Mesa (master): llvmpipe: Fix deferred depth writes for Z16_UNORM.

[Jose Fonseca]

Module: Mesa
Branch: master
Commit: 3b683700efe81f82ba2f978d6c645385e5ccfa97
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=3b683700efe81f82ba2f978d6c645385e5ccfa97

Author: José Fonseca <jfonseca at vmware.com>
Date:   Tue Jan 29 10:45:01 2013 +0000

llvmpipe: Fix deferred depth writes for Z16_UNORM.

This special path hadn't been exercised by my earlier testing, and mask
values weren't being properly truncated to match the values.

This change fixes that.

Reviewed-by: Brian Paul <brianp at vmware.com>
Reviewed-by: Roland Scheidegger <sroland at vmware.com>

---

 src/gallium/drivers/llvmpipe/lp_bld_depth.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/src/gallium/drivers/llvmpipe/lp_bld_depth.c b/src/gallium/drivers/llvmpipe/lp_bld_depth.c
index 1c899b3..24c997d 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_depth.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_depth.c
@@ -893,6 +893,7 @@ lp_build_deferred_depth_write(struct gallivm_state *gallivm,
    struct lp_build_context z_bld;
    LLVMValueRef z_dst;
    LLVMBuilderRef builder = gallivm->builder;
+   LLVMValueRef mask_value;
 
    /* XXX: pointlessly redo type logic:
     */
@@ -904,11 +905,15 @@ lp_build_deferred_depth_write(struct gallivm_state *gallivm,
 
    z_dst = LLVMBuildLoad(builder, zs_dst_ptr, "zsbufval");
 
+   mask_value = lp_build_mask_value(mask);
+
    if (z_type.width < z_src_type.width) {
+      /* Truncate incoming ZS and mask values (e.g., when writing to Z16_UNORM) */
       zs_value = LLVMBuildTrunc(builder, zs_value, z_bld.vec_type, "");
+      mask_value = LLVMBuildTrunc(builder, mask_value, z_bld.int_vec_type, "");
    }
 
-   z_dst = lp_build_select(&z_bld, lp_build_mask_value(mask), zs_value, z_dst);
+   z_dst = lp_build_select(&z_bld, mask_value, zs_value, z_dst);
 
    LLVMBuildStore(builder, z_dst, zs_dst_ptr);
 }