diff options
Diffstat (limited to 'gcc/config/i386/i386.md')
| -rw-r--r-- | gcc/config/i386/i386.md | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md index ec43793..4ccd932 100644 --- a/gcc/config/i386/i386.md +++ b/gcc/config/i386/i386.md @@ -104,6 +104,7 @@ UNSPEC_LD_MPIC ; load_macho_picbase UNSPEC_TRUNC_NOOP UNSPEC_DIV_ALREADY_SPLIT + UNSPEC_NOPS ;; For SSE/MMX support: UNSPEC_FIX_NOTRUNC @@ -11465,6 +11466,39 @@ (set_attr "length_immediate" "0") (set_attr "modrm" "0")]) +;; Generate nops. Operand 0 is the number of nops, up to 8. +(define_insn "nops" + [(unspec [(match_operand 0 "const_int_operand" "")] + UNSPEC_NOPS)] + "reload_completed" +{ + switch (INTVAL (operands[0])) + { + case 1: + return "nop"; + case 2: + return "nop; nop"; + case 3: + return "nop; nop; nop"; + case 4: + return "nop; nop; nop; nop"; + case 5: + return "nop; nop; nop; nop; nop"; + case 6: + return "nop; nop; nop; nop; nop; nop"; + case 7: + return "nop; nop; nop; nop; nop; nop; nop"; + case 8: + return "nop; nop; nop; nop; nop; nop; nop; nop"; + default: + gcc_unreachable (); + break; + } +} + [(set (attr "length") (symbol_ref "INTVAL (operands[0])")) + (set_attr "length_immediate" "0") + (set_attr "modrm" "0")]) + ;; Pad to 16-byte boundary, max skip in op0. Used to avoid ;; branch prediction penalty for the third jump in a 16-byte ;; block on K8. |