Commit Graph

8 Commits

Author SHA1 Message Date
Nicolai Haehnle 84c9f9919a Add writeonly IR attribute
Summary:
This complements the earlier addition of IntrWriteMem and IntrWriteArgMem
LLVM intrinsic properties, see D18291.

Also start using the attribute for memset, memcpy, and memmove intrinsics,
and remove their special-casing in BasicAliasAnalysis.

Reviewers: reames, joker.eph

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D18714

llvm-svn: 274485
2016-07-04 08:01:29 +00:00
Vaivaswatha Nagaraj fb3f4907c0 Add InaccessibleMemOnly and inaccessibleMemOrArgMemOnly attributes
Summary:
This patch introduces two new function attributes 

InaccessibleMemOnly: This attribute indicates that the function may only access memory that is not accessible by the program/IR being compiled. This is a weaker form of ReadNone.
inaccessibleMemOrArgMemOnly: This attribute indicates that the function may only access memory that is either not accessible by the program/IR being compiled, or is pointed to by its pointer arguments. This is a weaker form of  ArgMemOnly

Test cases have been updated. This revision uses this (d001932f3a) as reference.

Reviewers: jmolloy, hfinkel

Subscribers: reames, joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D15499

llvm-svn: 255778
2015-12-16 16:16:19 +00:00
James Molloy e6f87ca812 Add a new attribute: norecurse
This attribute allows the compiler to assume that the function never recurses into itself, either directly or indirectly (transitively). This can be used among other things to demote global variables to locals.

llvm-svn: 252282
2015-11-06 10:32:53 +00:00
Duncan P. N. Exon Smith a6b8895442 llvm-dis: Stop crashing when dropping debug info
Since r199356, we've printed a warning when dropping debug info.
r225562 started crashing on that, since it registered a diagnostic
handler that only expected errors.  This fixes the handler to expect
other severities.  As a side effect, it now prints "error: " at the
start of error messages, similar to `llvm-as`.

There was a testcase for r199356, but it only really checked the
assembler.  Move `test/Bitcode/drop-debug-info.ll` to `test/Assembler`,
and introduce `test/Bitcode/drop-debug-info.3.5.ll` (and companion
`.bc`) to test the bitcode reader.

Note: tools/gold/gold-plugin.cpp has an equivalent bug, but I'm not sure
what the best fix is there.  I'll file a PR.

llvm-svn: 230416
2015-02-25 01:10:03 +00:00
Rafael Espindola d0b23bef6f Use the DiagnosticHandler to print diagnostics when reading bitcode.
The bitcode reading interface used std::error_code to report an error to the
callers and it is the callers job to print diagnostics.

This is not ideal for error handling or diagnostic reporting:

* For error handling, all that the callers care about is 3 possibilities:
  * It worked
  * The bitcode file is corrupted/invalid.
  * The file is not bitcode at all.

* For diagnostic, it is user friendly to include far more information
  about the invalid case so the user can find out what is wrong with the
  bitcode file. This comes up, for example, when a developer introduces a
  bug while extending the format.

The compromise we had was to have a lot of error codes.

With this patch we use the DiagnosticHandler to communicate with the
human and std::error_code to communicate with the caller.

This allows us to have far fewer error codes and adds the infrastructure to
print better diagnostics. This is so because the diagnostics are printed when
he issue is found. The code that detected the problem in alive in the stack and
can pass down as much context as needed. As an example the patch updates
test/Bitcode/invalid.ll.

Using a DiagnosticHandler also moves the fatal/non-fatal error decision to the
caller. A simple one like llvm-dis can just use fatal errors. The gold plugin
needs a bit more complex treatment because of being passed non-bitcode files. An
hypothetical interactive tool would make all bitcode errors non-fatal.

llvm-svn: 225562
2015-01-10 00:07:30 +00:00
Rafael Espindola 48da4f4691 Change BitcodeReader to use error_code instead of bool + string.
In order to create an ObjectFile implementation that uses bitcode files, we
need to propagate the bitcode errors to the ObjectFile interface, so we need
to convert it to use the same error handling as ObjectFile: error_code.

llvm-svn: 193996
2013-11-04 16:16:24 +00:00
NAKAMURA Takumi 160cef8ddc llvm/test/Bitcode/invalid.ll: Tweak expresion to mach "llvm-dis.EXE:"
llvm-svn: 193738
2013-10-31 06:21:00 +00:00
Rafael Espindola 26b43cac18 Fix a use after free on invalid input.
llvm-svn: 193737
2013-10-31 04:20:23 +00:00