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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes='require<phi-values>,gvn' -S < %s | FileCheck %s
declare noalias ptr @malloc(i64)
; Detecting that %s is fully redundant should let us detect that %w is partially
; redundant.
define void @fn1(ptr noalias %start, ptr %width, i32 %h) {
; CHECK-LABEL: @fn1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[CALL:%.*]] = tail call noalias ptr @malloc(i64 1024)
; CHECK-NEXT: store ptr [[CALL]], ptr [[START:%.*]], align 8
; CHECK-NEXT: br label [[PREHEADER:%.*]]
; CHECK: preheader:
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 1, [[H:%.*]]
; CHECK-NEXT: br i1 [[CMP]], label [[PREHEADER_BODY_CRIT_EDGE:%.*]], label [[EXIT:%.*]]
; CHECK: preheader.body_crit_edge:
; CHECK-NEXT: [[W_PRE:%.*]] = load i32, ptr [[WIDTH:%.*]], align 8
; CHECK-NEXT: br label [[BODY:%.*]]
; CHECK: body:
; CHECK-NEXT: [[J:%.*]] = phi i32 [ 0, [[PREHEADER_BODY_CRIT_EDGE]] ], [ [[J_NEXT:%.*]], [[BODY]] ]
; CHECK-NEXT: store i32 0, ptr [[CALL]], align 4
; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i32 [[J]], 1
; CHECK-NEXT: [[CMP3:%.*]] = icmp slt i32 [[J_NEXT]], [[W_PRE]]
; CHECK-NEXT: br i1 [[CMP3]], label [[BODY]], label [[PREHEADER]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
%call = tail call noalias ptr @malloc(i64 1024)
store ptr %call, ptr %start, align 8
br label %preheader
preheader:
%cmp = icmp slt i32 1, %h
br i1 %cmp, label %body, label %exit
body:
%j = phi i32 [ 0, %preheader ], [ %j.next, %body ]
%s = load ptr, ptr %start, align 8
store i32 0, ptr %s, align 4
%j.next = add nuw nsw i32 %j, 1
%w = load i32, ptr %width, align 8
%cmp3 = icmp slt i32 %j.next, %w
br i1 %cmp3, label %body, label %preheader
exit:
ret void
}
; %s is fully redundant but has more than one available value. Detecting that
; %w is partially redundant requires alias analysis that can analyze those
; values.
define void @fn2(ptr noalias %start, ptr %width, i32 %h, i32 %arg) {
; CHECK-LABEL: @fn2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[CALL:%.*]] = tail call noalias ptr @malloc(i64 1024)
; CHECK-NEXT: [[CMP1:%.*]] = icmp slt i32 [[ARG:%.*]], 0
; CHECK-NEXT: br i1 [[CMP1]], label [[IF:%.*]], label [[ELSE:%.*]]
; CHECK: if:
; CHECK-NEXT: store ptr [[CALL]], ptr [[START:%.*]], align 8
; CHECK-NEXT: br label [[PREHEADER:%.*]]
; CHECK: else:
; CHECK-NEXT: [[GEP:%.*]] = getelementptr inbounds i32, ptr [[CALL]], i32 [[ARG]]
; CHECK-NEXT: store ptr [[GEP]], ptr [[START]], align 8
; CHECK-NEXT: br label [[PREHEADER]]
; CHECK: preheader:
; CHECK-NEXT: [[S:%.*]] = phi ptr [ [[S]], [[BODY:%.*]] ], [ [[GEP]], [[ELSE]] ], [ [[CALL]], [[IF]] ]
; CHECK-NEXT: [[CMP:%.*]] = icmp slt i32 1, [[H:%.*]]
; CHECK-NEXT: br i1 [[CMP]], label [[PREHEADER_BODY_CRIT_EDGE:%.*]], label [[EXIT:%.*]]
; CHECK: preheader.body_crit_edge:
; CHECK-NEXT: [[W_PRE:%.*]] = load i32, ptr [[WIDTH:%.*]], align 8
; CHECK-NEXT: br label [[BODY]]
; CHECK: body:
; CHECK-NEXT: [[J:%.*]] = phi i32 [ 0, [[PREHEADER_BODY_CRIT_EDGE]] ], [ [[J_NEXT:%.*]], [[BODY]] ]
; CHECK-NEXT: store i32 0, ptr [[S]], align 4
; CHECK-NEXT: [[J_NEXT]] = add nuw nsw i32 [[J]], 1
; CHECK-NEXT: [[CMP3:%.*]] = icmp slt i32 [[J_NEXT]], [[W_PRE]]
; CHECK-NEXT: br i1 [[CMP3]], label [[BODY]], label [[PREHEADER]]
; CHECK: exit:
; CHECK-NEXT: ret void
;
entry:
%call = tail call noalias ptr @malloc(i64 1024)
%cmp1 = icmp slt i32 %arg, 0
br i1 %cmp1, label %if, label %else
if:
store ptr %call, ptr %start, align 8
br label %preheader
else:
%gep = getelementptr inbounds i32, ptr %call, i32 %arg
store ptr %gep, ptr %start, align 8
br label %preheader
preheader:
%cmp = icmp slt i32 1, %h
br i1 %cmp, label %body, label %exit
body:
%j = phi i32 [ 0, %preheader ], [ %j.next, %body ]
%s = load ptr, ptr %start, align 8
store i32 0, ptr %s, align 4
%j.next = add nuw nsw i32 %j, 1
%w = load i32, ptr %width, align 8
%cmp3 = icmp slt i32 %j.next, %w
br i1 %cmp3, label %body, label %preheader
exit:
ret void
}
|
