Bill Schmidt 42d43351b2 This patch addresses an ABI compatibility issue with empty aggregate ... parameters. Examples of these are: struct { } a; union { } b[256]; int a[0]; An empty aggregate has an address, although dereferencing that address is pointless. When passed as a parameter, an empty aggregate does not consume a protocol register, nor does it consume a doubleword in the parameter save area. Passing an empty aggregate by reference passes an address just as for any other aggregate. Returning an empty aggregate uses GPR3 as a hidden address of the return value location, just as for any other aggregate. The patch modifies PPCTargetLowering::LowerFormalArguments_64SVR4 and PPCTargetLowering::LowerCall_64SVR4 to properly skip empty aggregate parameters passed by value. The handling of return values and by-reference parameters was already correct. Built on powerpc64-unknown-linux-gnu and tested with no new regressions. A test case is included to test proper handling of empty aggregate parameters on both sides of the function call protocol. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167090 91177308-0d34-0410-b5e6-96231b3b80d8		2012-10-31 01:15:05 +00:00
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Mips	[mips] Allow tail-call optimization for vararg functions and functions which	2012-10-30 20:16:31 +00:00
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PowerPC	This patch addresses an ABI compatibility issue with empty aggregate	2012-10-31 01:15:05 +00:00
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X86	X86 SSE: update rsqrtss and rcpss to use two source operands and	2012-10-30 23:53:59 +00:00
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