Commit Graph

7 Commits

Author SHA1 Message Date
Hongbin Zheng 4fe342cb75 [Polly] Generate more 'canonical' induction variable
Today Polly generates induction variable in this way:

polly.indvar = phi 0, polly.indvar.next
...
polly.indvar.next = polly.indvar + stide
polly.loop_cond = predicate polly.indvar, (UB - stride)

Instead of:

polly.indvar = phi 0, polly.indvar.next
...
polly.indvar.next = polly.indvar + stide
polly.loop_cond = predicate polly.indvar.next, UB

The way Polly generate induction variable cause some problem in the indvar simplify pass.
This patch make polly generate the later form, by assuming the induction variable never overflow

Differential Revision: https://reviews.llvm.org/D33089

llvm-svn: 302866
2017-05-12 02:17:15 +00:00
Tobias Grosser 212469e0ed tests: make test cases more robust using regexp
llvm-svn: 276262
2016-07-21 11:48:31 +00:00
Tobias Grosser 903eefd1f2 tests: fix order of memory accesses to ensure import succeeds
It seems the order in which we generated memory accesses changed such that
the import of these updated memory accesses failed for the 'loop3' statement
in this test case. Unfortunately, the existing CHECK lines were not strict
enough to catch this. Hence, besides fixing the order of the memory access
lines we also ensure that the memory access changes are both clearly visibly
and well checked.

llvm-svn: 276247
2016-07-21 07:12:17 +00:00
Tobias Grosser 3717aa5ddb This reverts recent expression type changes
The recent expression type changes still need more discussion, which will happen
on phabricator or on the mailing list. The precise list of commits reverted are:

- "Refactor division generation code"
- "[NFC] Generate runtime checks after the SCoP"
- "[FIX] Determine insertion point during SCEV expansion"
- "Look through IntToPtr & PtrToInt instructions"
- "Use minimal types for generated expressions"
- "Temporarily promote values to i64 again"
- "[NFC] Avoid unnecessary comparison for min/max expressions"
- "[Polly] Fix -Wunused-variable warnings (NFC)"
- "[NFC] Simplify min/max expression generation"
- "Simplify the type adjustment in the IslExprBuilder"

Some of them are just reverted as we would otherwise get conflicts. I will try
to re-commit them if possible.

llvm-svn: 272483
2016-06-11 19:17:15 +00:00
Johannes Doerfert 0767a511ba Use minimal types for generated expressions
We now use the minimal necessary bit width for the generated code. If
  operations might overflow (add/sub/mul) we will try to adjust the types in
  order to ensure a non-wrapping computation. If the type adjustment is not
  possible, thus the necessary type is bigger than the type value of
  --polly-max-expr-bit-width, we will use assumptions to verify the computation
  will not wrap. However, for run-time checks we cannot build assumptions but
  instead utilize overflow tracking intrinsics.

llvm-svn: 271878
2016-06-06 09:57:41 +00:00
Michael Kruse 2e02d560aa Follow uses to create value MemoryAccesses
The previously implemented approach is to follow value definitions and
create write accesses ("push defs") while searching for uses. This
requires the same relatively validity- and requirement conditions to be
replicated at multiple locations (PHI instructions, other instructions,
uses by PHIs).

We replace this by iterating over the uses in a SCoP ("pull in
requirements"), and add writes only when at least one read has been
added. It turns out to be simpler code because each use is only iterated
over once and writes are added for the first access that reads it. We
need another iteration to identify escaping values (uses not in the
SCoP), which also makes the difference between such accesses more
obvious. As a side-effect, the order of scalar MemoryAccess can change.

Differential Revision: http://reviews.llvm.org/D15706

llvm-svn: 259987
2016-02-06 09:19:40 +00:00
Tobias Grosser 0921477248 ScopInfo: Look up first (and only) array access
When rewriting the access functions of load/store statements, we are only
interested in the actual array memory location. The current code just took
the very first memory access, which could be a scalar or an array access. As
a result, we failed to update access functions even though this was requested
via .jscop.

llvm-svn: 255713
2015-12-15 23:49:53 +00:00