6 Commits

Author SHA1 Message Date
Nadav Rotem
ea2c50c041 When merging connsecutive stores, use vectors to store the constant zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165267 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-04 22:35:15 +00:00
Nadav Rotem
c653de6c0f A DAGCombine optimization for mergeing consecutive stores to memory. The optimization
is not profitable in many cases because modern processors perform multiple stores
in parallel and merging stores prior to merging requires extra work. We handle two main cases:

1. Store of multiple consecutive constants:
  q->a = 3;
  q->4 = 5;
In this case we store a single legal wide integer.

2. Store of multiple consecutive loads:
  int a = p->a;
  int b = p->b;
  q->a = a;
  q->b = b;
In this case we load/store either ilegal vector registers or legal wide integer registers.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165125 91177308-0d34-0410-b5e6-96231b3b80d8
2012-10-03 16:11:15 +00:00
Nadav Rotem
73fab91f2c Revert r164910 because it causes failures to several phase2 builds.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164911 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-30 07:17:56 +00:00
Nadav Rotem
e5f163a3b9 A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work.  We only handle these cases:

1. Consecutive stores where the values and consecutive loads. For example:
 int a = p->a;
 int b = p->b;
 q->a = a;
 q->b = b;

2. Consecutive stores where the values are constants. Foe example:
 q->a = 4;
 q->b = 5;



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164910 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-30 06:24:14 +00:00
Duncan Sands
454627252b Speculatively revert commit 164885 (nadav) in the hope of ressurecting a pile of
buildbots.  Original commit message:

A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work.  We only handle these cases:

1. Consecutive stores where the values and consecutive loads. For example:
  int a = p->a;
  int b = p->b;
  q->a = a;
  q->b = b;

2. Consecutive stores where the values are constants. Foe example:
  q->a = 4;
  q->b = 5;



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164890 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-29 10:25:35 +00:00
Nadav Rotem
72f7b0811e A DAGCombine optimization for merging consecutive stores. This optimization is not profitable in many cases
because moden processos can store multiple values in parallel, and preparing the consecutive store requires
some work.  We only handle these cases:

1. Consecutive stores where the values and consecutive loads. For example:
  int a = p->a;
  int b = p->b;
  q->a = a;
  q->b = b;

2. Consecutive stores where the values are constants. Foe example:
  q->a = 4;
  q->b = 5;



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164885 91177308-0d34-0410-b5e6-96231b3b80d8
2012-09-29 06:33:25 +00:00