Commit Graph

7 Commits

Author SHA1 Message Date
Sanjay Patel 97e4b98749 [ValueTracking] use nonnull argument attribute to eliminate null checks
Enhancing value tracking's analysis of null-ness was suggested in D27855, so here's a first attempt at that.

This is part of solving:
https://llvm.org/bugs/show_bug.cgi?id=28430

Differential Revision: https://reviews.llvm.org/D28204

llvm-svn: 294897
2017-02-12 15:35:34 +00:00
Sanjay Patel 0e3ae439cf [InstCombine] add explanatory comment to test; NFC
The test was added at r290797, and a patch to enable the transform is proposed in D28204.

llvm-svn: 290798
2017-01-01 18:20:49 +00:00
Sanjay Patel 07537c2b6e [InstCombine] add test to show potential nonnull attribute propagation; NFC
This will change with the current draft of:
https://reviews.llvm.org/D28204

llvm-svn: 290797
2017-01-01 17:18:00 +00:00
Sanjay Patel 2d82aa7af7 [InstCombine] auto-generate checks; NFC
llvm-svn: 289959
2016-12-16 16:58:54 +00:00
Chen Li 0d043b52eb [InstCombineCalls] Use isKnownNonNullAt() to check nullness of passing arguments at callsite
Summary: This patch replaces isKnownNonNull() with isKnownNonNullAt() when checking nullness of passing arguments at callsite. In this way it can handle cases where the argument does not have nonnull attribute but has a dominating null check from the CFG. It also adds assertions in isKnownNonNull() and isKnownNonNullFromDominatingCondition() to make sure the value checked is pointer type (as defined in LLVM document). These assertions might trip failures in things which are not  covered under llvm/test, but fixes should be pretty obvious. 

Reviewers: reames

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12779

llvm-svn: 247587
2015-09-14 18:10:43 +00:00
Mehdi Amini 2bd08527ff Revert "[InstCombineCalls] Use isKnownNonNullAt() to check nullness of passing arguments at callsite"
This reverts commit r247356.

Breaks test/Transforms/InstCombine/pr8547.ll with:

Wrong types for attribute: byval inalloca nest noalias nocapture nonnull readnone readonly sret dereferenceable(1) dereferenceable_or_null(1)
  %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([10 x i8], [10 x i8]* @.str, i64 0, i64 0), i32 nonnull %conv2) #0
LLVM ERROR: Broken function found, compilation aborted!

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 247371
2015-09-11 01:33:48 +00:00
Chen Li a29c612ddd [InstCombineCalls] Use isKnownNonNullAt() to check nullness of passing arguments at callsite
Summary: This patch replaces isKnownNonNull() with isKnownNonNullAt() when checking nullness of passing arguments at callsite. In this way it can handle cases where the argument does not have nonnull attribute but has a dominating null check from the CFG.

Reviewers: reames

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D12779

llvm-svn: 247356
2015-09-10 23:04:49 +00:00