x86 and ppc for 100% dense switch statements when relocations are non-PIC.
This support will be extended and enhanced in the coming days to support
PIC, and less dense forms of jump tables.
llvm-svn: 27947
manner that the LowerSwitch LLVM to LLVM pass does: emitting a binary
search tree of basic blocks. The new approach has several advantages:
it is faster, it generates significantly smaller code in many cases, and
it paves the way for implementing dense switch tables as a jump table by
handling switches directly in the instruction selector.
This functionality is currently only enabled on x86, but should be safe for
every target. In anticipation of making it the default, the cfg is now
properly updated in the x86, ppc, and sparc select lowering code.
llvm-svn: 27156
Make the PPC backend not dependent on BRTWOWAY_CC and make the branch
selector smarter about the code it generates, fixing a case in the
readme.
llvm-svn: 26814
The ABI specifies that there is a register save area at the bottom of the
stack, which means the actual used pointer needs to be an offset from
the subtracted value.
llvm-svn: 26202
