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| author | Dan Gohman <gohman@apple.com> | 2007-10-09 15:42:21 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2007-10-09 15:42:21 +0000 |
| commit | 6d28778bfdde28f213d912e1a98e04c1b3696d8b (patch) | |
| tree | 710ac87b095806df271586e81d0fed5247f763af /llvm | |
| parent | 678387a29934c5af2cf973ef859eddf42f85451f (diff) | |
| download | bcm5719-llvm-6d28778bfdde28f213d912e1a98e04c1b3696d8b.tar.gz bcm5719-llvm-6d28778bfdde28f213d912e1a98e04c1b3696d8b.zip | |
This is done.
llvm-svn: 42785
Diffstat (limited to 'llvm')
| -rw-r--r-- | llvm/lib/Target/X86/README.txt | 30 |
1 files changed, 0 insertions, 30 deletions
diff --git a/llvm/lib/Target/X86/README.txt b/llvm/lib/Target/X86/README.txt index 807a921ac78..9bafff73d5c 100644 --- a/llvm/lib/Target/X86/README.txt +++ b/llvm/lib/Target/X86/README.txt @@ -10,36 +10,6 @@ http://softwarecommunity.intel.com/isn/Downloads/Intel%20SSE4%20Programming%20Re //===---------------------------------------------------------------------===// -Add a MUL2U and MUL2S nodes to represent a multiply that returns both the -Hi and Lo parts (combination of MUL and MULH[SU] into one node). Add this to -X86, & make the dag combiner produce it when needed. This will eliminate one -imul from the code generated for: - -long long test(long long X, long long Y) { return X*Y; } - -by using the EAX result from the mul. We should add a similar node for -DIVREM. - -another case is: - -long long test(int X, int Y) { return (long long)X*Y; } - -... which should only be one imul instruction. - -or: - -unsigned long long int t2(unsigned int a, unsigned int b) { - return (unsigned long long)a * b; -} - -... which should be one mul instruction. - - -This can be done with a custom expander, but it would be nice to move this to -generic code. - -//===---------------------------------------------------------------------===// - CodeGen/X86/lea-3.ll:test3 should be a single LEA, not a shift/move. The X86 backend knows how to three-addressify this shift, but it appears the register allocator isn't even asking it to do so in this case. We should investigate |

