ac: add support for 16bit UBO loads

Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>

3 files changed, 51 insertions, 3 deletions

diff --git a/src/amd/common/ac_llvm_build.c b/src/amd/common/ac_llvm_build.c
index 4078b005e54..54b7e987015 100644
--- a/src/amd/common/ac_llvm_build.c
+++ b/src/amd/common/ac_llvm_build.c
@@ -1103,6 +1103,31 @@ LLVMValueRef ac_build_buffer_load_format_gfx9_safe(struct ac_llvm_context *ctx,
 	                                   can_speculate, true);
 }
 
+LLVMValueRef
+ac_build_tbuffer_load_short(struct ac_llvm_context *ctx,
+			    LLVMValueRef rsrc,
+			    LLVMValueRef vindex,
+			    LLVMValueRef voffset,
+				LLVMValueRef soffset,
+				LLVMValueRef immoffset)
+{
+	const char *name = "llvm.amdgcn.tbuffer.load.i32";
+	LLVMTypeRef type = ctx->i32;
+	LLVMValueRef params[] = {
+				rsrc,
+				vindex,
+				voffset,
+				soffset,
+				immoffset,
+				LLVMConstInt(ctx->i32, V_008F0C_BUF_DATA_FORMAT_16, false),
+				LLVMConstInt(ctx->i32, V_008F0C_BUF_NUM_FORMAT_UINT, false),
+				ctx->i1false,
+				ctx->i1false,
+	};
+	LLVMValueRef res = ac_build_intrinsic(ctx, name, type, params, 9, 0);
+	return LLVMBuildTrunc(ctx->builder, res, ctx->i16, "");
+}
+
 /**
  * Set range metadata on an instruction.  This can only be used on load and
  * call instructions.  If you know an instruction can only produce the values
diff --git a/src/amd/common/ac_llvm_build.h b/src/amd/common/ac_llvm_build.h
index 4e7cbcd5fa0..c5753037e7b 100644
--- a/src/amd/common/ac_llvm_build.h
+++ b/src/amd/common/ac_llvm_build.h
@@ -253,6 +253,14 @@ LLVMValueRef ac_build_buffer_load_format_gfx9_safe(struct ac_llvm_context *ctx,
                                                   bool can_speculate);
 
 LLVMValueRef
+ac_build_tbuffer_load_short(struct ac_llvm_context *ctx,
+			    LLVMValueRef rsrc,
+			    LLVMValueRef vindex,
+			    LLVMValueRef voffset,
+				LLVMValueRef soffset,
+				LLVMValueRef immoffset);
+
+LLVMValueRef
 ac_get_thread_id(struct ac_llvm_context *ctx);
 
 #define AC_TID_MASK_TOP_LEFT 0xfffffffc
diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
index e3b5ae49fdf..3fde6609796 100644
--- a/src/amd/common/ac_nir_to_llvm.c
+++ b/src/amd/common/ac_nir_to_llvm.c
@@ -1677,9 +1677,24 @@ static LLVMValueRef visit_load_ubo_buffer(struct ac_nir_context *ctx,
 	if (instr->dest.ssa.bit_size == 64)
 		num_components *= 2;
 
-	ret = ac_build_buffer_load(&ctx->ac, rsrc, num_components, NULL, offset,
-				   NULL, 0, false, false, true, true);
-	ret = ac_trim_vector(&ctx->ac, ret, num_components);
+	if (instr->dest.ssa.bit_size == 16) {
+		LLVMValueRef results[num_components];
+		for (unsigned i = 0; i < num_components; ++i) {
+			results[i] = ac_build_tbuffer_load_short(&ctx->ac,
+								 rsrc,
+								 ctx->ac.i32_0,
+								 offset,
+								 ctx->ac.i32_0,
+								 LLVMConstInt(ctx->ac.i32, 2 * i, 0));
+		}
+		ret = ac_build_gather_values(&ctx->ac, results, num_components);
+	} else {
+		ret = ac_build_buffer_load(&ctx->ac, rsrc, num_components, NULL, offset,
+					   NULL, 0, false, false, true, true);
+
+		ret = ac_trim_vector(&ctx->ac, ret, num_components);
+	}
+
 	return LLVMBuildBitCast(ctx->ac.builder, ret,
 	                        get_def_type(ctx, &instr->dest.ssa), "");
 }