i = 0; i < qir_get_nsrc(inst); i++) {
                         struct qreg src = qir_follow_movs(c, inst->src[i]);
 

diff --git a/src/gallium/drivers/vc4/vc4_program.c b/src/gallium/drivers/vc4/vc4_program.c
index a7cc668..4865bcb 100644 (file)
--- a/src/gallium/drivers/vc4/vc4_program.c
+++ b/src/gallium/drivers/vc4/vc4_program.c
@@ -116,9 +116,9 @@ indirect_uniform_load(struct vc4_compile *c, nir_intrinsic_instr *intr)
 
         /* Clamp to [0, array size).  Note that MIN/MAX are signed. */
         indirect_offset = qir_MAX(c, indirect_offset, qir_uniform_ui(c, 0));
-        indirect_offset = qir_MIN(c, indirect_offset,
-                                  qir_uniform_ui(c, (range->dst_offset +
-                                                     range->size - 4)));
+        indirect_offset = qir_MIN_NOIMM(c, indirect_offset,
+                                        qir_uniform_ui(c, (range->dst_offset +
+                                                           range->size - 4)));
 
         qir_ADD_dest(c, qir_reg(QFILE_TEX_S_DIRECT, 0),
                      indirect_offset,
@@ -382,7 +382,7 @@ ntq_emit_txf(struct vc4_compile *c, nir_tex_instr *instr)
 
         /* Perform the clamping required by kernel validation. */
         addr = qir_MAX(c, addr, qir_uniform_ui(c, 0));
-        addr = qir_MIN(c, addr,  qir_uniform_ui(c, size - 4));
+        addr = qir_MIN_NOIMM(c, addr, qir_uniform_ui(c, size - 4));
 
         qir_ADD_dest(c, qir_reg(QFILE_TEX_S_DIRECT, 0),
                      addr, qir_uniform(c, QUNIFORM_TEXTURE_MSAA_ADDR, unit));

diff --git a/src/gallium/drivers/vc4/vc4_qir.c b/src/gallium/drivers/vc4/vc4_qir.c
index d4f35d8..ed76c64 100644 (file)
--- a/src/gallium/drivers/vc4/vc4_qir.c
+++ b/src/gallium/drivers/vc4/vc4_qir.c
@@ -58,6 +58,7 @@ static const struct qir_op_info qir_op_info[] = {
         [QOP_ASR] = { "asr", 1, 2 },
         [QOP_SHL] = { "shl", 1, 2 },
         [QOP_MIN] = { "min", 1, 2 },
+        [QOP_MIN_NOIMM] = { "min_noimm", 1, 2 },
         [QOP_MAX] = { "max", 1, 2 },
         [QOP_AND] = { "and", 1, 2 },
         [QOP_OR] = { "or", 1, 2 },

diff --git a/src/gallium/drivers/vc4/vc4_qir.h b/src/gallium/drivers/vc4/vc4_qir.h
index e189bc3..daeb52b 100644 (file)
--- a/src/gallium/drivers/vc4/vc4_qir.h
+++ b/src/gallium/drivers/vc4/vc4_qir.h
@@ -123,6 +123,7 @@ enum qop {
         QOP_SHR,
         QOP_ASR,
         QOP_MIN,
+        QOP_MIN_NOIMM,
         QOP_MAX,
         QOP_AND,
         QOP_OR,
@@ -725,6 +726,7 @@ QIR_ALU2(SHL)
 QIR_ALU2(SHR)
 QIR_ALU2(ASR)
 QIR_ALU2(MIN)
+QIR_ALU2(MIN_NOIMM)
 QIR_ALU2(MAX)
 QIR_ALU2(AND)
 QIR_ALU2(OR)

diff --git a/src/gallium/drivers/vc4/vc4_qpu_emit.c b/src/gallium/drivers/vc4/vc4_qpu_emit.c
index 47fc0b0..60ca87a 100644 (file)
--- a/src/gallium/drivers/vc4/vc4_qpu_emit.c
+++ b/src/gallium/drivers/vc4/vc4_qpu_emit.c
@@ -285,6 +285,8 @@ vc4_generate_code_block(struct vc4_compile *c,
                         [QOP_MOV] = { QPU_A_OR },
                         [QOP_FMOV] = { QPU_A_FMAX },
                         [QOP_MMOV] = { QPU_M_V8MIN },
+
+                        [QOP_MIN_NOIMM] = { QPU_A_MIN },
                 };
 
                 uint64_t unpack = 0;