Changes in directory llvm/lib/Target/X86:
README.txt updated: 1.45 -> 1.46
---
Log message:
remove some target-indep and implemented notes
---
Diffs of the changes: (+0 -44)
README.txt | 44 --------------------------------------------
1 files changed, 44 deletions(-)
Index: llvm/lib/Target/X86/README.txt
diff -u llvm/lib/Target/X86/README.txt:1.45 llvm/lib/Target/X86/README.txt:1.46
--- llvm/lib/Target/X86/README.txt:1.45 Thu Feb 2 13:43:28 2006
+++ llvm/lib/Target/X86/README.txt Fri Feb 3 00:22:11 2006
@@ -76,11 +76,6 @@
//===---------------------------------------------------------------------===//
-Should support emission of the bswap instruction, probably by adding a new
-DAG node for byte swapping. Also useful on PPC which has byte-swapping loads.
-
-//===---------------------------------------------------------------------===//
-
Compile this:
_Bool f(_Bool a) { return a!=1; }
@@ -168,45 +163,6 @@
//===---------------------------------------------------------------------===//
-For all targets, not just X86:
-When llvm.memcpy, llvm.memset, or llvm.memmove are lowered, they should be
-optimized to a few store instructions if the source is constant and the length
-is smallish (< 8). This will greatly help some tests like Shootout/strcat.c
-
-//===---------------------------------------------------------------------===//
-
-Solve this DAG isel folding deficiency:
-
-int X, Y;
-
-void fn1(void)
-{
- X = X | (Y << 3);
-}
-
-compiles to
-
-fn1:
- movl Y, %eax
- shll $3, %eax
- orl X, %eax
- movl %eax, X
- ret
-
-The problem is the store's chain operand is not the load X but rather
-a TokenFactor of the load X and load Y, which prevents the folding.
-
-There are two ways to fix this:
-
-1. The dag combiner can start using alias analysis to realize that y/x
- don't alias, making the store to X not dependent on the load from Y.
-2. The generated isel could be made smarter in the case it can't
- disambiguate the pointers.
-
-Number 1 is the preferred solution.
-
-//===---------------------------------------------------------------------===//
-
The instruction selector sometimes misses folding a load into a compare. The
pattern is written as (cmp reg, (load p)). Because the compare isn't
commutative, it is not matched with the load on both sides. The dag combiner
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