Follow-up to r219534 to make symbolization more robust.

1) Explicitly provide important arguments to llvm-symbolizer,
not relying on defaults.
2) Be more defensive about symbolizer output.

This might fix weird failures on ninja-x64-msvc-RA-centos6 buildbot.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219541 91177308-0d34-0410-b5e6-96231b3b80d8
Return undef on FP <-> Int conversions that overflow (PR21330).

The LLVM Lang Ref states for signed/unsigned int to float conversions:
"If the value cannot fit in the floating point value, the results are undefined."

And for FP to signed/unsigned int:
"If the value cannot fit in ty2, the results are undefined."

This matches the C definitions.

The existing behavior pins to infinity or a max int value, but that may just
lead to more confusion as seen in:
http://llvm.org/bugs/show_bug.cgi?id=21130

Returning undef will hopefully lead to a less silent failure.

Differential Revision: http://reviews.llvm.org/D5603



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219542 91177308-0d34-0410-b5e6-96231b3b80d8
[MCJIT] Replace memcpy with readBytesUnaligned in RuntimeDyldMachOI386.

This should fix the failures of the MachO_i386_DynNoPIC_relocations.s test case
on MIPS hosts.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219543 91177308-0d34-0410-b5e6-96231b3b80d8
[SCEV] Add some asserts to the recently improved trip count computation
routines and fix all of the bugs they expose.

I hit a test case that crashed even without these asserts due to passing
a non-exiting latch to the ExitingBlock parameter of the trip count
computation machinery. However, when I add the nice asserts, it turns
out we have plenty of coverage of these bugs, they just didn't manifest
in crashers.

The core problem seems to stem from an assumption that the latch *is*
the exiting block. While this is often true, and somewhat the "normal"
way to think about loops, it isn't necessarily true. The correct way to
call the trip count routines in a *generic* fashion (that is, without
a particular exit in mind) is to just use the loop's single exiting
block if it has one. The trip count can't be computed generically unless
it does. This works great for the loop vectorizer. The loop unroller
actually *wants* to select the latch when it has to chose between
multiple exits because for unrolling it is the latch trips that matter.
But if this is the desire, it needs to explicitly guard for non-exiting
latches and check for the generic trip count in that case.

I've added the asserts, and added convenience APIs for querying the trip
count generically that check for a single exit block. I've kept the APIs
consistent between computing trip count and trip multiples.

Thansk to Mark for the help debugging and tracking down the *right* fix
here!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219550 91177308-0d34-0410-b5e6-96231b3b80d8
Add basic conditional branches in mips fast-isel

Summary: Implement the most basic form of conditional branches in Mips fast-isel.

Test Plan:
br1.ll
run 4 flavors of test-suite. mips32 r1/r2 and at -O0/O2

Reviewers: dsanders

Reviewed By: dsanders

Subscribers: llvm-commits, rfuhler

Differential Revision: http://reviews.llvm.org/D5583

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219556 91177308-0d34-0410-b5e6-96231b3b80d8
Guard the definition of the stack tracing function with the same macros
that guard its usage. Without this, we can get unused function warnings
when backtraces are disabled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219558 91177308-0d34-0410-b5e6-96231b3b80d8
[SCEV] Fix one more caller blindly passing the latch to SCEV's
getSmallConstantTripCount even when it isn't the exiting block.

I missed this in my first audit, very sorry. This was found in LNT and
elsewhere. I don't have a test case, but it was completely obvious from
inspection that this was the problem. I'll see if I can reduce a test
case, but I'm not really hopeful, and the value seems quite low.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219562 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine: mul to shl shouldn't preserve nsw

consider:
mul i32 nsw %x, -2147483648

this instruction will not result in poison if %x is 1

however, if we transform this into:
shl i32 nsw %x, 31

then we will be generating poison because we just shifted into the sign
bit.

This fixes PR21242.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219566 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine, InstSimplify: (%X /s C1) /s C2 isn't always 0 when C1 * C2 overflow

consider:
C1 = INT_MIN
C2 = -1

C1 * C2 overflows without a doubt but consider the following:
%x = i32 INT_MIN

This means that (%X /s C1) is 1 and (%X /s C1) /s C2 is -1.

N. B.  Move the unsigned version of this transform to InstSimplify, it
doesn't create any new instructions.

This fixes PR21243.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219567 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine: Don't fold (X <<s log(INT_MIN)) /s INT_MIN to X

Consider the case where X is 2.  (2 <<s 31)/s-2147483648 is zero but we
would fold to X.  Note that this is valid when we are in the unsigned
domain because we require NUW: 2 <<u 31 results in poison.

This fixes PR21245.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219568 91177308-0d34-0410-b5e6-96231b3b80d8
Test commit access

Fix comment typo + spelling.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219572 91177308-0d34-0410-b5e6-96231b3b80d8
MC: Bit pack MCSymbolData.

On x86_64 this brings it from 80 bytes to 64 bytes. Also make any member
variables private and clean up uses to go through the existing accessors.

NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219573 91177308-0d34-0410-b5e6-96231b3b80d8
MC: Shrink MCSymbolRefExpr by only storing the bits we need.

32 -> 16 bytes on x86_64. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219574 91177308-0d34-0410-b5e6-96231b3b80d8
AssumptionTracker: Don't create temporary CallbackVHs.

Those are expensive to create in cold cache scenarios. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219575 91177308-0d34-0410-b5e6-96231b3b80d8
Test commit access (email fix)

Indentation tidyup.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219577 91177308-0d34-0410-b5e6-96231b3b80d8
Suppress llvm-ar's MRI tests for now on win32, since line_iterator is incompatible to CRLF.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219579 91177308-0d34-0410-b5e6-96231b3b80d8
llvm/test/CodeGen: Some tests don't REQUIRE asserts any more. Remove them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219581 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine: Simplify commonIDivTransforms

A helper routine, MultiplyOverflows, was a less efficient
reimplementation of APInt's smul_ov and umul_ov.  While we are here,
clean up the code so it's more uniform.

No functionality change intended.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219583 91177308-0d34-0410-b5e6-96231b3b80d8
[X86] Memory folding for commutative instructions.

This patch improves support for commutative instructions in the x86 memory folding implementation by attempting to fold a commuted version of the instruction if the original folding fails - if that folding fails as well the instruction is 're-commuted' back to its original order before returning.

This mainly helps the stack inliner better fold reloads of 3 (or more) operand instructions (VEX encoded SSE etc.) but by performing this in the lowest foldMemoryOperandImpl implementation it also replaces the X86InstrInfo::optimizeLoadInstr version and is now used by FastISel too.

Differential Revision: http://reviews.llvm.org/D5701


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219584 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine: Turn (x != 0 & x <u C) into the canonical range check form (x-1 <u C-1)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219585 91177308-0d34-0410-b5e6-96231b3b80d8