Ulrich Weigand 7fc5011e8d [PowerPC] ELFv2 stack space reduction ... The ELFv2 ABI reduces the amount of stack required to implement an ABI-compliant function call in two ways: * the "linkage area" is reduced from 48 bytes to 32 bytes by eliminating two unused doublewords * the 64-byte "parameter save area" is now optional and need not be present in certain cases (it remains mandatory in functions with variable arguments, and functions that have any parameter that is passed on the stack) The following patch implements this required changes: - reducing the linkage area, and associated relocation of the TOC save slot, in getLinkageSize / getTOCSaveOffset (this requires updating all callers of these routines to pass in the isELFv2ABI flag). - (partially) handling the case where the parameter save are is optional This latter part requires some extra explanation: Currently, we still always allocate the parameter save area when *calling* a function. That is certainly always compliant with the ABI, but may cause code to allocate stack unnecessarily. This can be addressed by a follow-on optimization patch. On the *callee* side, in LowerFormalArguments, we *must* track correctly whether the ABI guarantees that the caller has allocated the parameter save area for our use, and the patch does so. However, there is one complication: the code that handles incoming "byval" arguments will currently *always* write to the parameter save area, because it has to force incoming register arguments to the stack since it must return an *address* to implement the byval semantics. To fix this, the patch changes the LowerFormalArguments code to write arguments to a freshly allocated stack slot on the function's own stack frame instead of the argument save area in those cases where that area is not present. Reviewed by Hal Finkel. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213490 91177308-0d34-0410-b5e6-96231b3b80d8		2014-07-20 23:43:15 +00:00
..
AArch64	AArch64: implement efficient f16 bitcasts	2014-07-18 13:07:05 +00:00
ARM	ARM: correct WoA __builtin_alloca handling on O0	2014-07-19 01:29:51 +00:00
CPP	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
Generic	Add a new attribute called 'jumptable' that creates jump-instruction tables for functions marked with this attribute.	2014-06-05 19:29:43 +00:00
Hexagon	Reduce verbiage of lit.local.cfg files	2014-06-09 22:42:55 +00:00
Inputs
Mips	[mips] For the FP64A ABI, odd-numbered double-precision moves must not use mtc1/mfc1.	2014-07-14 13:08:14 +00:00
MSP430	Reduce verbiage of lit.local.cfg files	2014-06-09 22:42:55 +00:00
NVPTX	Add tests for atomic adds on floats.	2014-07-18 20:11:26 +00:00
PowerPC	[PowerPC] ELFv2 stack space reduction	2014-07-20 23:43:15 +00:00
R600	R600: Add missing test for concat_vectors	2014-07-20 07:13:17 +00:00
SPARC	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
SystemZ	IR: add "cmpxchg weak" variant to support permitted failure.	2014-06-13 14:24:07 +00:00
Thumb	ARM: Fix fastcc calling convention for Thumb1	2014-06-13 08:33:03 +00:00
Thumb2	ARM: Fix TPsoft for Thumb mode	2014-06-24 15:45:59 +00:00
X86	[x86] Fix wrong shuffle mask in test 'combine-vec-shuffle-3.ll'. No functional change.	2014-07-19 07:52:58 +00:00
XCore	llvm/test/CodeGen/XCore/dwarf_debug.ll: Fix not to be affected by *-win32.	2014-07-04 11:58:03 +00:00