freedreno/ir3/cf: handle widening too

We can also fold f16->f32 conversions.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4423>

diff --git a/src/freedreno/ir3/ir3_cf.c b/src/freedreno/ir3/ir3_cf.c
index 2c2dc06c27a98fc45395a225d1782a85c2a0a0c0..636ed384d792eb6f6885541c8d92634940de439b 100644 (file)
--- a/src/freedreno/ir3/ir3_cf.c
+++ b/src/freedreno/ir3/ir3_cf.c
@@ -26,11 +26,26 @@
 static bool
 is_fp16_conv(struct ir3_instruction *instr)
 {
-       if (instr->opc == OPC_MOV &&
-                       instr->cat1.src_type == TYPE_F32 &&
+       if (instr->opc != OPC_MOV)
+               return false;
+
+       struct ir3_register *dst = instr->regs[0];
+       struct ir3_register *src = instr->regs[1];
+
+       /* disallow conversions that cannot be folded into
+        * alu instructions:
+        */
+       if (dst->flags & (IR3_REG_EVEN | IR3_REG_POS_INF))
+               return false;
+
+       if (instr->cat1.src_type == TYPE_F32 &&
                        instr->cat1.dst_type == TYPE_F16)
                return true;
 
+       if (instr->cat1.src_type == TYPE_F16 &&
+                       instr->cat1.dst_type == TYPE_F32)
+               return true;
+
        return false;
 }
 
@@ -77,8 +92,15 @@ try_conversion_folding(struct ir3 *ir, struct ir3_instruction *conv)
        if (!is_alu(src))
                return;
 
+       /* avoid folding f2f32(f2f16) together, in cases where this is legal to
+        * do (glsl) nir should have handled that for us already:
+        */
+       if (is_fp16_conv(src))
+               return;
+
        switch (src->opc) {
        case OPC_SEL_B32:
+       case OPC_SEL_B16:
        case OPC_MAX_F:
        case OPC_MIN_F:
        case OPC_SIGN_F:
@@ -97,18 +119,22 @@ try_conversion_folding(struct ir3 *ir, struct ir3_instruction *conv)
                         * change the dst type to F32 to get the right behavior, since we
                         * could be moving a float with a u32.u32 move.
                         */
-                       src->cat1.dst_type = TYPE_F16;
-                       src->cat1.src_type = TYPE_F32;
+                       src->cat1.dst_type = conv->cat1.dst_type;
+                       src->cat1.src_type = conv->cat1.src_type;
                } else {
                        /* Otherwise, for typechanging movs, we can just change the dst
                         * type to F16 to collaps the two conversions.  For example
                         * cov.s32f32 follwed by cov.f32f16 becomes cov.s32f16.
                         */
-                       src->cat1.dst_type = TYPE_F16;
+                       src->cat1.dst_type = conv->cat1.dst_type;
                }
        }
 
-       src->regs[0]->flags |= IR3_REG_HALF;
+       if (conv->regs[0]->flags & IR3_REG_HALF) {
+               src->regs[0]->flags |= IR3_REG_HALF;
+       } else {
+               src->regs[0]->flags &= ~IR3_REG_HALF;
+       }
 
        rewrite_uses(ir, conv, src);
 }