r300/compiler: implement the Abs source operand modifier for vertex shaders

diff --git a/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c b/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c
index 276f4cb6b677c6f38a5e2362d45f6390b35d52f9..d5b08dd95926b23a015ada8836e41714c259b5a2 100644 (file)
--- a/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c
+++ b/src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c
@@ -146,7 +146,8 @@ static unsigned long t_src(struct r300_vertex_program_code *vp,
                               t_swizzle(GET_SWZ(src->Swizzle, 2)),
                               t_swizzle(GET_SWZ(src->Swizzle, 3)),
                               t_src_class(src->File),
-                              src->Negate) | (src->RelAddr << 4);
+                              src->Negate) |
+              (src->RelAddr << 4) | (src->Abs << 3);
 }
 
 static unsigned long t_src_scalar(struct r300_vertex_program_code *vp,
@@ -162,7 +163,7 @@ static unsigned long t_src_scalar(struct r300_vertex_program_code *vp,
                               t_swizzle(GET_SWZ(src->Swizzle, 0)),
                               t_src_class(src->File),
                               src->Negate ? RC_MASK_XYZW : RC_MASK_NONE) |
-           (src->RelAddr << 4);
+              (src->RelAddr << 4) | (src->Abs << 3);
 }
 
 static int valid_dst(struct r300_vertex_program_code *vp,
@@ -487,6 +488,44 @@ static void allocate_temporary_registers(struct r300_vertex_program_compiler * c
        }
 }
 
+/**
+ * R3xx-R4xx vertex engine does not support the Absolute source operand modifier
+ * and the Saturate opcode modifier. Only Absolute is currently transformed.
+ */
+static int transform_nonnative_modifiers(
+       struct radeon_compiler *c,
+       struct rc_instruction *inst,
+       void* unused)
+{
+       const struct rc_opcode_info *opcode = rc_get_opcode_info(inst->U.I.Opcode);
+       unsigned i;
+
+       /* Transform ABS(a) to MAX(a, -a). */
+       for (i = 0; i < opcode->NumSrcRegs; i++) {
+               if (inst->U.I.SrcReg[i].Abs) {
+                       struct rc_instruction *new_inst;
+                       unsigned temp;
+
+                       inst->U.I.SrcReg[i].Abs = 0;
+
+                       temp = rc_find_free_temporary(c);
+
+                       new_inst = rc_insert_new_instruction(c, inst->Prev);
+                       new_inst->U.I.Opcode = RC_OPCODE_MAX;
+                       new_inst->U.I.DstReg.File = RC_FILE_TEMPORARY;
+                       new_inst->U.I.DstReg.Index = temp;
+                       new_inst->U.I.SrcReg[0] = inst->U.I.SrcReg[i];
+                       new_inst->U.I.SrcReg[1] = inst->U.I.SrcReg[i];
+                       new_inst->U.I.SrcReg[1].Negate ^= RC_MASK_XYZW;
+
+                       inst->U.I.SrcReg[i].File = RC_FILE_TEMPORARY;
+                       inst->U.I.SrcReg[i].Index = temp;
+                       inst->U.I.SrcReg[i].Negate = 0;
+                       inst->U.I.SrcReg[i].RelAddr = 0;
+               }
+       }
+       return 1;
+}
 
 /**
  * Vertex engine cannot read two inputs or two constants at the same time.
@@ -625,15 +664,27 @@ void r3xx_compile_vertex_program(struct r300_vertex_program_compiler* compiler)
                        { &r300_transform_trig_scale_vertex, 0 }
                };
                radeonLocalTransform(&compiler->Base, 2, transformations);
+
+               debug_program_log(compiler, "after native rewrite");
        } else {
                struct radeon_program_transformation transformations[] = {
                        { &r300_transform_vertex_alu, 0 },
                        { &radeonTransformTrigSimple, 0 }
                };
                radeonLocalTransform(&compiler->Base, 2, transformations);
-       }
 
-       debug_program_log(compiler, "after native rewrite");
+               debug_program_log(compiler, "after native rewrite");
+
+               /* Note: This pass has to be done seperately from ALU rewrite,
+                * because it needs to check every instruction.
+                */
+               struct radeon_program_transformation transformations2[] = {
+                       { &transform_nonnative_modifiers, 0 },
+               };
+               radeonLocalTransform(&compiler->Base, 1, transformations2);
+
+               debug_program_log(compiler, "after emulate modifiers");
+       }
 
        {
                /* Note: This pass has to be done seperately from ALU rewrite,