Hi, I modified prior patch so that it uses the new predicate sibcall_memory_operand to extend sibcall_insn_operand. Just one change in i386.c remains about x86_output_mi_thunk. Later one isn't pretty much essential. Nevertheless it makes code equivalent to none-memory-case for potential tail-sibcalls.
ChangeLog gcc 2014-05-28 Kai Tietz <kti...@redhat.com> * config/i386/i386.c (x86_output_mi_thunk): Add memory case for sibling-tail-calls. * config/i386/i386.md (sibcall_insn_operand): Add memory-constrain to its use. * config/i386/predicates.md (sibcall_memory_operand): New predicate. (sibcall_insn_operand): Add check for sibcall_memory_operand. ChangeLog testsuite 2014-05-28 Kai Tietz <kti...@redhat.com> PR target/60104 * gcc.target/i386/sibcall-1.c: New test. * gcc.target/i386/sibcall-2.c: New test. * gcc.target/i386/sibcall-3.c: New test. Regression tested x86_64-unknown-linux-gnu multilib, x86_64-w64-mingw32, and i686-pc-cygwin. Ok for apply? Regards, Kai Index: gcc/config/i386/i386.c =================================================================== --- gcc/config/i386/i386.c (revision 210985) +++ gcc/config/i386/i386.c (working copy) @@ -38893,7 +38893,16 @@ x86_output_mi_thunk (FILE *file, For our purposes here, we can get away with (ab)using a jump pattern, because we're going to do no optimization. */ if (MEM_P (fnaddr)) - emit_jump_insn (gen_indirect_jump (fnaddr)); + { + if (sibcall_insn_operand (fnaddr, word_mode)) + { + tmp = gen_rtx_CALL (VOIDmode, fnaddr, const0_rtx); + tmp = emit_call_insn (tmp); + SIBLING_CALL_P (tmp) = 1; + } + else + emit_jump_insn (gen_indirect_jump (fnaddr)); + } else { if (ix86_cmodel == CM_LARGE_PIC && SYMBOLIC_CONST (fnaddr)) Index: gcc/config/i386/i386.md =================================================================== --- gcc/config/i386/i386.md (revision 210985) +++ gcc/config/i386/i386.md (working copy) @@ -11376,7 +11376,7 @@ [(set_attr "type" "call")]) (define_insn "*sibcall" - [(call (mem:QI (match_operand:W 0 "sibcall_insn_operand" "Uz")) + [(call (mem:QI (match_operand:W 0 "sibcall_insn_operand" "Uzm")) (match_operand 1))] "SIBLING_CALL_P (insn)" "* return ix86_output_call_insn (insn, operands[0]);" @@ -11406,7 +11406,7 @@ [(set_attr "type" "call")]) (define_insn "*sibcall_pop" - [(call (mem:QI (match_operand:SI 0 "sibcall_insn_operand" "Uz")) + [(call (mem:QI (match_operand:SI 0 "sibcall_insn_operand" "Uzm")) (match_operand 1)) (set (reg:SI SP_REG) (plus:SI (reg:SI SP_REG) @@ -11451,7 +11451,7 @@ (define_insn "*sibcall_value" [(set (match_operand 0) - (call (mem:QI (match_operand:W 1 "sibcall_insn_operand" "Uz")) + (call (mem:QI (match_operand:W 1 "sibcall_insn_operand" "Uzm")) (match_operand 2)))] "SIBLING_CALL_P (insn)" "* return ix86_output_call_insn (insn, operands[1]);" @@ -11494,7 +11494,7 @@ (define_insn "*sibcall_value_pop" [(set (match_operand 0) - (call (mem:QI (match_operand:SI 1 "sibcall_insn_operand" "Uz")) + (call (mem:QI (match_operand:SI 1 "sibcall_insn_operand" "Uzm")) (match_operand 2))) (set (reg:SI SP_REG) (plus:SI (reg:SI SP_REG) Index: gcc/config/i386/predicates.md =================================================================== --- gcc/config/i386/predicates.md (revision 210985) +++ gcc/config/i386/predicates.md (working copy) @@ -71,6 +71,16 @@ return ANY_QI_REG_P (op); }) +(define_predicate "sibcall_memory_operand" + (match_operand 0 "memory_operand") +{ + op = XEXP (op, 0); + + if (GET_CODE (op) == CONST) + op = XEXP (op, 0); + return (GET_CODE (op) == SYMBOL_REF || CONSTANT_P (op)); +}) + ;; Match an SI or HImode register for a zero_extract. (define_special_predicate "ext_register_operand" (match_operand 0 "register_operand") @@ -600,7 +610,9 @@ (define_special_predicate "sibcall_insn_operand" (ior (match_test "constant_call_address_operand (op, mode == VOIDmode ? mode : Pmode)") - (match_operand 0 "register_no_elim_operand"))) + (match_operand 0 "register_no_elim_operand") + (and (not (match_test "TARGET_X32")) + (match_operand 0 "sibcall_memory_operand")))) ;; Return true if OP is a call from MS ABI to SYSV ABI function. (define_predicate "call_rex64_ms_sysv_operation" Index: gcc/testsuite/gcc.target/i386/sibcall-1.c =================================================================== --- gcc/testsuite/gcc.target/i386/sibcall-1.c (revision 0) +++ gcc/testsuite/gcc.target/i386/sibcall-1.c (working copy) @@ -0,0 +1,12 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target ia32 } */ +/* { dg-options "-O2" } */ + +extern int (*foo)(int); + +int boo (int a) +{ + return (*foo) (a); +} + +/* { dg-final { scan-assembler-not "mov" } } */ Index: gcc/testsuite/gcc.target/i386/sibcall-2.c =================================================================== --- gcc/testsuite/gcc.target/i386/sibcall-2.c (revision 0) +++ gcc/testsuite/gcc.target/i386/sibcall-2.c (working copy) @@ -0,0 +1,16 @@ +/* { dg-do compile { xfail { *-*-* } } } */ +/* { dg-require-effective-target ia32 } */ +/* { dg-options "-O2" } */ + +extern int doo1 (int); +extern int doo2 (int); +extern void bar (char *); + +int foo (int a) +{ + char s[256]; + bar (s); + return (a < 0 ? doo1 : doo2) (a); +} + +/* { dg-final { scan-assembler-not "call[ \t]*.%eax" } } */ Index: gcc/testsuite/gcc.target/i386/sibcall-3.c =================================================================== --- gcc/testsuite/gcc.target/i386/sibcall-3.c (revision 0) +++ gcc/testsuite/gcc.target/i386/sibcall-3.c (working copy) @@ -0,0 +1,16 @@ +/* { dg-do compile } */ +/* { dg-require-effective-target ia32 } */ +/* { dg-options "-O2" } */ + +extern +#ifdef _WIN32 + __declspec (dllimport) +#endif + void foo (int a); + +void bar (int a) +{ + return foo (a); +} + +/* { dg-final { scan-assembler-not "jmp[ \t]*.%eax" } } */ Index: gcc/testsuite/gcc.target/i386/sibcall-4.c =================================================================== --- gcc/testsuite/gcc.target/i386/sibcall-4.c (revision 0) +++ gcc/testsuite/gcc.target/i386/sibcall-4.c (working copy) @@ -0,0 +1,15 @@ +/* Testcase for PR target/46219. */ +/* { dg-do compile { xfail { *-*-* } } */ +/* { dg-require-effective-target ia32 } */ +/* { dg-options "-O2" } */ + +typedef void (*dispatch_t)(long offset); + +dispatch_t dispatch[256]; + +void male_indirect_jump (long offset) +{ + dispatch[offset](offset); +} + +/* { dg-final { scan-assembler-not "jmp[ \t]*.%eax" } } */