mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-23 11:13:28 +01:00
e3bab282ea
The patch evaluates the expansion cost of exitValue in indVarSimplify pass, and only does the rewriting when the expansion cost is low or loop can be deleted with the rewriting. It provides an option "-replexitval=" to control the default aggressiveness of the exitvalue rewriting. It also fixes some missing cases in SCEVExpander::isHighCostExpansionHelper to enhance the evaluation of SCEV expansion cost. Differential Revision: http://reviews.llvm.org/D9800 llvm-svn: 238507
25 lines
830 B
LLVM
25 lines
830 B
LLVM
; RUN: opt < %s -indvars -loop-deletion -S |FileCheck %s
|
|
|
|
; Check IndVarSimplify should replace exit value even if the expansion cost
|
|
; is high because the loop can be deleted after the exit value rewrite.
|
|
;
|
|
; CHECK-LABEL: @_Z3fooPKcjj(
|
|
; CHECK: udiv
|
|
; CHECK: [[LABEL:^[a-zA-Z0-9_.]+]]:
|
|
; CHECK-NOT: br {{.*}} [[LABEL]]
|
|
|
|
define i32 @_Z3fooPKcjj(i8* nocapture readnone %s, i32 %len, i32 %c) #0 {
|
|
entry:
|
|
br label %while.cond
|
|
|
|
while.cond: ; preds = %while.cond, %entry
|
|
%klen.0 = phi i32 [ %len, %entry ], [ %sub, %while.cond ]
|
|
%cmp = icmp ugt i32 %klen.0, 11
|
|
%sub = add i32 %klen.0, -12
|
|
br i1 %cmp, label %while.cond, label %while.end
|
|
|
|
while.end: ; preds = %while.cond
|
|
%klen.0.lcssa = phi i32 [ %klen.0, %while.cond ]
|
|
ret i32 %klen.0.lcssa
|
|
}
|