1. (((x) & 0xFF00) >> 8) | (((x) & 0x00FF) << 8)
=> (bswap x) >> 16
2. ((x&0xff)<<8)|((x&0xff00)>>8)|((x&0xff000000)>>8)|((x&0x00ff0000)<<8))
=> (rotl (bswap x) 16)
This allows us to eliminate most of the def : Pat patterns for ARM rev16
revsh instructions. It catches many more cases for ARM and x86.
rdar://9609108
llvm-svn: 133503
ops.
This is a rewrite of the IV simplification algorithm used by
-disable-iv-rewrite. To avoid perturbing the default mode, I
temporarily split the driver and created SimplifyIVUsersNoRewrite. The
idea is to avoid doing opcode/pattern matching inside
IndVarSimplify. SCEV already does it. We want to optimize with the
full generality of SCEV, but optimize def-use chains top down on-demand rather
than rewriting the entire expression bottom-up. This was easy to do
for operations that SCEV can prove are identity function. So we're now
eliminating bitmasks and zero extends this way.
A result of this rewrite is that indvars -disable-iv-rewrite no longer
requires IVUsers.
llvm-svn: 133502
The current implementation generates stack loads/stores, which are
really just mov instructions from/to "special" registers. This may
not be the most efficient implementation, compared to an approach where
the stack registers are directly folded into instructions, but this is
easier to implement and I have yet to see a case where ptxas is unable
to see through this kind of register usage and know what is really
going on.
llvm-svn: 133443
Change PHINodes to store simple pointers to their incoming basic blocks,
instead of full-blown Uses.
Note that this loses an optimization in SplitCriticalEdge(), because we
can no longer walk the use list of a BasicBlock to find phi nodes. See
the comment I removed starting "However, the foreach loop is slow for
blocks with lots of predecessors".
Extend replaceAllUsesWith() on a BasicBlock to also update any phi
nodes in the block's successors. This mimics what would have happened
when PHINodes were proper Users of their incoming blocks. (Note that
this only works if OldBB->replaceAllUsesWith(NewBB) is called when
OldBB still has a terminator instruction, so it still has some
successors.)
llvm-svn: 133435
Change various bits of code to make better use of the existing PHINode
API, to insulate them from forthcoming changes in how PHINodes store
their operands.
llvm-svn: 133434
I don't think the AugmentedUse struct buys us much, either in
correctness or in ease of use. Ditch it, and simplify Use::getUser() and
User::allocHungoffUses().
llvm-svn: 133433
* Don't introduce a duplicated bb in the CFG
* When making a branch unconditional, clear the PredCond array so that it
is really unconditional.
llvm-svn: 133432
dragonegg buildbots back to life. Original commit message:
Teach early dup how to duplicate basic blocks with one successor and only phi instructions
into more complex blocks.
llvm-svn: 133430
all over the place in different styles and variants. Standardize on two
preferred entrypoints: one that takes a StructType and ArrayRef, and one that
takes StructType and varargs.
In cases where there isn't a struct type convenient, we now add a
ConstantStruct::getAnon method (whose name will make more sense after a few
more patches land).
It would be "really really nice" if the ConstantStruct::get and
ConstantVector::get methods didn't make temporary std::vectors.
llvm-svn: 133412
top level type without a specified number. This asmprinter has never
generated this, as you can tell by no tests being updated. It also isn't
documented.
llvm-svn: 133368
In cases such as the attached test, where the case value for a switch
destination is used in a phi node that follows the destination, it
might be better to replace that value with the condition value of the
switch, so that more blocks can be folded away with
TryToSimplifyUncondBranchFromEmptyBlock because there are less
conflicts in the phi node.
llvm-svn: 133344
type's bitwidth matches the (allocated) size of the alloca. This severely
pessimizes vector scalar replacement when the only vector type being used is
something like <3 x float> on x86 or ARM whose allocated size matches a
<4 x float>.
I hope to fix some of the flawed assumptions about allocated size throughout
scalar replacement and reenable this in most cases.
llvm-svn: 133338
for pre-2.9 bitcode files. We keep x86 unaligned loads, movnt, crc32, and the
target indep prefetch change.
As usual, updating the testsuite is a PITA.
llvm-svn: 133337
The LSDA is a bit difficult for the non-initiated to read. Even with comments,
it's not always clear what's going on. This wraps the ASM streamer in a class
that retains the LSDA and then emits a human-readable description of what's
going on in it.
So instead of having to make sense of:
Lexception1:
.byte 255
.byte 155
.byte 168
.space 1
.byte 3
.byte 26
Lset0 = Ltmp7-Leh_func_begin1
.long Lset0
Lset1 = Ltmp812-Ltmp7
.long Lset1
Lset2 = Ltmp913-Leh_func_begin1
.long Lset2
.byte 3
Lset3 = Ltmp812-Leh_func_begin1
.long Lset3
Lset4 = Leh_func_end1-Ltmp812
.long Lset4
.long 0
.byte 0
.byte 1
.byte 0
.byte 2
.byte 125
.long __ZTIi@GOTPCREL+4
.long __ZTIPKc@GOTPCREL+4
you can read this instead:
## Exception Handling Table: Lexception1
## @LPStart Encoding: omit
## @TType Encoding: indirect pcrel sdata4
## @TType Base: 40 bytes
## @CallSite Encoding: udata4
## @Action Table Size: 26 bytes
## Action 1:
## A throw between Ltmp7 and Ltmp812 jumps to Ltmp913 on an exception.
## For type(s): __ZTIi@GOTPCREL+4 __ZTIPKc@GOTPCREL+4
## Action 2:
## A throw between Ltmp812 and Leh_func_end1 does not have a landing pad.
llvm-svn: 133286
* We should change the generated code because of a debug use.
* Avoid creating debug uses of undef, as they become a kill.
Test to follow.
llvm-svn: 133255
* rounding modes for fp add, mul, sub now use .rn
* float -> int rounding correctly uses .rzi not .rni
* 32bit fdiv for sm13 uses div.rn (instead of div.approx)
* 32bit fdiv for sm10 now uses div (instead of div.approx)
Approx is not IEEE 754 compatible (and should be optionally set by a flag to the backend instead). The .rn rounding modifier is the PTX default anyway, but it's better to be explicit.
All these modifiers should be available by using __fmul_rz functions for example, but support will need to be added for this in the backend.
Patch by Dan Bailey
llvm-svn: 133253
