So after SIBLING_CALL_P flags gets now preserved in peep2_attempt, the patch simplifies.
Regression tested for x86_64-unknown-linux-gnu, and i686-pc-cygwin. Ok for apply (with ChangeLog plus testcase adjustment as done by initial patch)? Index: config/i386/i386.md =================================================================== --- config/i386/i386.md (Revision 211212) +++ config/i386/i386.md (Arbeitskopie) @@ -111,6 +111,7 @@ UNSPEC_LEA_ADDR UNSPEC_XBEGIN_ABORT UNSPEC_STOS + UNSPEC_PEEPSIB ;; For SSE/MMX support: UNSPEC_FIX_NOTRUNC @@ -11382,6 +11383,61 @@ "* return ix86_output_call_insn (insn, operands[0]);" [(set_attr "type" "call")]) +(define_insn "*sibcall_intern" + [(call (unspec [(mem:QI (match_operand:W 0 "memory_operand"))] UNSPEC_PEEPSIB) + (match_operand 1))] + "" + "* return ix86_output_call_insn (insn, operands[0]);" + [(set_attr "type" "call")]) + +(define_peephole2 + [(set (match_operand:DI 0 "register_operand") + (match_operand:DI 1 "memory_operand")) + (call (mem:QI (match_operand:DI 2 "register_operand")) + (match_operand 3))] + "TARGET_64BIT && REG_P (operands[0]) + && REG_P (operands[2]) + && SIBLING_CALL_P (peep2_next_insn (1)) + && REGNO (operands[0]) == REGNO (operands[2])" + [(call (unspec [(mem:QI (match_dup 1))] UNSPEC_PEEPSIB) (match_dup 3))]) + +(define_peephole2 + [(set (match_operand:DI 0 "register_operand") + (match_operand:DI 1 "memory_operand")) + (unspec_volatile [(const_int 0)] UNSPECV_BLOCKAGE) + (call (mem:QI (match_operand:DI 2 "register_operand")) + (match_operand 3))] + "TARGET_64BIT && REG_P (operands[0]) + && REG_P (operands[2]) + && SIBLING_CALL_P (peep2_next_insn (2)) + && REGNO (operands[0]) == REGNO (operands[2])" + [(unspec_volatile [(const_int 0)] UNSPECV_BLOCKAGE) + (call (unspec [(mem:QI (match_dup 1))] UNSPEC_PEEPSIB) (match_dup 3))]) + +(define_peephole2 + [(set (match_operand:SI 0 "register_operand") + (match_operand:SI 1 "memory_operand")) + (call (mem:QI (match_operand:SI 2 "register_operand")) + (match_operand 3))] + "!TARGET_64BIT && REG_P (operands[0]) + && REG_P (operands[2]) + && SIBLING_CALL_P (peep2_next_insn (1)) + && REGNO (operands[0]) == REGNO (operands[2])" + [(call (unspec [(mem:QI (match_dup 1))] UNSPEC_PEEPSIB) (match_dup 3))]) + +(define_peephole2 + [(set (match_operand:SI 0 "register_operand") + (match_operand:SI 1 "memory_operand")) + (unspec_volatile [(const_int 0)] UNSPECV_BLOCKAGE) + (call (mem:QI (match_operand:SI 2 "register_operand")) + (match_operand 3))] + "!TARGET_64BIT && REG_P (operands[0]) + && REG_P (operands[2]) + && SIBLING_CALL_P (peep2_next_insn (2)) + && REGNO (operands[0]) == REGNO (operands[2])" + [(unspec_volatile [(const_int 0)] UNSPECV_BLOCKAGE) + (call (unspec [(mem:QI (match_dup 1))] UNSPEC_PEEPSIB) (match_dup 3))]) + (define_expand "call_pop" [(parallel [(call (match_operand:QI 0) (match_operand:SI 1)) @@ -11415,6 +11471,16 @@ "* return ix86_output_call_insn (insn, operands[0]);" [(set_attr "type" "call")]) +(define_insn "*sibcall_pop_intern" + [(call (unspec [(mem:QI (match_operand:SI 0 "memory_operand"))] UNSPEC_PEEPSIB) + (match_operand 1)) + (set (reg:SI SP_REG) + (plus:SI (reg:SI SP_REG) + (match_operand:SI 2 "immediate_operand" "i")))] + "!TARGET_64BIT" + "* return ix86_output_call_insn (insn, operands[0]);" + [(set_attr "type" "call")]) + ;; Call subroutine, returning value in operand 0 (define_expand "call_value" @@ -11457,6 +11523,14 @@ "* return ix86_output_call_insn (insn, operands[1]);" [(set_attr "type" "callv")]) +(define_insn "*sibcall_value_intern" + [(set (match_operand 0) + (call (unspec [(mem:QI (match_operand:W 1 "memory_operand"))] UNSPEC_PEEPSIB) + (match_operand 2)))] + "" + "* return ix86_output_call_insn (insn, operands[1]);" + [(set_attr "type" "callv")]) + (define_insn "*call_value_rex64_ms_sysv" [(match_parallel 3 "call_rex64_ms_sysv_operation" [(set (match_operand 0) @@ -11503,6 +11577,17 @@ "* return ix86_output_call_insn (insn, operands[1]);" [(set_attr "type" "callv")]) +(define_insn "*sibcall_value_pop_intern" + [(set (match_operand 0) + (call (unspec [(mem:QI (match_operand:SI 1 "memory_operand"))] UNSPEC_PEEPSIB) + (match_operand 2))) + (set (reg:SI SP_REG) + (plus:SI (reg:SI SP_REG) + (match_operand:SI 3 "immediate_operand" "i")))] + "!TARGET_64BIT" + "* return ix86_output_call_insn (insn, operands[1]);" + [(set_attr "type" "callv")]) + ;; Call subroutine returning any type. (define_expand "untyped_call"