[Mesa-dev] [PATCH v2 1/3] ac: add 64bit bitCount support

[Timothy Arceri]

v2: use LLVMBuildTrunc()
---
 src/amd/common/ac_nir_to_llvm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index 348ac5bab4..2af4c39e28 100644
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -1917,7 +1917,12 @@ static void visit_alu(struct ac_nir_context *ctx, const nir_alu_instr *instr)
 		result = ac_build_intrinsic(&ctx->ac, "llvm.bitreverse.i32", ctx->ac.i32, src, 1, AC_FUNC_ATTR_READNONE);
 		break;
 	case nir_op_bit_count:
-		result = ac_build_intrinsic(&ctx->ac, "llvm.ctpop.i32", ctx->ac.i32, src, 1, AC_FUNC_ATTR_READNONE);
+		if (get_elem_bits(&ctx->ac, LLVMTypeOf(src[0])) == 32)
+			result = ac_build_intrinsic(&ctx->ac, "llvm.ctpop.i32", ctx->ac.i32, src, 1, AC_FUNC_ATTR_READNONE);
+		else {
+			result = ac_build_intrinsic(&ctx->ac, "llvm.ctpop.i64", ctx->ac.i64, src, 1, AC_FUNC_ATTR_READNONE);
+			result = LLVMBuildTrunc(ctx->ac.builder, result, ctx->ac.i32, "");
+		}
 		break;
 	case nir_op_vec2:
 	case nir_op_vec3:
-- 
2.14.3