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authorHal Finkel <hfinkel@anl.gov>2015-01-05 21:41:26 +0000
committerHal Finkel <hfinkel@anl.gov>2015-01-05 21:41:26 +0000
commit92a87c67eeac09cbc8ad7ad69a9fe1be99d570b7 (patch)
tree1ea8af79c8c2412af52e10d15704efbde408980e
parente4f1dcdb83f0fa3a32613c009f13da2aff55456d (diff)
[PowerPC] Remove README.txt entry
This entry has been rendered irrelevant now that we have proper CR bit tracking. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225211 91177308-0d34-0410-b5e6-96231b3b80d8
-rw-r--r--lib/Target/PowerPC/README.txt34
1 files changed, 0 insertions, 34 deletions
diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index 9565ae131f8..29238fd2a55 100644
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -184,40 +184,6 @@ just fastcc.
===-------------------------------------------------------------------------===
-Compile this:
-
-int foo(int a) {
- int b = (a < 8);
- if (b) {
- return b * 3; // ignore the fact that this is always 3.
- } else {
- return 2;
- }
-}
-
-into something not this:
-
-_foo:
-1) cmpwi cr7, r3, 8
- mfcr r2, 1
- rlwinm r2, r2, 29, 31, 31
-1) cmpwi cr0, r3, 7
- bgt cr0, LBB1_2 ; UnifiedReturnBlock
-LBB1_1: ; then
- rlwinm r2, r2, 0, 31, 31
- mulli r3, r2, 3
- blr
-LBB1_2: ; UnifiedReturnBlock
- li r3, 2
- blr
-
-In particular, the two compares (marked 1) could be shared by reversing one.
-This could be done in the dag combiner, by swapping a BR_CC when a SETCC of the
-same operands (but backwards) exists. In this case, this wouldn't save us
-anything though, because the compares still wouldn't be shared.
-
-===-------------------------------------------------------------------------===
-
Fold add and sub with constant into non-extern, non-weak addresses so this:
static int a;