Owen Anderson
96b9e5423a
Add support for eliminating memcpy's at the end of functions. Also fix some errors I noticed in
...
the handling of eliminating stores to byval arguments.
llvm-svn: 46494
2008-01-29 06:18:36 +00:00
Devang Patel
86ff705c22
Filter loops that subtract induction variables.
...
These loops are not yet handled.
Fix PR 1912.
llvm-svn: 46484
2008-01-29 02:20:41 +00:00
Chris Lattner
dc0c4352bd
Transform calls to memcpy into llvm.memcpy calls, patch by Eli Friedman.
...
llvm-svn: 46433
2008-01-28 04:41:43 +00:00
Nick Lewycky
6b070b1b93
Handle some more combinations of extend and icmp. Fixes PR1940.
...
llvm-svn: 46431
2008-01-28 03:48:02 +00:00
Chris Lattner
359756ea4b
Fix PR1932 by disabling an xform invalid for fdiv.
...
llvm-svn: 46429
2008-01-28 00:58:18 +00:00
Chris Lattner
7250586ec9
Fix PR1938 by forcing the code that uses an undefined value to branch one
...
way or the other. Rewriting the code itself prevents subsequent analysis
passes from making contradictory conclusions about the code that could
cause an infeasible path to be made feasible.
llvm-svn: 46427
2008-01-28 00:32:30 +00:00
Nick Lewycky
cd28ef8950
Be more careful modifying the use_list while also iterating through it.
...
llvm-svn: 46417
2008-01-27 18:35:00 +00:00
Duncan Sands
e77256b325
Revert r46393: readonly/readnone functions are no
...
longer allowed to write through byval arguments.
llvm-svn: 46416
2008-01-27 18:12:58 +00:00
Bill Wendling
629a569ce9
The CorrelatedExpressionElimination pass is known to be buggy. Remove it.
...
This fixes PR1769.
llvm-svn: 46408
2008-01-27 06:11:41 +00:00
Chris Lattner
aa553aa0c1
Fold fptrunc(add (fpextend x), (fpextend y)) -> add(x,y), as GCC does.
...
llvm-svn: 46406
2008-01-27 05:29:54 +00:00
Bill Wendling
1c92468074
If there are no machine instructions emitted for a function, then insert
...
a "nop" instruction so that we don't have the function's label associated
with something that it's not supposed to be associated with.
llvm-svn: 46394
2008-01-26 06:51:24 +00:00
Duncan Sands
792234c366
Create an explicit copy for byval parameters even
...
when inlining a readonly function.
llvm-svn: 46393
2008-01-26 06:41:49 +00:00
Bill Wendling
1e56a2ffb6
If we have a function like this:
...
void bork() {
int *address = 0;
*address = 0;
}
It's compiled into LLVM code that looks like this:
define void @bork() noreturn nounwind {
entry:
unreachable
}
This is bad on some platforms (like PPC) because it will generate the label for
the function but no body. The label could end up being associated with some
non-code related stuff, like a section. This places a "trap" instruction if the
SimplifyCFG pass removed all code from the function leaving only one
"unreachable" instruction.
llvm-svn: 46387
2008-01-26 01:43:44 +00:00
Duncan Sands
10316ffbb2
Do this more neatly.
...
llvm-svn: 46369
2008-01-25 22:06:51 +00:00
Owen Anderson
a4ff15c69f
DeadStoreElimination can treat byval parameters as if there were alloca's for the purpose of removing end-of-function stores.
...
llvm-svn: 46351
2008-01-25 10:10:33 +00:00
Nick Lewycky
13b6bc91d6
Enable the fix I just checked in, silly me.
...
llvm-svn: 46247
2008-01-22 05:42:02 +00:00
Nick Lewycky
78780f175b
Multiply can be evaluated in a different type, so long as the target type has
...
a smaller bitwidth.
llvm-svn: 46244
2008-01-22 05:08:48 +00:00
Duncan Sands
8a2778c20e
Make sure the caller doesn't use freed memory.
...
Fixes PR1935.
llvm-svn: 46203
2008-01-20 16:51:46 +00:00
Duncan Sands
85db5b21a7
Initializing an unsigned with ~0UL causes the compiler
...
to complain on x86-64 (gcc 4.1). Use ~0U instead.
llvm-svn: 46197
2008-01-20 10:49:23 +00:00
Evan Cheng
c187163bab
DAE bug fix. Don't lose parameter attributes on vararg arguments.
...
llvm-svn: 46113
2008-01-17 04:18:54 +00:00
Chris Lattner
c32be7e6b2
Fix arg promotion to propagate the correct attrs on the calls to
...
promoted functions. This is important for varargs calls in
particular. Thanks to duncan for providing a great testcase.
llvm-svn: 46108
2008-01-17 01:17:03 +00:00
Chris Lattner
81a39bb7ba
Handle attribute(used) global variables that are i8.
...
llvm-svn: 46090
2008-01-16 21:35:43 +00:00
Devang Patel
a8d63b0b30
Do not strip llvm.used values.
...
llvm-svn: 46045
2008-01-16 03:33:05 +00:00
Duncan Sands
81e35b4d47
I noticed that the trampoline straightening transformation could
...
drop attributes on varargs call arguments. Also, it could generate
invalid IR if the transformed call already had the 'nest' attribute
somewhere (this can never happen for code coming from llvm-gcc,
but it's a theoretical possibility). Fix both problems.
llvm-svn: 45973
2008-01-14 19:52:09 +00:00
Chris Lattner
efb498eddb
Fix the miscompilation of MiBench/consumer-lame that was exposed by Evan's
...
byval work. This miscompilation is due to the program indexing an array out
of range and us doing a transformation that broke this.
llvm-svn: 45949
2008-01-14 02:09:12 +00:00
Chris Lattner
5d135cc20a
The isNotSuitableForSRA property is now dead, don't compute it.
...
llvm-svn: 45948
2008-01-14 01:32:52 +00:00
Chris Lattner
760b05a331
Change SRAGlobal to not depend on isNotSuitableForSRA, which makes it very
...
difficult to understand the invariants.
llvm-svn: 45947
2008-01-14 01:31:05 +00:00
Chris Lattner
c2933482a0
Make the 'shrink global to bool' optimization more self contained, and thus
...
easier to show that its safe. No functionality change.
llvm-svn: 45946
2008-01-14 01:17:44 +00:00
Chris Lattner
d22a5f6314
Turn a memcpy from a double* into a load/store of double instead of
...
a load/store of i64. The later prevents promotion/scalarrepl of the
source and dest in many cases.
This fixes the 300% performance regression of the byval stuff on
stepanov_v1p2.
llvm-svn: 45945
2008-01-14 00:28:35 +00:00
Chris Lattner
8560bb9d98
factor memcpy/memmove simplification out to its own SimplifyMemTransfer
...
method, no functionality change.
llvm-svn: 45944
2008-01-13 23:50:23 +00:00
Chris Lattner
5fbf76aaf4
simplify some code. If we can infer alignment for source and dest that are
...
greater than memcpy alignment, and if we lower to load/store, use the best
alignment info we have.
llvm-svn: 45943
2008-01-13 22:30:28 +00:00
Chris Lattner
4f69f1a721
simplify some code by adding a InsertBitCastBefore method,
...
make memmove->memcpy conversion a bit simpler.
llvm-svn: 45942
2008-01-13 22:23:22 +00:00
Chris Lattner
32eae5daa5
Fix PR1907, a nasty miscompilation because instcombine didn't
...
realize that ne & sgt was a signed comparison (it was only
looking at whether the left compare was signed).
llvm-svn: 45937
2008-01-13 20:59:02 +00:00
Duncan Sands
560625b701
Small simplification.
...
llvm-svn: 45932
2008-01-13 08:12:17 +00:00
Duncan Sands
7414cc131b
When turning a call to a bitcast function into a direct call,
...
if this becomes a varargs call then deal correctly with any
parameter attributes on the newly vararg call arguments.
llvm-svn: 45931
2008-01-13 08:02:44 +00:00
Chris Lattner
d90840eddc
we don't have to make an explicit copy of a byval argument when
...
inlining a function if we know that the function does not write
to *any* memory. This implements test/Transforms/Inline/byval2.ll
llvm-svn: 45912
2008-01-12 18:54:29 +00:00
Chris Lattner
fb5876f0be
Allow clients to specify the inline threshold when creating
...
the inliner pass. Patch by Robert Zeh.
llvm-svn: 45903
2008-01-12 06:49:13 +00:00
Duncan Sands
6f49217a5e
When DAE drops the varargs part of a function, ensure any
...
attributes on the vararg call arguments are also dropped.
llvm-svn: 45892
2008-01-11 23:13:45 +00:00
Chris Lattner
a1246ba8ed
Teach argpromote to ruthlessly hack small byval structs when it can
...
get away with it, which exposes opportunities to eliminate the memory
objects entirely. For example, we now compile byval.ll to:
define internal void @f1(i32 %b.0, i64 %b.1) {
entry:
%tmp2 = add i32 %b.0, 1 ; <i32> [#uses=0]
ret void
}
define i32 @main() nounwind {
entry:
call void @f1( i32 1, i64 2 )
ret i32 0
}
This seems like it would trigger a lot for code that passes around small
structs (e.g. SDOperand's or _Complex)...
llvm-svn: 45886
2008-01-11 22:31:41 +00:00
Chris Lattner
8644bdca87
Use smallptrset instead of std::set for efficiency.
...
llvm-svn: 45878
2008-01-11 19:36:30 +00:00
Chris Lattner
44aaf42d14
a byval argument is guaranteed to be valid to load.
...
llvm-svn: 45877
2008-01-11 19:34:32 +00:00
Chris Lattner
129a0e4f7d
Update this code to use eraseFromParent where possible. Compute
...
whether an argument is byval and pass into isSafeToPromoteArgument.
llvm-svn: 45876
2008-01-11 19:20:39 +00:00
Chris Lattner
85a0b511cc
replace a loop with a constant time check.
...
llvm-svn: 45875
2008-01-11 18:55:10 +00:00
Chris Lattner
c9666b967f
another minor datastructure tweak.
...
llvm-svn: 45874
2008-01-11 18:47:45 +00:00
Chris Lattner
a6b0783f14
start using smallvector to avoid vector heap thrashing.
...
llvm-svn: 45873
2008-01-11 18:43:58 +00:00
Chris Lattner
bf51fecdc4
When inlining a functino with a byval argument, make an explicit
...
copy of it in case the callee modifies the struct.
llvm-svn: 45853
2008-01-11 06:09:30 +00:00
Chris Lattner
67f581b344
Implement PR1795, an instcombine hack for forming GEPs with integer pointer arithmetic.
...
llvm-svn: 45745
2008-01-08 07:23:51 +00:00
Duncan Sands
7955cf0cd7
Small cleanup for handling of type/parameter attribute
...
incompatibility.
llvm-svn: 45704
2008-01-07 17:16:06 +00:00
Gordon Henriksen
f0803127c6
Deleting an empty file. Thanks, /usr/bin/patch!
...
llvm-svn: 45675
2008-01-07 02:29:04 +00:00
Gordon Henriksen
db4f51e1b9
With this patch, the LowerGC transformation becomes the
...
ShadowStackCollector, which additionally has reduced overhead with
no sacrifice in portability.
Considering a function @fun with 8 loop-local roots,
ShadowStackCollector introduces the following overhead
(x86):
; shadowstack prologue
movl L_llvm_gc_root_chain$non_lazy_ptr, %eax
movl (%eax), %ecx
movl $___gc_fun, 20(%esp)
movl $0, 24(%esp)
movl $0, 28(%esp)
movl $0, 32(%esp)
movl $0, 36(%esp)
movl $0, 40(%esp)
movl $0, 44(%esp)
movl $0, 48(%esp)
movl $0, 52(%esp)
movl %ecx, 16(%esp)
leal 16(%esp), %ecx
movl %ecx, (%eax)
; shadowstack loop overhead
(none)
; shadowstack epilogue
movl 48(%esp), %edx
movl %edx, (%ecx)
; shadowstack metadata
.align 3
___gc_fun: # __gc_fun
.long 8
.space 4
In comparison to LowerGC:
; lowergc prologue
movl L_llvm_gc_root_chain$non_lazy_ptr, %eax
movl (%eax), %ecx
movl %ecx, 48(%esp)
movl $8, 52(%esp)
movl $0, 60(%esp)
movl $0, 56(%esp)
movl $0, 68(%esp)
movl $0, 64(%esp)
movl $0, 76(%esp)
movl $0, 72(%esp)
movl $0, 84(%esp)
movl $0, 80(%esp)
movl $0, 92(%esp)
movl $0, 88(%esp)
movl $0, 100(%esp)
movl $0, 96(%esp)
movl $0, 108(%esp)
movl $0, 104(%esp)
movl $0, 116(%esp)
movl $0, 112(%esp)
; lowergc loop overhead
leal 44(%esp), %eax
movl %eax, 56(%esp)
leal 40(%esp), %eax
movl %eax, 64(%esp)
leal 36(%esp), %eax
movl %eax, 72(%esp)
leal 32(%esp), %eax
movl %eax, 80(%esp)
leal 28(%esp), %eax
movl %eax, 88(%esp)
leal 24(%esp), %eax
movl %eax, 96(%esp)
leal 20(%esp), %eax
movl %eax, 104(%esp)
leal 16(%esp), %eax
movl %eax, 112(%esp)
; lowergc epilogue
movl 48(%esp), %edx
movl %edx, (%ecx)
; lowergc metadata
(none)
llvm-svn: 45670
2008-01-07 01:30:53 +00:00