Dan Gohman be7227005f Implement x86 h-register extract support. ... - Add patterns for h-register extract, which avoids a shift and mask, and in some cases a temporary register. - Add address-mode matching for turning (X>>(8-n))&(255<<n), where n is a valid address-mode scale value, into an h-register extract and a scaled-offset address. - Replace X86's MOV32to32_ and related instructions with the new target-independent COPY_TO_SUBREG instruction. On x86-64 there are complicated constraints on h registers, and CodeGen doesn't currently provide a high-level way to express all of them, so they are handled with a bunch of special code. This code currently only supports extracts where the result is used by a zero-extend or a store, though these are fairly common. These transformations are not always beneficial; since there are only 4 h registers, they sometimes require extra move instructions, and this sometimes increases register pressure because it can force out values that would otherwise be in one of those registers. However, this appears to be relatively uncommon. llvm-svn: 68962		2009-04-13 16:09:41 +00:00
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Alpha
ARM	move a target-specific test into its directory so it isn't run if you	2009-04-10 23:58:38 +00:00
CBackend
CellSPU	Revert 67132. This is breaking some objective-c apps.	2009-03-25 20:20:11 +00:00
CPP
Generic	Add a new "available_externally" linkage type. This is intended	2009-04-13 05:44:34 +00:00
IA64
Mips
PowerPC	Fix this test so that it doesn't spuriously fail due to some	2009-03-27 16:17:22 +00:00
SPARC
X86	Implement x86 h-register extract support.	2009-04-13 16:09:41 +00:00
XCore