Date: Wed, 20 Nov 2013 18:03:32 +1030
From: Alan Modra <amodra at gmail dot com>
To: libffi-discuss at sourceware dot org
Subject: PowerPC64 ELFv2 fix 1 of 2
Message-ID: <20131120073332.GF22514@bubble.grove.modra.org>
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Using the return value area as a place to pass parameters wasn't such
a good idea, causing a failure of cls_ulonglong.c.  I didn't see this
when running the mainline gcc libffi testsuite because that version of
the test is inferior to the upstreamm libffi test.

	* src/powerpc/linux64_closure.S: Don't use the return value area
	as a parameter save area on ELFv2.

diff --git a/src/powerpc/linux64_closure.S b/src/powerpc/linux64_closure.S
index 9b6b5f3..4d012cc 100644
--- a/src/powerpc/linux64_closure.S
+++ b/src/powerpc/linux64_closure.S
@@ -60,13 +60,11 @@ ffi_closure_LINUX64:
 # endif
 
 # if _CALL_ELF == 2
-#  32 byte special reg save area + 64 byte parm save area and retval
-#  + 13*8 fpr save area + round to 16
-#  define STACKFRAME 208
+#  32 byte special reg save area + 64 byte parm save area
+#  + 64 byte retval area + 13*8 fpr save area + round to 16
+#  define STACKFRAME 272
 #  define PARMSAVE 32
-#  No parameter save area is needed for the call to ffi_closure_helper_LINUX64,
-#  so return value can start there.
-#  define RETVAL PARMSAVE
+#  define RETVAL PARMSAVE+64
 # else
 #  48 bytes special reg save area + 64 bytes parm save area
 #  + 16 bytes retval area + 13*8 bytes fpr save area + round to 16
@@ -85,8 +83,8 @@ ffi_closure_LINUX64:
 	bt	7, .Lparmsave
 	# Our caller has not allocated a parameter save area.
 	# We need to allocate one here and use it to pass gprs to
-	# ffi_closure_helper_LINUX64.  The return value area will do.
-	addi	%r12, %r1, -STACKFRAME+RETVAL
+	# ffi_closure_helper_LINUX64.
+	addi	%r12, %r1, -STACKFRAME+PARMSAVE
 .Lparmsave:
 	std	%r0, 16(%r1)
 	# Save general regs into parm save area

-- 
Alan Modra
Australia Development Lab, IBM