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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -hoist-common-insts=1 -S < %s | FileCheck %s --check-prefix=HOIST
; RUN: opt -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -hoist-common-insts=0 -S < %s | FileCheck %s --check-prefix=NOHOIST
; RUN: opt -passes=simplifycfg -simplifycfg-require-and-preserve-domtree=1 -S < %s | FileCheck %s --check-prefix=NOHOIST
; This example is produced from a very basic C code:
;
; void f0();
; void f1();
; void f2();
;
; void loop(int width) {
; if(width < 1)
; return;
; for(int i = 0; i < width - 1;+i) {
; f0();
; f1();
; }
; f0();
; f2();
; }
; We have a choice here. We can either
; * hoist the f0() call into loop header,
; * which potentially makes loop rotation unprofitable since loop header might
; have grown above certain threshold, and such unrotated loops will be
; ignored by LoopVectorizer, preventing vectorization
; * or loop rotation will succeed, resulting in some weird PHIs that will also
; harm vectorization
; * or not hoist f0() call before performing loop rotation,
; at the cost of potential code bloat and/or potentially successfully rotating
; the loops, vectorizing them at the cost of compile time.
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
declare i1 @gen1()
declare void @f0()
declare void @f1()
declare void @f2()
declare void @llvm.lifetime.start.p0(i64 immarg, ptr nocapture)
declare void @llvm.lifetime.end.p0(i64 immarg, ptr nocapture)
define void @_Z4loopi(i1 %cmp) {
; HOIST-LABEL: @_Z4loopi(
; HOIST-NEXT: entry:
; HOIST-NEXT: br i1 [[CMP:%.*]], label [[RETURN:%.*]], label [[FOR_COND:%.*]]
; HOIST: for.cond:
; HOIST-NEXT: [[CMP1:%.*]] = call i1 @gen1()
; HOIST-NEXT: call void @f0()
; HOIST-NEXT: br i1 [[CMP1]], label [[FOR_BODY:%.*]], label [[FOR_END:%.*]]
; HOIST: for.body:
; HOIST-NEXT: call void @f1()
; HOIST-NEXT: br label [[FOR_COND]]
; HOIST: for.end:
; HOIST-NEXT: call void @f2()
; HOIST-NEXT: br label [[RETURN]]
; HOIST: return:
; HOIST-NEXT: ret void
;
; NOHOIST-LABEL: @_Z4loopi(
; NOHOIST-NEXT: entry:
; NOHOIST-NEXT: br i1 [[CMP:%.*]], label [[RETURN:%.*]], label [[FOR_COND:%.*]]
; NOHOIST: for.cond:
; NOHOIST-NEXT: [[CMP1:%.*]] = call i1 @gen1()
; NOHOIST-NEXT: br i1 [[CMP1]], label [[FOR_BODY:%.*]], label [[FOR_END:%.*]]
; NOHOIST: for.body:
; NOHOIST-NEXT: call void @f0()
; NOHOIST-NEXT: call void @f1()
; NOHOIST-NEXT: br label [[FOR_COND]]
; NOHOIST: for.end:
; NOHOIST-NEXT: call void @f0()
; NOHOIST-NEXT: call void @f2()
; NOHOIST-NEXT: br label [[RETURN]]
; NOHOIST: return:
; NOHOIST-NEXT: ret void
;
entry:
br i1 %cmp, label %if.then, label %if.end
if.then:
br label %return
if.end:
br label %for.cond
for.cond:
%cmp1 = call i1 @gen1()
br i1 %cmp1, label %for.body, label %for.cond.cleanup
for.cond.cleanup:
br label %for.end
for.body:
call void @f0()
call void @f1()
br label %for.inc
for.inc:
br label %for.cond
for.end:
call void @f0()
call void @f2()
br label %return
return:
ret void
}
; A example where only the branch instructions from %if.then2 and %if.end3 need
; to be hoisted, which effectively replaces the original branch in %if.end and
; only requires selects for PHIs in the successor.
define float @clamp_float_value(float %value, float %minimum_value, float %maximum_value) {
; HOIST-LABEL: @clamp_float_value(
; HOIST-NEXT: entry:
; HOIST-NEXT: [[CMP:%.*]] = fcmp ogt float [[VALUE:%.*]], [[MAXIMUM_VALUE:%.*]]
; HOIST-NEXT: [[CMP1:%.*]] = fcmp olt float [[VALUE]], [[MINIMUM_VALUE:%.*]]
; HOIST-NEXT: [[MINIMUM_VALUE_VALUE:%.*]] = select i1 [[CMP1]], float [[MINIMUM_VALUE]], float [[VALUE]]
; HOIST-NEXT: [[RETVAL_0:%.*]] = select i1 [[CMP]], float [[MAXIMUM_VALUE]], float [[MINIMUM_VALUE_VALUE]]
; HOIST-NEXT: ret float [[RETVAL_0]]
;
; NOHOIST-LABEL: @clamp_float_value(
; NOHOIST-NEXT: entry:
; NOHOIST-NEXT: [[CMP:%.*]] = fcmp ogt float [[VALUE:%.*]], [[MAXIMUM_VALUE:%.*]]
; NOHOIST-NEXT: [[CMP1:%.*]] = fcmp olt float [[VALUE]], [[MINIMUM_VALUE:%.*]]
; NOHOIST-NEXT: [[MINIMUM_VALUE_VALUE:%.*]] = select i1 [[CMP1]], float [[MINIMUM_VALUE]], float [[VALUE]]
; NOHOIST-NEXT: [[RETVAL_0:%.*]] = select i1 [[CMP]], float [[MAXIMUM_VALUE]], float [[MINIMUM_VALUE_VALUE]]
; NOHOIST-NEXT: ret float [[RETVAL_0]]
;
entry:
%cmp = fcmp ogt float %value, %maximum_value
br i1 %cmp, label %if.then, label %if.end
if.then: ; preds = %entry
br label %return
if.end: ; preds = %entry
%cmp1 = fcmp olt float %value, %minimum_value
br i1 %cmp1, label %if.then2, label %if.end3
if.then2: ; preds = %if.end
br label %return
if.end3: ; preds = %if.end
br label %return
return: ; preds = %if.end3, %if.then2, %if.then
%retval.0 = phi float [ %maximum_value, %if.then ], [ %minimum_value, %if.then2 ], [ %value, %if.end3 ]
ret float %retval.0
}
|
