summaryrefslogtreecommitdiff
path: root/src/gallium/auxiliary/gallivm/lp_bld_logic.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/gallium/auxiliary/gallivm/lp_bld_logic.c')
-rw-r--r--src/gallium/auxiliary/gallivm/lp_bld_logic.c67
1 files changed, 45 insertions, 22 deletions
diff --git a/src/gallium/auxiliary/gallivm/lp_bld_logic.c b/src/gallium/auxiliary/gallivm/lp_bld_logic.c
index 39854e43b1..ab4ddb81c4 100644
--- a/src/gallium/auxiliary/gallivm/lp_bld_logic.c
+++ b/src/gallium/auxiliary/gallivm/lp_bld_logic.c
@@ -363,9 +363,52 @@ lp_build_cmp(struct lp_build_context *bld,
/**
+ * Return (mask & a) | (~mask & b);
+ */
+LLVMValueRef
+lp_build_select_bitwise(struct lp_build_context *bld,
+ LLVMValueRef mask,
+ LLVMValueRef a,
+ LLVMValueRef b)
+{
+ struct lp_type type = bld->type;
+ LLVMValueRef res;
+
+ if (a == b) {
+ return a;
+ }
+
+ if(type.floating) {
+ LLVMTypeRef int_vec_type = lp_build_int_vec_type(type);
+ a = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
+ b = LLVMBuildBitCast(bld->builder, b, int_vec_type, "");
+ }
+
+ a = LLVMBuildAnd(bld->builder, a, mask, "");
+
+ /* This often gets translated to PANDN, but sometimes the NOT is
+ * pre-computed and stored in another constant. The best strategy depends
+ * on available registers, so it is not a big deal -- hopefully LLVM does
+ * the right decision attending the rest of the program.
+ */
+ b = LLVMBuildAnd(bld->builder, b, LLVMBuildNot(bld->builder, mask, ""), "");
+
+ res = LLVMBuildOr(bld->builder, a, b, "");
+
+ if(type.floating) {
+ LLVMTypeRef vec_type = lp_build_vec_type(type);
+ res = LLVMBuildBitCast(bld->builder, res, vec_type, "");
+ }
+
+ return res;
+}
+
+
+/**
* Return mask ? a : b;
*
- * mask is a bitwise mask, composed of 0 or ~0 for each element.
+ * mask is a bitwise mask, composed of 0 or ~0 for each element. Any other value
+ * will yield unpredictable results.
*/
LLVMValueRef
lp_build_select(struct lp_build_context *bld,
@@ -424,27 +467,7 @@ lp_build_select(struct lp_build_context *bld,
}
}
else {
- if(type.floating) {
- LLVMTypeRef int_vec_type = lp_build_int_vec_type(type);
- a = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
- b = LLVMBuildBitCast(bld->builder, b, int_vec_type, "");
- }
-
- a = LLVMBuildAnd(bld->builder, a, mask, "");
-
- /* This often gets translated to PANDN, but sometimes the NOT is
- * pre-computed and stored in another constant. The best strategy depends
- * on available registers, so it is not a big deal -- hopefully LLVM does
- * the right decision attending the rest of the program.
- */
- b = LLVMBuildAnd(bld->builder, b, LLVMBuildNot(bld->builder, mask, ""), "");
-
- res = LLVMBuildOr(bld->builder, a, b, "");
-
- if(type.floating) {
- LLVMTypeRef vec_type = lp_build_vec_type(type);
- res = LLVMBuildBitCast(bld->builder, res, vec_type, "");
- }
+ res = lp_build_select_bitwise(bld, mask, a, b);
}
return res;