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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22732 91177308-0d34-0410-b5e6-96231b3b80d8
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Chris Lattner 2005-08-09 22:30:57 +00:00
parent 079a27a0de
commit c7e18a10d4
1 changed files with 18 additions and 0 deletions
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18
lib/Target/PowerPC/README.txt
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@ -11,6 +11,24 @@ TODO:
* Support 'update' load/store instructions. These are cracked on the G5, but
are still a codesize win.
* Add a custom legalizer for the GlobalAddress node, to move the funky darwin
stub stuff from the instruction selector to the legalizer (exposing low-level
operations to the dag for optzn. For example, we want to codegen this:
int A = 0;
void B() { A++; }
as:
lis r9,ha16(_A)
lwz r2,lo16(_A)(r9)
addi r2,r2,1
stw r2,lo16(_A)(r9)
not:
lis r2, ha16(_A)
lwz r2, lo16(_A)(r2)
addi r2, r2, 1
lis r3, ha16(_A)
stw r2, lo16(_A)(r3)
* should hint to the branch select pass that it doesn't need to print the
second unconditional branch, so we don't end up with things like:
b .LBBl42__2E_expand_function_8_674 ; loopentry.24