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| ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
; Check that assume is propagated backwards through all
; operations that are `isGuaranteedToTransferExecutionToSuccessor`
; (it should reach the load and mark it as `align 32`).
define i32 @assume_inevitable(i32* %a, i32* %b, i8* %c) {
; CHECK-LABEL: @assume_inevitable(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[M:%.*]] = alloca i64, align 8
; CHECK-NEXT: [[TMP0:%.*]] = load i32, i32* [[A:%.*]], align 32
; CHECK-NEXT: [[LOADRES:%.*]] = load i32, i32* [[B:%.*]], align 4
; CHECK-NEXT: [[LOADRES2:%.*]] = call i32 @llvm.annotation.i32(i32 [[LOADRES]], i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str1, i64 0, i64 0), i32 2)
; CHECK-NEXT: store i32 [[LOADRES2]], i32* [[A]], align 32
; CHECK-NEXT: [[DUMMY_EQ:%.*]] = icmp ugt i32 [[LOADRES]], 42
; CHECK-NEXT: tail call void @llvm.assume(i1 [[DUMMY_EQ]])
; CHECK-NEXT: [[M_I8:%.*]] = bitcast i64* [[M]] to i8*
; CHECK-NEXT: [[M_A:%.*]] = call i8* @llvm.ptr.annotation.p0i8(i8* nonnull [[M_I8]], i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str1, i64 0, i64 0), i32 2)
; CHECK-NEXT: [[M_X:%.*]] = bitcast i8* [[M_A]] to i64*
; CHECK-NEXT: [[OBJSZ:%.*]] = call i64 @llvm.objectsize.i64.p0i8(i8* [[C:%.*]], i1 false, i1 false, i1 false)
; CHECK-NEXT: store i64 [[OBJSZ]], i64* [[M_X]], align 4
; CHECK-NEXT: [[PTRINT:%.*]] = ptrtoint i32* [[A]] to i64
; CHECK-NEXT: [[MASKEDPTR:%.*]] = and i64 [[PTRINT]], 31
; CHECK-NEXT: [[MASKCOND:%.*]] = icmp eq i64 [[MASKEDPTR]], 0
; CHECK-NEXT: tail call void @llvm.assume(i1 [[MASKCOND]])
; CHECK-NEXT: ret i32 [[TMP0]]
;
entry:
%dummy = alloca i8, align 4
%m = alloca i64
%0 = load i32, i32* %a, align 4
; START perform a bunch of inevitable operations
%loadres = load i32, i32* %b
%loadres2 = call i32 @llvm.annotation.i32(i32 %loadres, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str1, i32 0, i32 0), i32 2)
store i32 %loadres2, i32* %a
%dummy_eq = icmp ugt i32 %loadres, 42
tail call void @llvm.assume(i1 %dummy_eq)
call void @llvm.lifetime.start.p0i8(i64 1, i8* %dummy)
%i = call {}* @llvm.invariant.start.p0i8(i64 1, i8* %dummy)
call void @llvm.invariant.end.p0i8({}* %i, i64 1, i8* %dummy)
call void @llvm.lifetime.end.p0i8(i64 1, i8* %dummy)
%m_i8 = bitcast i64* %m to i8*
%m_a = call i8* @llvm.ptr.annotation.p0i8(i8* %m_i8, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str1, i32 0, i32 0), i32 2)
%m_x = bitcast i8* %m_a to i64*
%objsz = call i64 @llvm.objectsize.i64.p0i8(i8* %c, i1 false)
store i64 %objsz, i64* %m_x
; END perform a bunch of inevitable operations
; AND here's the assume:
%ptrint = ptrtoint i32* %a to i64
%maskedptr = and i64 %ptrint, 31
%maskcond = icmp eq i64 %maskedptr, 0
tail call void @llvm.assume(i1 %maskcond)
ret i32 %0
}
@.str = private unnamed_addr constant [4 x i8] c"sth\00", section "llvm.metadata"
@.str1 = private unnamed_addr constant [4 x i8] c"t.c\00", section "llvm.metadata"
declare i64 @llvm.objectsize.i64.p0i8(i8*, i1)
declare i32 @llvm.annotation.i32(i32, i8*, i8*, i32)
declare i8* @llvm.ptr.annotation.p0i8(i8*, i8*, i8*, i32)
declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture)
declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture)
declare {}* @llvm.invariant.start.p0i8(i64, i8* nocapture)
declare void @llvm.invariant.end.p0i8({}*, i64, i8* nocapture)
declare void @llvm.assume(i1)
|