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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -passes=instcombine,simplifycfg < %s 2>&1 | FileCheck %s
declare void @llvm.assume(i1 noundef)
define void @f1(i8* %a) {
; CHECK-LABEL: @f1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[PTR:%.*]] = getelementptr inbounds i8, i8* [[A:%.*]], i64 4
; CHECK-NEXT: [[TMP0:%.*]] = ptrtoint i8* [[PTR]] to i64
; CHECK-NEXT: [[TMP1:%.*]] = and i64 [[TMP0]], 3
; CHECK-NEXT: [[TMP2:%.*]] = icmp eq i64 [[TMP1]], 0
; CHECK-NEXT: br i1 [[TMP2]], label [[IF_THEN:%.*]], label [[IF_END:%.*]]
; CHECK: if.then:
; CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* [[PTR]], i64 4) ]
; CHECK-NEXT: [[TMP3:%.*]] = bitcast i8* [[PTR]] to i32*
; CHECK-NEXT: store i32 4, i32* [[TMP3]], align 4
; CHECK-NEXT: br label [[IF_END]]
; CHECK: if.end:
; CHECK-NEXT: ret void
;
entry:
%ptr = getelementptr inbounds i8, i8* %a, i64 4
%0 = ptrtoint i8* %ptr to i64
%1 = and i64 %0, 3
%2 = icmp eq i64 %1, 0
br i1 %2, label %if.then, label %if.end
if.then: ; preds = %entry
call void @llvm.assume(i1 true) [ "align"(i8* %ptr, i64 4) ]
%3 = ptrtoint i8* %ptr to i64
%4 = and i64 %3, 3
%5 = icmp eq i64 %4, 0
br i1 %5, label %if.then1, label %if.else1
if.then1: ; preds = %if.then
%6 = bitcast i8* %ptr to i32*
store i32 4, i32* %6, align 4
br label %if.end
if.else1: ; preds = %if.then
store i8 1, i8* %ptr, align 1
br label %if.end
if.end: ; preds = %if.then1, %if.else1, %entry
ret void
}
; TODO: We could fold away the branch "br i1 %3, ..." by either using a GEP or make getKnowledgeValidInContext aware the alignment bundle offset, and the improvement of value tracking of GEP.
define void @f2(i8* %a) {
; CHECK-LABEL: @f2(
; CHECK-NEXT: entry:
; CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* [[A:%.*]], i64 32, i32 24) ]
; CHECK-NEXT: [[TMP0:%.*]] = getelementptr inbounds i8, i8* [[A]], i64 8
; CHECK-NEXT: [[TMP1:%.*]] = ptrtoint i8* [[TMP0]] to i64
; CHECK-NEXT: [[TMP2:%.*]] = and i64 [[TMP1]], 8
; CHECK-NEXT: [[TMP3:%.*]] = icmp eq i64 [[TMP2]], 0
; CHECK-NEXT: br i1 [[TMP3]], label [[IF_THEN:%.*]], label [[IF_ELSE:%.*]]
; CHECK: if.then:
; CHECK-NEXT: [[TMP4:%.*]] = bitcast i8* [[TMP0]] to i64*
; CHECK-NEXT: store i64 16, i64* [[TMP4]], align 8
; CHECK-NEXT: br label [[IF_END:%.*]]
; CHECK: if.else:
; CHECK-NEXT: store i8 1, i8* [[TMP0]], align 8
; CHECK-NEXT: br label [[IF_END]]
; CHECK: if.end:
; CHECK-NEXT: ret void
;
entry:
call void @llvm.assume(i1 true) [ "align"(i8* %a, i64 32, i32 24) ]
%0 = getelementptr inbounds i8, i8* %a, i64 8
%1 = ptrtoint i8* %0 to i64
%2 = and i64 %1, 15
%3 = icmp eq i64 %2, 0
br i1 %3, label %if.then, label %if.else
if.then: ; preds = %entry
%4 = bitcast i8* %0 to i64*
store i64 16, i64* %4, align 4
br label %if.end
if.else: ; preds = %entry
store i8 1, i8* %0, align 1
br label %if.end
if.end: ; preds = %if.else, %if.then
ret void
}
define void @f3(i64 %a, i8* %b) {
; CHECK-LABEL: @f3(
; CHECK-NEXT: [[C:%.*]] = ptrtoint i8* [[B:%.*]] to i64
; CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* [[B]], i64 4294967296) ]
; CHECK-NEXT: [[D:%.*]] = add i64 [[C]], [[A:%.*]]
; CHECK-NEXT: call void @g(i64 [[D]])
; CHECK-NEXT: ret void
;
%c = ptrtoint i8* %b to i64
call void @llvm.assume(i1 true) [ "align"(i8* %b, i64 4294967296) ]
%d = add i64 %a, %c
call void @g(i64 %d)
ret void
}
declare void @g(i64)
define i8 @assume_align_zero(i8* %p) {
; CHECK-LABEL: @assume_align_zero(
; CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* [[P:%.*]], i64 0) ]
; CHECK-NEXT: [[V:%.*]] = load i8, i8* [[P]], align 1
; CHECK-NEXT: ret i8 [[V]]
;
call void @llvm.assume(i1 true) [ "align"(i8* %p, i64 0) ]
%v = load i8, i8* %p
ret i8 %v
}
define i8 @assume_align_non_pow2(i8* %p) {
; CHECK-LABEL: @assume_align_non_pow2(
; CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(i8* [[P:%.*]], i64 123) ]
; CHECK-NEXT: [[V:%.*]] = load i8, i8* [[P]], align 1
; CHECK-NEXT: ret i8 [[V]]
;
call void @llvm.assume(i1 true) [ "align"(i8* %p, i64 123) ]
%v = load i8, i8* %p
ret i8 %v
}
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