Mercurial > pub > dyncall > dyncall
diff doc/disas_examples/ppc64.elfabi.disas @ 497:cb19b2fe2422
- more disas examples to check behaviour of passing C++ non-trivial aggregates by value; they all behave the same, calling the copy ctor first, passing a pointer then
| author | Tassilo Philipp |
|---|---|
| date | Wed, 23 Mar 2022 15:24:31 +0100 |
| parents | ead041d93e36 |
| children | fc614cb865c6 |
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--- a/doc/disas_examples/ppc64.elfabi.disas Mon Mar 21 18:11:38 2022 +0100 +++ b/doc/disas_examples/ppc64.elfabi.disas Wed Mar 23 15:24:31 2022 +0100 @@ -734,5 +734,101 @@ +; ---------- C++ trivial and non-trivial aggrs passed to C funcs ----------> +; +; struct Trivial { int a; }; +; struct NonTrivial { int a; NonTrivial() : a(0) {} NonTrivial(const NonTrivial& rhs) : a(rhs.a) { } }; +; +; extern "C" { +; +; void f1(struct Trivial s) { } +; void f2(struct NonTrivial s) { } +; +; void f() +; { +; struct Trivial t; +; struct NonTrivial n; +; int a=1; +; a += 123; +; f1(t); +; a -= 123; +; f2(n); +; a -= 12; +; } +; } + + + +; output from freebsd-11.0-ppc64 w/ gcc 4.2.1 + +0000000010000828 <.f1>: + 10000828: fb e1 ff f8 std r31,-8(r1) + 1000082c: f8 21 ff c1 stdu r1,-64(r1) + 10000830: 7c 3f 0b 78 mr r31,r1 + 10000834: 90 7f 00 70 stw r3,112(r31) + 10000838: e8 21 00 00 ld r1,0(r1) + 1000083c: eb e1 ff f8 ld r31,-8(r1) + 10000840: 4e 80 00 20 blr + 10000844: 00 00 00 00 .long 0x0 + 10000848: 00 09 00 00 .long 0x90000 + 1000084c: 80 01 00 01 lwz r0,1(r1) + +0000000010000850 <.f2>: + 10000850: fb e1 ff f8 std r31,-8(r1) + 10000854: f8 21 ff c1 stdu r1,-64(r1) + 10000858: 7c 3f 0b 78 mr r31,r1 + 1000085c: f8 7f 00 70 std r3,112(r31) + 10000860: e8 21 00 00 ld r1,0(r1) + 10000864: eb e1 ff f8 ld r31,-8(r1) + 10000868: 4e 80 00 20 blr + 1000086c: 00 00 00 00 .long 0x0 + 10000870: 00 09 00 00 .long 0x90000 + 10000874: 80 01 00 01 lwz r0,1(r1) + +0000000010000878 <.f>: + 10000878: 7c 08 02 a6 mflr r0 ; + 1000087c: fb e1 ff f8 std r31,-8(r1) ; + 10000880: f8 01 00 10 std r0,16(r1) ; + 10000884: f8 21 ff 71 stdu r1,-144(r1) ; + 10000888: 7c 3f 0b 78 mr r31,r1 ; + 1000088c: 38 1f 00 7c addi r0,r31,124 ; + 10000890: 7c 03 03 78 mr r3,r0 ; + 10000894: 48 00 00 ad bl 10000940 <._ZN10NonTrivialC1Ev> ; NonTrivial::NonTrivial() / ctor + 10000898: 4f ff fb 82 crmove 4*cr7+so,4*cr7+so ; + 1000089c: 38 00 00 01 li r0,1 ; + 100008a0: 90 1f 00 70 stw r0,112(r31) ; + 100008a4: 81 3f 00 70 lwz r9,112(r31) ; + 100008a8: 38 09 00 7b addi r0,r9,123 ; + 100008ac: 90 1f 00 70 stw r0,112(r31) ; + 100008b0: 80 7f 00 78 lwz r3,120(r31) ; + 100008b4: 4b ff ff 75 bl 10000828 <.f1> ; call f1(struct Trivial) + 100008b8: 81 3f 00 70 lwz r9,112(r31) ; + 100008bc: 38 09 ff 85 addi r0,r9,-123 ; + 100008c0: 90 1f 00 70 stw r0,112(r31) ; + 100008c4: 38 1f 00 74 addi r0,r31,116 ; + 100008c8: 39 3f 00 7c addi r9,r31,124 ; + 100008cc: 7c 03 03 78 mr r3,r0 ; | ptr to dest of copy of n + 100008d0: 7d 24 4b 78 mr r4,r9 ; | copy n ptr to n + 100008d4: 48 00 00 a1 bl 10000974 <._ZN10NonTrivialC1ERKS_> ; | NonTrivial::NonTrivial(const NonTrivial&) / copy ctor + 100008d8: 4f ff fb 82 crmove 4*cr7+so,4*cr7+so ; + 100008dc: 38 1f 00 74 addi r0,r31,116 ; | + 100008e0: 7c 03 03 78 mr r3,r0 ; | f2 arg 0 (ptr to copy of struct NonTrivial), via ptr as non-trivial + 100008e4: 4b ff ff 6d bl 10000850 <.f2> ; call f2(struct NonTrivial) + 100008e8: 81 3f 00 70 lwz r9,112(r31) ; + 100008ec: 38 09 ff f4 addi r0,r9,-12 ; + 100008f0: 90 1f 00 70 stw r0,112(r31) ; + 100008f4: e8 21 00 00 ld r1,0(r1) ; + 100008f8: e8 01 00 10 ld r0,16(r1) ; + 100008fc: 7c 08 03 a6 mtlr r0 ; + 10000900: eb e1 ff f8 ld r31,-8(r1) ; + 10000904: 4e 80 00 20 blr ; + 10000908: 00 00 00 00 .long 0x0 ; + 1000090c: 00 09 00 01 .long 0x90001 ; + 10000910: 80 01 00 01 lwz r0,1(r1) ; + + ; ... snip, removed code of ctor and copy ctor ... + + + ; vim: ft=asm