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llvm-project/llvm/test/Transforms/Inline/vector-bonus.ll

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[inliner] Fix the early-exit of the inline cost analysis to correctly model the dense vector instruction bonuses. Previously, this code really didn't effectively compute the density of inlined vector instructions and apply the intended inliner bonus. It would try to compute it repeatedly while analyzing the function and didn't handle the case where future vector instructions would tip the scales back towards the bonus. Instead, speculatively apply all possible bonuses to the threshold initially. Once we *know* that a certain bonus can not be applied, subtract it. This should delay early bailout enough to get much more consistent results without actually causing us to analyze huge swaths of code. I expect some (hopefully mild) compile time hit here, and some swings in performance, but this was definitely the intended behavior of these bonuses. This also dramatically simplifies the computation of the bonuses to not interact with each other in confusing ways. The previous code didn't do a good job of this and the values for bonuses may be surprising but are at least now clearly written in the code. Finally, fix code to be in line with comments and use zero as the bailout condition. Patch by Easwaran Raman, with some comment tweaks by me to try and further clarify what is going on with this code. http://reviews.llvm.org/D8267 llvm-svn: 238276
2015-05-27 10:49:05 +08:00
; RUN: opt < %s -inline -inline-threshold=35 -S | FileCheck %s
[PM] Turn on the new PM's inliner in addition to the current one for most of the inliner test cases. The inliner involves a bunch of interesting code and tends to be where most of the issues I've seen experimenting with the new PM lie. All of these test cases pass, but I'd like to keep some more thorough coverage here so doing a fairly blanket enabling. There are a handful of interesting tests I've not enabled yet because they're focused on the always inliner, or on functionality that doesn't (yet) exist in the inliner. llvm-svn: 290592
2016-12-27 15:18:43 +08:00
; RUN: opt < %s -passes='cgscc(inline)' -inline-threshold=35 -S | FileCheck %s
[inliner] Fix the early-exit of the inline cost analysis to correctly model the dense vector instruction bonuses. Previously, this code really didn't effectively compute the density of inlined vector instructions and apply the intended inliner bonus. It would try to compute it repeatedly while analyzing the function and didn't handle the case where future vector instructions would tip the scales back towards the bonus. Instead, speculatively apply all possible bonuses to the threshold initially. Once we *know* that a certain bonus can not be applied, subtract it. This should delay early bailout enough to get much more consistent results without actually causing us to analyze huge swaths of code. I expect some (hopefully mild) compile time hit here, and some swings in performance, but this was definitely the intended behavior of these bonuses. This also dramatically simplifies the computation of the bonuses to not interact with each other in confusing ways. The previous code didn't do a good job of this and the values for bonuses may be surprising but are at least now clearly written in the code. Finally, fix code to be in line with comments and use zero as the bailout condition. Patch by Easwaran Raman, with some comment tweaks by me to try and further clarify what is going on with this code. http://reviews.llvm.org/D8267 llvm-svn: 238276
2015-05-27 10:49:05 +08:00
define i32 @bar(<4 x i32> %v, i32 %i) #0 {
entry:
%cmp = icmp sgt i32 %i, 4
br i1 %cmp, label %if.then, label %if.else
if.then: ; preds = %entry
%mul1 = mul nsw i32 %i, %i
br label %return
if.else: ; preds = %entry
%add1 = add nsw i32 %i, %i
%add2 = add nsw i32 %i, %i
%add3 = add nsw i32 %i, %i
%add4 = add nsw i32 %i, %i
%add5 = add nsw i32 %i, %i
%add6 = add nsw i32 %i, %i
%vecext = extractelement <4 x i32> %v, i32 0
%vecext7 = extractelement <4 x i32> %v, i32 1
%add7 = add nsw i32 %vecext, %vecext7
br label %return
return: ; preds = %if.else, %if.then
%retval.0 = phi i32 [ %mul1, %if.then ], [ %add7, %if.else ]
ret i32 %retval.0
}
define i32 @foo(<4 x i32> %v, i32 %a) #1 {
; CHECK-LABEL: @foo(
; CHECK-NOT: call i32 @bar
; CHECK: ret
entry:
%call = call i32 @bar(<4 x i32> %v, i32 %a)
ret i32 %call
}