From bb9e962490e093cb33e4cda2e8c6716d843100bd Mon Sep 17 00:00:00 2001
From: Jonas Maebe <jonas@freepascal.org>
Date: Fri, 2 Jan 2009 15:36:27 +0000
Subject: [PATCH] * fixed procvar parameter passing on ppc/sysv (by value
instead of by reference -- except for method procvars, for tmethod record
compatibility) * adapted tw11563 for corrected calling convention
git-svn-id: trunk@12475 -
---
compiler/powerpc/cpupara.pas | 25 +++++++++++++++++++++++--
tests/webtbs/tw11563.pp | 7 ++++++-
2 files changed, 29 insertions(+), 3 deletions(-)
diff --git a/compiler/powerpc/cpupara.pas b/compiler/powerpc/cpupara.pas
index 03a00a2b71..d1124cd26c 100644
--- a/compiler/powerpc/cpupara.pas
+++ b/compiler/powerpc/cpupara.pas
@@ -130,7 +130,12 @@ unit cpupara;
result:=LOC_REGISTER;
classrefdef:
result:=LOC_REGISTER;
- procvardef,
+ procvardef:
+ if (target_info.abi = abi_powerpc_aix) or
+ (p.size = sizeof(pint)) then
+ result:=LOC_REGISTER
+ else
+ result:=LOC_REFERENCE;
recorddef:
if (target_info.abi<>abi_powerpc_aix) or
((p.size >= 3) and
@@ -181,8 +186,24 @@ unit cpupara;
variantdef,
formaldef :
result:=true;
- recorddef,
+ { regular procvars must be passed by value, because you cannot pass
+ the address of a local stack location when calling e.g.
+ pthread_create with the address of a function (first of all it
+ expects the address of the function to execute and not the address
+ of a memory location containing that address, and secondly if you
+ first store the address on the stack and then pass the address of
+ this stack location, then this stack location may no longer be
+ valid when the newly started thread accesses it.
+
+ However, for "procedure of object" we must use the same calling
+ convention as for "8 byte record" due to the need for
+ interchangeability with the TMethod record type.
+ }
procvardef :
+ result:=
+ (target_info.abi <> abi_powerpc_aix) and
+ (def.size <> sizeof(pint));
+ recorddef :
result :=
(target_info.abi<>abi_powerpc_aix) or
((varspez = vs_const) and
diff --git a/tests/webtbs/tw11563.pp b/tests/webtbs/tw11563.pp
index 010349aa36..94caf6572a 100644
--- a/tests/webtbs/tw11563.pp
+++ b/tests/webtbs/tw11563.pp
@@ -19,15 +19,20 @@ program ExecStack;
begin
{$if defined(cpupowerpc) or defined(cpupowerpc64)}
+ ret := ($4e shl 24) or ($80 shl 16) or ($00 shl 8) or $20;
+{$if defined(cpupowerpc64)}
{ can't use proc(@ret) because linux/ppc64 always expects some kind of
trampoline
}
- ret := ($4e shl 24) or ($80 shl 16) or ($00 shl 8) or $20;
asm
la r0, ret
mtctr r0
bctrl
end;
+{$else}
+ DoNothing := proc(@ret);
+ DoNothing;
+{$endif}
{$endif}
{$if defined(cpui386) or defined(cpux86_64)}
ret := $C3;