Fix flags hazard in ADC, SBC, RSC

3 files changed, 14 insertions, 1 deletions

diff --git a/rtl/core/decode/data.sv b/rtl/core/decode/data.sv
index 1bd7ef9..f744972 100644
--- a/rtl/core/decode/data.sv
+++ b/rtl/core/decode/data.sv
@@ -9,6 +9,7 @@ module core_decode_data
 	output logic       snd_is_imm,
 	                   snd_shift_by_reg_if_reg,
 	                   writeback,
+	                   conditional,
 	                   update_flags,
 	                   restore_spsr
 );
@@ -31,6 +32,14 @@ module core_decode_data
 
 	always_comb begin
 		unique case(op)
+			`ALU_ADC, `ALU_SBC, `ALU_RSC:
+				conditional = 1;
+
+			default:
+				conditional = 0;
+		endcase
+
+		unique case(op)
 			`ALU_CMP, `ALU_CMN, `ALU_TST, `ALU_TEQ:
 				writeback = 0;
 
diff --git a/rtl/core/decode/decode.sv b/rtl/core/decode/decode.sv
index f8042a9..3096c7a 100644
--- a/rtl/core/decode/decode.sv
+++ b/rtl/core/decode/decode.sv
@@ -75,12 +75,13 @@ module core_decode
 
 	data_decode data;
 	logic data_writeback, data_update_flags, data_restore_spsr,
-	      data_is_imm, data_shift_by_reg_if_reg;
+	      data_is_imm, data_shift_by_reg_if_reg, data_conditional;
 
 	core_decode_data group_data
 	(
 		.decode(data),
 		.writeback(data_writeback),
+		.conditional(data_conditional),
 		.update_flags(data_update_flags),
 		.restore_spsr(data_restore_spsr),
 		.snd_is_imm(data_is_imm),
diff --git a/rtl/core/decode/mux.sv b/rtl/core/decode/mux.sv
index 9d86f9e..65af9c6 100644
--- a/rtl/core/decode/mux.sv
+++ b/rtl/core/decode/mux.sv
@@ -16,6 +16,7 @@ module core_decode_mux
 
 	input  data_decode   data,
 	input  logic         data_writeback,
+	                     data_conditional,
 	                     data_update_flags,
 	                     data_restore_spsr,
 	                     data_is_imm,
@@ -137,7 +138,9 @@ module core_decode_mux
 				writeback = data_writeback;
 				update_flags = data_update_flags;
 				restore_spsr = data_restore_spsr;
+
 				undefined = undefined | snd_undefined;
+				conditional = conditional | data_conditional;
 			end
 
 			`GROUP_LDST_SINGLE_IMM, `GROUP_LDST_SINGLE_REG: begin