gallivm: fix lp_build_sample_offset() crash when indexing a 1-D texture

If y==NULL and y_stride==NULL it means the texture is 1D.  Return
zero for out_i and the offset instead of garbage.

diff --git a/src/gallium/auxiliary/gallivm/lp_bld_sample.c b/src/gallium/auxiliary/gallivm/lp_bld_sample.c
index 0fd014a..655c4fb 100644 (file)
--- a/src/gallium/auxiliary/gallivm/lp_bld_sample.c
+++ b/src/gallium/auxiliary/gallivm/lp_bld_sample.c
@@ -179,6 +179,9 @@ lp_build_sample_offset(struct lp_build_context *bld,
       LLVMValueRef y_offset = lp_build_mul(bld, y, y_stride);
       offset = lp_build_add(bld, offset, y_offset);
    }
+   else {
+      *out_j = bld->zero;
+   }
 
    if (z && z_stride) {
       LLVMValueRef z_offset = lp_build_mul(bld, z, z_stride);