Index: config/i386/i386.c =================================================================== --- config/i386/i386.c (revision 246473) +++ config/i386/i386.c (working copy) @@ -37572,9 +37572,6 @@ ix86_expand_builtin (tree exp, rtx target, rtx sub mode0 = DImode; rdrand_step: - op0 = gen_reg_rtx (mode0); - emit_insn (GEN_FCN (icode) (op0)); - arg0 = CALL_EXPR_ARG (exp, 0); op1 = expand_normal (arg0); if (!address_operand (op1, VOIDmode)) @@ -37582,6 +37579,10 @@ rdrand_step: op1 = convert_memory_address (Pmode, op1); op1 = copy_addr_to_reg (op1); } + + op0 = gen_reg_rtx (mode0); + emit_insn (GEN_FCN (icode) (op0)); + emit_move_insn (gen_rtx_MEM (mode0, op1), op0); op1 = gen_reg_rtx (SImode); @@ -37590,8 +37591,20 @@ rdrand_step: /* Emit SImode conditional move. */ if (mode0 == HImode) { - op2 = gen_reg_rtx (SImode); - emit_insn (gen_zero_extendhisi2 (op2, op0)); + if (TARGET_ZERO_EXTEND_WITH_AND + && optimize_function_for_speed_p (cfun)) + { + op2 = force_reg (SImode, const0_rtx); + + emit_insn (gen_movstricthi + (gen_lowpart (HImode, op2), op0)); + } + else + { + op2 = gen_reg_rtx (SImode); + + emit_insn (gen_zero_extendhisi2 (op2, op0)); + } } else if (mode0 == SImode) op2 = op0; @@ -37623,9 +37636,6 @@ rdrand_step: mode0 = DImode; rdseed_step: - op0 = gen_reg_rtx (mode0); - emit_insn (GEN_FCN (icode) (op0)); - arg0 = CALL_EXPR_ARG (exp, 0); op1 = expand_normal (arg0); if (!address_operand (op1, VOIDmode)) @@ -37633,6 +37643,10 @@ rdseed_step: op1 = convert_memory_address (Pmode, op1); op1 = copy_addr_to_reg (op1); } + + op0 = gen_reg_rtx (mode0); + emit_insn (GEN_FCN (icode) (op0)); + emit_move_insn (gen_rtx_MEM (mode0, op1), op0); op2 = gen_reg_rtx (QImode);