diff options
author | Chris Lattner <sabre@nondot.org> | 2006-05-05 05:36:15 +0000 |
---|---|---|
committer | Chris Lattner <sabre@nondot.org> | 2006-05-05 05:36:15 +0000 |
commit | 55c63257f31e2fa0b4a606f15d809cf615bc960c (patch) | |
tree | 72b59759009232c2d2744bda2ffbcd77b6f0b604 /lib/Target/PowerPC/README.txt | |
parent | 4b75e73791f32f73ca1fc91f073a5126e6700b7a (diff) | |
download | llvm-55c63257f31e2fa0b4a606f15d809cf615bc960c.tar.gz llvm-55c63257f31e2fa0b4a606f15d809cf615bc960c.tar.bz2 llvm-55c63257f31e2fa0b4a606f15d809cf615bc960c.tar.xz |
New note, Nate, please check to see if I'm full of it :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28118 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/PowerPC/README.txt')
-rw-r--r-- | lib/Target/PowerPC/README.txt | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt index 6b3988dfb9..bbe311cb38 100644 --- a/lib/Target/PowerPC/README.txt +++ b/lib/Target/PowerPC/README.txt @@ -559,3 +559,36 @@ transformation, good for PI. See PPCISelLowering.cpp, this comment: // need to flag these together so that the value isn't live across a call. //setOperationAction(ISD::SINT_TO_FP, MVT::i32, Custom); +===-------------------------------------------------------------------------=== + +Another missed rlwimi case: + +void %foo(uint *%tmp) { + %tmp = load uint* %tmp ; <uint> [#uses=3] + %tmp1 = shr uint %tmp, ubyte 31 ; <uint> [#uses=1] + %tmp1 = cast uint %tmp1 to ubyte ; <ubyte> [#uses=1] + %tmp4.mask = shr uint %tmp, ubyte 30 ; <uint> [#uses=1] + %tmp4.mask = cast uint %tmp4.mask to ubyte ; <ubyte> [#uses=1] + %tmp = or ubyte %tmp4.mask, %tmp1 ; <ubyte> [#uses=1] + %tmp10 = cast ubyte %tmp to uint ; <uint> [#uses=1] + %tmp11 = shl uint %tmp10, ubyte 31 ; <uint> [#uses=1] + %tmp12 = and uint %tmp, 2147483647 ; <uint> [#uses=1] + %tmp13 = or uint %tmp11, %tmp12 ; <uint> [#uses=1] + store uint %tmp13, uint* %tmp + ret void +} + +We emit: + +_foo: + lwz r2, 0(r3) + srwi r4, r2, 30 + srwi r5, r2, 31 + or r4, r4, r5 + slwi r4, r4, 31 + rlwimi r4, r2, 0, 1, 31 + stw r4, 0(r3) + blr + +I *think* that could use another rlwimi. + |