i965: Use greater-equal cmod to implement maximum.

The docs specifically call out SEL with .l and .ge as the
implementations of MIN and MAX respectively. Among other things, SEL
with these conditional mods are commutative.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>

diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index 74860711abd96d844080bbb730688f60e4965d87..4b48f2db0f212cde016b7da665ef132b3aa4da98 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -321,6 +321,9 @@ void
 fs_visitor::emit_minmax(enum brw_conditional_mod conditionalmod, const fs_reg &dst,
                         const fs_reg &src0, const fs_reg &src1)
 {
+   assert(conditionalmod == BRW_CONDITIONAL_GE ||
+          conditionalmod == BRW_CONDITIONAL_L);
+
    fs_inst *inst;
 
    if (brw->gen >= 6) {
@@ -1956,7 +1959,7 @@ fs_visitor::rescale_texcoord(fs_reg coordinate, int coord_components,
            chan = offset(chan, i);
 
            inst = emit(BRW_OPCODE_SEL, chan, chan, fs_reg(0.0f));
-           inst->conditional_mod = BRW_CONDITIONAL_G;
+           inst->conditional_mod = BRW_CONDITIONAL_GE;
 
            /* Our parameter comes in as 1.0/width or 1.0/height,
             * because that's what people normally want for doing

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index 6154e43c1a4deabcb073625610074b8c900a8874..be071d74baa2ed1a0db28e3357e804ab57b4f6a0 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -517,7 +517,7 @@ vec4_visitor::emit_unpack_snorm_4x8(const dst_reg &dst, src_reg src0)
    emit(MUL(scaled, src_reg(f), src_reg(1.0f / 127.0f)));
 
    dst_reg max(this, glsl_type::vec4_type);
-   emit_minmax(BRW_CONDITIONAL_G, max, src_reg(scaled), src_reg(-1.0f));
+   emit_minmax(BRW_CONDITIONAL_GE, max, src_reg(scaled), src_reg(-1.0f));
    emit_minmax(BRW_CONDITIONAL_L, dst, src_reg(max), src_reg(1.0f));
 }
 
@@ -545,7 +545,7 @@ void
 vec4_visitor::emit_pack_snorm_4x8(const dst_reg &dst, const src_reg &src0)
 {
    dst_reg max(this, glsl_type::vec4_type);
-   emit_minmax(BRW_CONDITIONAL_G, max, src0, src_reg(-1.0f));
+   emit_minmax(BRW_CONDITIONAL_GE, max, src0, src_reg(-1.0f));
 
    dst_reg min(this, glsl_type::vec4_type);
    emit_minmax(BRW_CONDITIONAL_L, min, src_reg(max), src_reg(1.0f));
@@ -1683,7 +1683,7 @@ vec4_visitor::visit(ir_expression *ir)
       emit_minmax(BRW_CONDITIONAL_L, result_dst, op[0], op[1]);
       break;
    case ir_binop_max:
-      emit_minmax(BRW_CONDITIONAL_G, result_dst, op[0], op[1]);
+      emit_minmax(BRW_CONDITIONAL_GE, result_dst, op[0], op[1]);
       break;
 
    case ir_binop_pow:

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp b/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp
index a5a5e7bfd5bfa357f913d36bfa28e989b57d10b4..ba3264dce6fa29b357e867678ef752ed609672ce 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_vp.cpp
@@ -226,7 +226,7 @@ vec4_vs_visitor::emit_program_code()
                /* if (tmp.y < 0) tmp.y = 0; */
                src_reg tmp_y = swizzle(src[0], BRW_SWIZZLE_YYYY);
                result.writemask = WRITEMASK_Z;
-               emit_minmax(BRW_CONDITIONAL_G, result, tmp_y, src_reg(0.0f));
+               emit_minmax(BRW_CONDITIONAL_GE, result, tmp_y, src_reg(0.0f));
 
                src_reg clamped_y(result);
                clamped_y.swizzle = BRW_SWIZZLE_ZZZZ;
@@ -313,7 +313,7 @@ vec4_vs_visitor::emit_program_code()
       }
 
       case OPCODE_MAX:
-         emit_minmax(BRW_CONDITIONAL_G, dst, src[0], src[1]);
+         emit_minmax(BRW_CONDITIONAL_GE, dst, src[0], src[1]);
          break;
 
       case OPCODE_MIN:

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp
index 129c2db638bf535bc0d0af21c2b9c5701f53fdd7..4baf73ebde17e6eb373a3d377a8b422c31200607 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_vs_visitor.cpp
@@ -97,7 +97,7 @@ vec4_vs_visitor::emit_prolog()
                dst.type = brw_type_for_base_type(glsl_type::vec4_type);
                emit(MOV(dst, src_reg(reg_d)));
                emit(MUL(dst, src_reg(dst), src_reg(es3_normalize_factor)));
-               emit_minmax(BRW_CONDITIONAL_G, dst, src_reg(dst), src_reg(-1.0f));
+               emit_minmax(BRW_CONDITIONAL_GE, dst, src_reg(dst), src_reg(-1.0f));
             } else {
                /* The following equations are from the OpenGL 3.2 specification:
                 *