i965/vs: Respect the gen6 limitation that math opcodes can't be align16.

Fixes vs-acos-vec3 and friends.

2 files changed, 33 insertions, 2 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
index 21830f99fc2..effc82a8004 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_emit.cpp
@@ -250,6 +250,14 @@ vec4_visitor::generate_math1_gen6(vec4_instruction *inst,
 				  struct brw_reg dst,
 				  struct brw_reg src)
 {
+   /* Can't do writemask because math can't be align16. */
+   assert(dst.dw1.bits.writemask == WRITEMASK_XYZW);
+   /* Source swizzles are ignored. */
+   assert(!src.abs);
+   assert(!src.negate);
+   assert(src.dw1.bits.swizzle = BRW_SWIZZLE_XYZW);
+
+   brw_set_access_mode(p, BRW_ALIGN_1);
    brw_math(p,
 	    dst,
 	    brw_math_function(inst->opcode),
@@ -258,6 +266,7 @@ vec4_visitor::generate_math1_gen6(vec4_instruction *inst,
 	    src,
 	    BRW_MATH_DATA_SCALAR,
 	    BRW_MATH_PRECISION_FULL);
+   brw_set_access_mode(p, BRW_ALIGN_16);
 }
 
 void
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index fde1d67759a..f4756a9a1a8 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -129,7 +129,18 @@ vec4_visitor::emit_math1_gen6(enum opcode opcode, dst_reg dst, src_reg src)
    src_reg temp_src = src_reg(this, glsl_type::vec4_type);
    emit(BRW_OPCODE_MOV, dst_reg(temp_src), src);
 
-   emit(opcode, dst, temp_src);
+   if (dst.writemask != WRITEMASK_XYZW) {
+      /* The gen6 math instruction must be align1, so we can't do
+       * writemasks.
+       */
+      dst_reg temp_dst = dst_reg(this, glsl_type::vec4_type);
+
+      emit(opcode, temp_dst, temp_src);
+
+      emit(BRW_OPCODE_MOV, dst, src_reg(temp_dst));
+   } else {
+      emit(opcode, dst, temp_src);
+   }
 }
 
 void
@@ -184,7 +195,18 @@ vec4_visitor::emit_math2_gen6(enum opcode opcode,
    emit(BRW_OPCODE_MOV, dst, src1);
    src1 = expanded;
 
-   emit(opcode, dst, src0, src1);
+   if (dst.writemask != WRITEMASK_XYZW) {
+      /* The gen6 math instruction must be align1, so we can't do
+       * writemasks.
+       */
+      dst_reg temp_dst = dst_reg(this, glsl_type::vec4_type);
+
+      emit(opcode, temp_dst, src0, src1);
+
+      emit(BRW_OPCODE_MOV, dst, src_reg(temp_dst));
+   } else {
+      emit(opcode, dst, src0, src1);
+   }
 }
 
 void