llvm-project/llvm/test/Transforms/Inline/recursive.ll

74 lines
2.0 KiB
LLVM

; Inlining in the presence of recursion presents special challenges that we
; test here.
;
; RUN: opt -inline -S < %s | FileCheck %s
; RUN: opt -passes='cgscc(inline)' -S < %s | FileCheck %s
define i32 @large_stack_callee(i32 %param) {
; CHECK-LABEL: define i32 @large_stack_callee(
entry:
%yyy = alloca [100000 x i8]
%r = bitcast [100000 x i8]* %yyy to i8*
call void @bar(i8* %r)
ret i32 4
}
; Test a recursive function which calls another function with a large stack. In
; addition to not inlining the recursive call, we should also not inline the
; large stack allocation into a potentially recursive frame.
define i32 @large_stack_recursive_caller(i32 %param) {
; CHECK-LABEL: define i32 @large_stack_recursive_caller(
entry:
; CHECK-NEXT: entry:
; CHECK-NOT: alloca
%t = call i32 @foo(i32 %param)
%cmp = icmp eq i32 %t, -1
br i1 %cmp, label %exit, label %cont
cont:
%r = call i32 @large_stack_recursive_caller(i32 %t)
; CHECK: call i32 @large_stack_recursive_caller
%f = call i32 @large_stack_callee(i32 %r)
; CHECK: call i32 @large_stack_callee
br label %exit
exit:
ret i32 4
}
declare void @bar(i8* %in)
declare i32 @foo(i32 %param)
; Check that when inlining a non-recursive path into a function's own body that
; we get the re-mapping of instructions correct.
define i32 @test_recursive_inlining_remapping(i1 %init, i8* %addr) {
; CHECK-LABEL: define i32 @test_recursive_inlining_remapping(
bb:
%n = alloca i32
br i1 %init, label %store, label %load
; CHECK-NOT: alloca
;
; CHECK: %[[N:.*]] = alloca i32
; CHECK-NEXT: br i1 %init,
store:
store i32 0, i32* %n
%cast = bitcast i32* %n to i8*
%v = call i32 @test_recursive_inlining_remapping(i1 false, i8* %cast)
ret i32 %v
; CHECK-NOT: call
;
; CHECK: store i32 0, i32* %[[N]]
; CHECK-NEXT: %[[CAST:.*]] = bitcast i32* %[[N]] to i8*
; CHECK-NEXT: %[[INLINED_LOAD:.*]] = load i32, i32* %[[N]]
; CHECK-NEXT: ret i32 %[[INLINED_LOAD]]
;
; CHECK-NOT: call
load:
%castback = bitcast i8* %addr to i32*
%n.load = load i32, i32* %castback
ret i32 %n.load
}