diff options
| author | James Molloy <james.molloy@arm.com> | 2015-09-02 10:15:05 +0000 |
|---|---|---|
| committer | James Molloy <james.molloy@arm.com> | 2015-09-02 10:15:05 +0000 |
| commit | a860a2216a405f3d8b58139e4a663b1ba96683f6 (patch) | |
| tree | f3a844a748ea571c414fb1b5778daad7c20307f8 /llvm/test/Transforms/LoopVectorize | |
| parent | c07701b017cc729a268f28f1e50fae32d331b615 (diff) | |
| download | bcm5719-llvm-a860a2216a405f3d8b58139e4a663b1ba96683f6.tar.gz bcm5719-llvm-a860a2216a405f3d8b58139e4a663b1ba96683f6.zip | |
[LV] Never widen an induction variable.
There's no need to widen canonical induction variables. It's just as efficient to create a *new*, wide, induction variable.
Consider, if we widen an indvar, then we'll have to truncate it before its uses anyway (1 trunc). If we create a new indvar instead, we'll have to truncate that instead (1 trunc) [besides which IndVars should go and clean up our mess after us anyway on principle].
This lets us remove a ton of special-casing code.
llvm-svn: 246631
Diffstat (limited to 'llvm/test/Transforms/LoopVectorize')
| -rw-r--r-- | llvm/test/Transforms/LoopVectorize/ptr-induction.ll | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/llvm/test/Transforms/LoopVectorize/ptr-induction.ll b/llvm/test/Transforms/LoopVectorize/ptr-induction.ll new file mode 100644 index 00000000000..df26efb34b5 --- /dev/null +++ b/llvm/test/Transforms/LoopVectorize/ptr-induction.ll @@ -0,0 +1,34 @@ +; RUN: opt < %s -loop-vectorize -force-vector-width=4 -S | FileCheck %s + +target datalayout = "e-m:e-i64:64-i128:128-n32:64-S128" + +; This testcase causes SCEV to return a pointer-typed exit value. + +; CHECK: @f +; Expect that the pointer indvar has been converted into an integer indvar. +; CHECK: %index.next = add i64 %index, 4 +define i32 @f(i32* readonly %a, i32* readnone %b) #0 { +entry: + %cmp.6 = icmp ult i32* %a, %b + br i1 %cmp.6, label %while.body.preheader, label %while.end + +while.body.preheader: ; preds = %entry + br label %while.body + +while.body: ; preds = %while.body.preheader, %while.body + %a.pn = phi i32* [ %incdec.ptr8, %while.body ], [ %a, %while.body.preheader ] + %acc.07 = phi i32 [ %add, %while.body ], [ 0, %while.body.preheader ] + %incdec.ptr8 = getelementptr inbounds i32, i32* %a.pn, i64 1 + %0 = load i32, i32* %incdec.ptr8, align 1 + %add = add nuw nsw i32 %0, %acc.07 + %exitcond = icmp eq i32* %incdec.ptr8, %b + br i1 %exitcond, label %while.cond.while.end_crit_edge, label %while.body + +while.cond.while.end_crit_edge: ; preds = %while.body + %add.lcssa = phi i32 [ %add, %while.body ] + br label %while.end + +while.end: ; preds = %while.cond.while.end_crit_edge, %entry + %acc.0.lcssa = phi i32 [ %add.lcssa, %while.cond.while.end_crit_edge ], [ 0, %entry ] + ret i32 %acc.0.lcssa +}
\ No newline at end of file |
