remove some target-indep and implemented notes

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25930 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 11 insertions, 57 deletions

diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index fb52dd3b96..42d701ef01 100644
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -92,6 +92,17 @@ http://gcc.gnu.org/ml/gcc-patches/2006-02/msg00133.html
 
 ===-------------------------------------------------------------------------===
 
+PIC Code Gen IPO optimization:
+
+Squish small scalar globals together into a single global struct, allowing the 
+address of the struct to be CSE'd, avoiding PIC accesses (also reduces the size
+of the GOT on targets with one).
+
+Note that this is discussed here for GCC:
+http://gcc.gnu.org/ml/gcc-patches/2006-02/msg00133.html
+
+===-------------------------------------------------------------------------===
+
 Implement Newton-Rhapson method for improving estimate instructions to the
 correct accuracy, and implementing divide as multiply by reciprocal when it has
 more than one use.  Itanium will want this too.
@@ -351,14 +362,6 @@ just fastcc.
 
 ===-------------------------------------------------------------------------===
 
-Code Gen IPO optimization:
-
-Squish small scalar globals together into a single global struct, allowing the 
-address of the struct to be CSE'd, avoiding PIC accesses (also reduces the size
-of the GOT on targets with one).
-
-===-------------------------------------------------------------------------===
-
 Generate lwbrx and other byteswapping load/store instructions when reasonable.
 
 ===-------------------------------------------------------------------------===
@@ -473,11 +476,6 @@ _foo:
 
 ===-------------------------------------------------------------------------===
 
-Get the C front-end to expand hypot(x,y) -> llvm.sqrt(x*x+y*y) when errno and
-precision don't matter (ffastmath).  Misc/mandel will like this. :)
-
-===-------------------------------------------------------------------------===
-
 Fold add and sub with constant into non-extern, non-weak addresses so this:
 
 static int a;
diff --git a/lib/Target/X86/README.txt b/lib/Target/X86/README.txt
index 3b24b4a3f3..b1b3428c59 100644
--- a/lib/Target/X86/README.txt
+++ b/lib/Target/X86/README.txt
@@ -76,11 +76,6 @@ Another useful one would be  ~0ULL >> X and ~0ULL << X.
 
 //===---------------------------------------------------------------------===//
 
-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 @@ Combine: a = sin(x), b = cos(x) into a,b = sincos(x).
 
 //===---------------------------------------------------------------------===//
 
-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