Heejin Ahn 4f9b839772 [WebAssembly] Make EH/SjLj vars unconditionally thread local
This makes three thread local variables (`__THREW__`, `__threwValue`,
and `__wasm_lpad_context`) unconditionally thread local. If the target
doesn't support TLS, they will be downgraded to normal variables in
`stripThreadLocals`. This makes the object not linkable with other
objects using shared memory, which is what we intend here; these
variables should be thread local when used with shared memory. This is
what we initially tried in D88262.

But D88323 changed this: It only created these variables when threads
were supported, because `__THREW__` and `__threwValue` were always
generated even if Emscripten EH/SjLj was not used, making all objects
built without threads not linkable with shared memory, which was too
restrictive. But sometimes this is not safe. If we build an object using
variables such as `__THREW__` without threads, it can be linked to other
objects using shared memory, because the original object's `__THREW__`
was not created thread local to begin with.

So this CL basically reverts D88323 with some additional improvements:
- This checks each of the functions and global variables created within
  `LowerEmscriptenEHSjLj` pass and removes it if it's not used at the
  end of the pass. So only modules using those variables will be
  affected.
- Moves `CoalesceFeaturesAndStripAtomics` and `AtomicExpand` passes
  after all other IR pasess that can create thread local variables. It
  is not sufficient to move them to the end of `addIRPasses`, because
  `__wasm_lpad_context` is created in `WasmEHPrepare`, which runs inside
  `addPassesToHandleExceptions`, which runs before `addISelPrepare`. So
  we override `addISelPrepare` and move atomic/TLS stripping and
  expanding passes there.

This also removes merges `TLS` and `NO-TLS` FileCheck lines into one
`CHECK` line, because in the bitcode level we always create them as
thread local. Also some function declarations are deleted `CHECK` lines
because they are unused.

Reviewed By: tlively, sbc100

Differential Revision: https://reviews.llvm.org/D120013
2022-02-17 16:04:18 -08:00

350 lines
16 KiB
LLVM

; RUN: opt < %s -wasm-lower-em-ehsjlj -enable-emscripten-sjlj -S | FileCheck %s -DPTR=i32
; RUN: opt < %s -wasm-lower-em-ehsjlj -enable-emscripten-sjlj -S --mattr=+atomics,+bulk-memory | FileCheck %s -DPTR=i32
; RUN: opt < %s -wasm-lower-em-ehsjlj -enable-emscripten-sjlj --mtriple=wasm64-unknown-unknown -data-layout="e-m:e-p:64:64-i64:64-n32:64-S128" -S | FileCheck %s -DPTR=i64
target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
target triple = "wasm32-unknown-unknown"
%struct.__jmp_buf_tag = type { [6 x i32], i32, [32 x i32] }
@global_var = global i32 0, align 4
@global_longjmp_ptr = global void (%struct.__jmp_buf_tag*, i32)* @longjmp, align 4
; CHECK-DAG: @__THREW__ = external thread_local global [[PTR]]
; CHECK-DAG: @__threwValue = external thread_local global i32
; CHECK-DAG: @global_longjmp_ptr = global void (%struct.__jmp_buf_tag*, i32)* bitcast (void ([[PTR]], i32)* @emscripten_longjmp to void (%struct.__jmp_buf_tag*, i32)*)
; Test a simple setjmp - longjmp sequence
define void @setjmp_longjmp() {
; CHECK-LABEL: @setjmp_longjmp
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
%arraydecay1 = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
call void @longjmp(%struct.__jmp_buf_tag* %arraydecay1, i32 1) #1
unreachable
; CHECK: entry:
; CHECK-NEXT: %[[MALLOCCALL:.*]] = tail call i8* @malloc(i32 40)
; CHECK-NEXT: %[[SETJMP_TABLE:.*]] = bitcast i8* %[[MALLOCCALL]] to i32*
; CHECK-NEXT: store i32 0, i32* %[[SETJMP_TABLE]]
; CHECK-NEXT: %[[SETJMP_TABLE_SIZE:.*]] = add i32 4, 0
; CHECK-NEXT: br label %entry.split
; CHECK: entry.split
; CHECK-NEXT: %[[BUF:.*]] = alloca [1 x %struct.__jmp_buf_tag]
; CHECK-NEXT: %[[ARRAYDECAY:.*]] = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %[[BUF]], i32 0, i32 0
; CHECK-NEXT: %[[SETJMP_TABLE1:.*]] = call i32* @saveSetjmp(%struct.__jmp_buf_tag* %[[ARRAYDECAY]], i32 1, i32* %[[SETJMP_TABLE]], i32 %[[SETJMP_TABLE_SIZE]])
; CHECK-NEXT: %[[SETJMP_TABLE_SIZE1:.*]] = call i32 @getTempRet0()
; CHECK-NEXT: br label %entry.split.split
; CHECK: entry.split.split:
; CHECK-NEXT: phi i32 [ 0, %entry.split ], [ %[[LONGJMP_RESULT:.*]], %if.end ]
; CHECK-NEXT: %[[ARRAYDECAY1:.*]] = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %[[BUF]], i32 0, i32 0
; CHECK-NEXT: %[[JMPBUF:.*]] = ptrtoint %struct.__jmp_buf_tag* %[[ARRAYDECAY1]] to [[PTR]]
; CHECK-NEXT: store [[PTR]] 0, [[PTR]]* @__THREW__
; CHECK-NEXT: call cc{{.*}} void @__invoke_void_[[PTR]]_i32(void ([[PTR]], i32)* @emscripten_longjmp, [[PTR]] %[[JMPBUF]], i32 1)
; CHECK-NEXT: %[[__THREW__VAL:.*]] = load [[PTR]], [[PTR]]* @__THREW__
; CHECK-NEXT: store [[PTR]] 0, [[PTR]]* @__THREW__
; CHECK-NEXT: %[[CMP0:.*]] = icmp ne [[PTR]] %__THREW__.val, 0
; CHECK-NEXT: %[[THREWVALUE_VAL:.*]] = load i32, i32* @__threwValue
; CHECK-NEXT: %[[CMP1:.*]] = icmp ne i32 %[[THREWVALUE_VAL]], 0
; CHECK-NEXT: %[[CMP:.*]] = and i1 %[[CMP0]], %[[CMP1]]
; CHECK-NEXT: br i1 %[[CMP]], label %if.then1, label %if.else1
; CHECK: entry.split.split.split:
; CHECK-NEXT: unreachable
; CHECK: if.then1:
; CHECK-NEXT: %[[__THREW__VAL_P:.*]] = inttoptr [[PTR]] %[[__THREW__VAL]] to [[PTR]]*
; CHECK-NEXT: %[[__THREW__VAL_P_LOADED:.*]] = load [[PTR]], [[PTR]]* %[[__THREW__VAL_P]]
; CHECK-NEXT: %[[LABEL:.*]] = call i32 @testSetjmp([[PTR]] %[[__THREW__VAL_P_LOADED]], i32* %[[SETJMP_TABLE1]], i32 %[[SETJMP_TABLE_SIZE1]])
; CHECK-NEXT: %[[CMP:.*]] = icmp eq i32 %[[LABEL]], 0
; CHECK-NEXT: br i1 %[[CMP]], label %call.em.longjmp, label %if.end2
; CHECK: if.else1:
; CHECK-NEXT: br label %if.end
; CHECK: if.end:
; CHECK-NEXT: %[[LABEL_PHI:.*]] = phi i32 [ %[[LABEL:.*]], %if.end2 ], [ -1, %if.else1 ]
; CHECK-NEXT: %[[LONGJMP_RESULT]] = call i32 @getTempRet0()
; CHECK-NEXT: switch i32 %[[LABEL_PHI]], label %entry.split.split.split [
; CHECK-NEXT: i32 1, label %entry.split.split
; CHECK-NEXT: ]
; CHECK: call.em.longjmp:
; CHECK-NEXT: %threw.phi = phi [[PTR]] [ %[[__THREW__VAL]], %if.then1 ]
; CHECK-NEXT: %threwvalue.phi = phi i32 [ %[[THREWVALUE_VAL]], %if.then1 ]
; CHECK-NEXT: %{{.*}} = bitcast i32* %[[SETJMP_TABLE1]] to i8*
; CHECK-NEXT: tail call void @free(i8* %{{.*}})
; CHECK-NEXT: call void @emscripten_longjmp([[PTR]] %threw.phi, i32 %threwvalue.phi)
; CHECK-NEXT: unreachable
; CHECK: if.end2:
; CHECK-NEXT: call void @setTempRet0(i32 %[[THREWVALUE_VAL]])
; CHECK-NEXT: br label %if.end
}
; Test a case of a function call (which is not longjmp) after a setjmp
define void @setjmp_longjmpable_call() {
; CHECK-LABEL: @setjmp_longjmpable_call
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
call void @foo()
ret void
; CHECK: entry:
; CHECK: %[[SETJMP_TABLE:.*]] = call i32* @saveSetjmp(
; CHECK: entry.split.split:
; CHECK: @__invoke_void(void ()* @foo)
; CHECK: entry.split.split.split:
; CHECK-NEXT: %[[BUF:.*]] = bitcast i32* %[[SETJMP_TABLE]] to i8*
; CHECK-NEXT: tail call void @free(i8* %[[BUF]])
; CHECK-NEXT: ret void
}
; When there are multiple longjmpable calls after setjmp. In this test we
; specifically check if 'call.em.longjmp' BB, which rethrows longjmps by calling
; emscripten_longjmp for ones that are not for this function's setjmp, is
; correctly created for multiple predecessors.
define void @setjmp_multiple_longjmpable_calls() {
; CHECK-LABEL: @setjmp_multiple_longjmpable_calls
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
call void @foo()
call void @foo()
ret void
; CHECK: call.em.longjmp:
; CHECK-NEXT: %threw.phi = phi [[PTR]] [ %__THREW__.val, %if.then1 ], [ %__THREW__.val4, %if.then15 ]
; CHECK-NEXT: %threwvalue.phi = phi i32 [ %__threwValue.val, %if.then1 ], [ %__threwValue.val8, %if.then15 ]
; CHECK-NEXT: %{{.*}} = bitcast i32* %[[SETJMP_TABLE1]] to i8*
; CHECK-NEXT: tail call void @free(i8* %{{.*}})
; CHECK-NEXT: call void @emscripten_longjmp([[PTR]] %threw.phi, i32 %threwvalue.phi)
; CHECK-NEXT: unreachable
}
; Test a case where a function has a setjmp call but no other calls that can
; longjmp. We don't need to do any transformation in this case.
define i32 @setjmp_only(i8* %ptr) {
; CHECK-LABEL: @setjmp_only
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
; free cannot longjmp
call void @free(i8* %ptr)
ret i32 %call
; CHECK: entry:
; CHECK-NOT: @malloc
; CHECK-NOT: %setjmpTable
; CHECK-NOT: @saveSetjmp
; CHECK-NOT: @testSetjmp
; The remaining setjmp call is converted to constant 0, because setjmp returns 0
; when called directly.
; CHECK: ret i32 0
}
; Test SSA validity
define void @ssa(i32 %n) {
; CHECK-LABEL: @ssa
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%cmp = icmp sgt i32 %n, 5
br i1 %cmp, label %if.then, label %if.end
; CHECK: entry:
; CHECK: %[[SETJMP_TABLE0:.*]] = bitcast i8*
; CHECK: %[[SETJMP_TABLE_SIZE0:.*]] = add i32 4, 0
if.then: ; preds = %entry
%0 = load i32, i32* @global_var, align 4
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
store i32 %0, i32* @global_var, align 4
br label %if.end
; CHECK: if.then:
; CHECK: %[[VAR0:.*]] = load i32, i32* @global_var, align 4
; CHECK: %[[SETJMP_TABLE1:.*]] = call i32* @saveSetjmp(
; CHECK-NEXT: %[[SETJMP_TABLE_SIZE1:.*]] = call i32 @getTempRet0()
; CHECK: if.then.split:
; CHECK: %[[VAR1:.*]] = phi i32 [ %[[VAR2:.*]], %if.end3 ], [ %[[VAR0]], %if.then ]
; CHECK: %[[SETJMP_TABLE_SIZE2:.*]] = phi i32 [ %[[SETJMP_TABLE_SIZE1]], %if.then ], [ %[[SETJMP_TABLE_SIZE3:.*]], %if.end3 ]
; CHECK: %[[SETJMP_TABLE2:.*]] = phi i32* [ %[[SETJMP_TABLE1]], %if.then ], [ %[[SETJMP_TABLE3:.*]], %if.end3 ]
; CHECK: store i32 %[[VAR1]], i32* @global_var, align 4
if.end: ; preds = %if.then, %entry
%arraydecay1 = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
call void @longjmp(%struct.__jmp_buf_tag* %arraydecay1, i32 5) #1
unreachable
; CHECK: if.end:
; CHECK: %[[VAR2]] = phi i32 [ %[[VAR1]], %if.then.split ], [ undef, %entry.split ]
; CHECK: %[[SETJMP_TABLE_SIZE3]] = phi i32 [ %[[SETJMP_TABLE_SIZE2]], %if.then.split ], [ %[[SETJMP_TABLE_SIZE0]], %entry.split ]
; CHECK: %[[SETJMP_TABLE3]] = phi i32* [ %[[SETJMP_TABLE2]], %if.then.split ], [ %[[SETJMP_TABLE0]], %entry.split ]
}
; Test a case when a function only calls other functions that are neither setjmp nor longjmp
define void @other_func_only() {
; CHECK-LABEL: @other_func_only
entry:
call void @foo()
ret void
; CHECK: call void @foo()
}
; Test inline asm handling
define void @inline_asm() {
; CHECK-LABEL: @inline_asm
entry:
%env = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %env, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #4
; Inline assembly should not generate __invoke wrappers.
; Doing so would fail as inline assembly cannot be passed as a function pointer.
; CHECK: call void asm sideeffect "", ""()
; CHECK-NOT: __invoke_void
call void asm sideeffect "", ""()
ret void
}
; Test that the allocsize attribute is being transformed properly
declare i8 *@allocator(i32, %struct.__jmp_buf_tag*) #3
define i8 *@allocsize() {
; CHECK-LABEL: @allocsize
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
; CHECK: call cc{{.*}} i8* @"__invoke_i8*_i32_%struct.__jmp_buf_tag*"([[ARGS:.*]]) #[[ALLOCSIZE_ATTR:[0-9]+]]
%alloc = call i8* @allocator(i32 20, %struct.__jmp_buf_tag* %arraydecay) #3
ret i8 *%alloc
}
; Test a case when a function only calls longjmp and not setjmp
@buffer = global [1 x %struct.__jmp_buf_tag] zeroinitializer, align 16
define void @longjmp_only() {
; CHECK-LABEL: @longjmp_only
entry:
; CHECK: call void @emscripten_longjmp
call void @longjmp(%struct.__jmp_buf_tag* getelementptr inbounds ([1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* @buffer, i32 0, i32 0), i32 1) #1
unreachable
}
; Tests if SSA rewrite works when a use and its def are within the same BB.
define void @ssa_rewite_in_same_bb() {
; CHECK-LABEL: @ssa_rewite_in_same_bb
entry:
call void @foo()
br label %for.cond
for.cond: ; preds = %for.inc, %entry
; CHECK: %{{.*}} = phi i32 [ %var[[VARNO:.*]], %for.inc.split ]
%0 = phi i32 [ %var, %for.inc ], [ undef, %entry ]
%var = add i32 0, 0
br label %for.inc
for.inc: ; preds = %for.cond
%call5 = call i32 @setjmp(%struct.__jmp_buf_tag* undef) #0
br label %for.cond
; CHECK: for.inc.split:
; CHECK: %var[[VARNO]] = phi i32 [ undef, %if.end ], [ %var, %for.inc ]
}
; Tests cases where longjmp function pointer is used in other ways than direct
; calls. longjmps should be replaced with
; (void(*)(jmp_buf*, int))emscripten_longjmp.
declare void @take_longjmp(void (%struct.__jmp_buf_tag*, i32)* %arg_ptr)
define void @indirect_longjmp() {
; CHECK-LABEL: @indirect_longjmp
entry:
%local_longjmp_ptr = alloca void (%struct.__jmp_buf_tag*, i32)*, align 4
%buf0 = alloca [1 x %struct.__jmp_buf_tag], align 16
%buf1 = alloca [1 x %struct.__jmp_buf_tag], align 16
; Store longjmp in a local variable, load it, and call it
store void (%struct.__jmp_buf_tag*, i32)* @longjmp, void (%struct.__jmp_buf_tag*, i32)** %local_longjmp_ptr, align 4
; CHECK: store void (%struct.__jmp_buf_tag*, i32)* bitcast (void ([[PTR]], i32)* @emscripten_longjmp to void (%struct.__jmp_buf_tag*, i32)*), void (%struct.__jmp_buf_tag*, i32)** %local_longjmp_ptr, align 4
%longjmp_from_local_ptr = load void (%struct.__jmp_buf_tag*, i32)*, void (%struct.__jmp_buf_tag*, i32)** %local_longjmp_ptr, align 4
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf0, i32 0, i32 0
call void %longjmp_from_local_ptr(%struct.__jmp_buf_tag* %arraydecay, i32 0)
; Load longjmp from a global variable and call it
%longjmp_from_global_ptr = load void (%struct.__jmp_buf_tag*, i32)*, void (%struct.__jmp_buf_tag*, i32)** @global_longjmp_ptr, align 4
%arraydecay1 = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf1, i32 0, i32 0
call void %longjmp_from_global_ptr(%struct.__jmp_buf_tag* %arraydecay1, i32 0)
; Pass longjmp as a function argument. This is a call but longjmp is not a
; callee but an argument.
call void @take_longjmp(void (%struct.__jmp_buf_tag*, i32)* @longjmp)
; CHECK: call void @take_longjmp(void (%struct.__jmp_buf_tag*, i32)* bitcast (void ([[PTR]], i32)* @emscripten_longjmp to void (%struct.__jmp_buf_tag*, i32)*))
ret void
}
; Test if _setjmp and _longjmp calls are treated in the same way as setjmp and
; longjmp
define void @_setjmp__longjmp() {
; CHECK-LABEL: @_setjmp__longjmp
; These calls should have been transformed away
; CHECK-NOT: call i32 @_setjmp
; CHECK-NOT: call void @_longjmp
entry:
%buf = alloca [1 x %struct.__jmp_buf_tag], align 16
%arraydecay = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
%call = call i32 @_setjmp(%struct.__jmp_buf_tag* %arraydecay) #0
%arraydecay1 = getelementptr inbounds [1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* %buf, i32 0, i32 0
call void @_longjmp(%struct.__jmp_buf_tag* %arraydecay1, i32 1) #1
unreachable
}
; Function Attrs: nounwind
declare void @foo() #2
; Function Attrs: returns_twice
declare i32 @setjmp(%struct.__jmp_buf_tag*) #0
declare i32 @_setjmp(%struct.__jmp_buf_tag*) #0
; Function Attrs: noreturn
declare void @longjmp(%struct.__jmp_buf_tag*, i32) #1
declare void @_longjmp(%struct.__jmp_buf_tag*, i32) #1
declare i32 @__gxx_personality_v0(...)
declare i8* @__cxa_begin_catch(i8*)
declare void @__cxa_end_catch()
declare i8* @malloc(i32)
declare void @free(i8*)
; JS glue functions and invoke wrappers declaration
; CHECK-DAG: declare i32 @getTempRet0()
; CHECK-DAG: declare void @setTempRet0(i32)
; CHECK-DAG: declare i32* @saveSetjmp(%struct.__jmp_buf_tag*, i32, i32*, i32)
; CHECK-DAG: declare i32 @testSetjmp([[PTR]], i32*, i32)
; CHECK-DAG: declare void @emscripten_longjmp([[PTR]], i32)
; CHECK-DAG: declare void @__invoke_void(void ()*)
attributes #0 = { returns_twice }
attributes #1 = { noreturn }
attributes #2 = { nounwind }
attributes #3 = { allocsize(0) }
; CHECK-DAG: attributes #{{[0-9]+}} = { nounwind "wasm-import-module"="env" "wasm-import-name"="getTempRet0" }
; CHECK-DAG: attributes #{{[0-9]+}} = { nounwind "wasm-import-module"="env" "wasm-import-name"="setTempRet0" }
; CHECK-DAG: attributes #{{[0-9]+}} = { "wasm-import-module"="env" "wasm-import-name"="__invoke_void" }
; CHECK-DAG: attributes #{{[0-9]+}} = { "wasm-import-module"="env" "wasm-import-name"="saveSetjmp" }
; CHECK-DAG: attributes #{{[0-9]+}} = { "wasm-import-module"="env" "wasm-import-name"="testSetjmp" }
; CHECK-DAG: attributes #{{[0-9]+}} = { noreturn "wasm-import-module"="env" "wasm-import-name"="emscripten_longjmp" }
; CHECK-DAG: attributes #{{[0-9]+}} = { "wasm-import-module"="env" "wasm-import-name"="__invoke_i8*_i32_%struct.__jmp_buf_tag*" }
; CHECK-DAG: attributes #[[ALLOCSIZE_ATTR]] = { allocsize(1) }
!llvm.dbg.cu = !{!2}
!llvm.module.flags = !{!0}
!0 = !{i32 2, !"Debug Info Version", i32 3}
!1 = !DIFile(filename: "lower-em-sjlj.c", directory: "test")
!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1)
!3 = distinct !DISubprogram(name: "setjmp_debug_info", unit:!2, file: !1, line: 1)
!4 = !DILocation(line:2, scope: !3)
!5 = !DILocation(line:3, scope: !3)
!6 = !DILocation(line:4, scope: !3)
!7 = !DILocation(line:5, scope: !3)
!8 = !DILocation(line:6, scope: !3)