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| ; RUN: llc -verify-machineinstrs -mtriple=x86_64-unknown < %s | FileCheck %s --implicit-check-not="jmp.*\*" --implicit-check-not="call.*\*" --check-prefix=X64
; RUN: llc -verify-machineinstrs -mtriple=x86_64-unknown -O0 < %s | FileCheck %s --implicit-check-not="jmp.*\*" --implicit-check-not="call.*\*" --check-prefix=X64FAST
; RUN: llc -verify-machineinstrs -mtriple=i686-unknown < %s | FileCheck %s --implicit-check-not="jmp.*\*" --implicit-check-not="call.*\*" --check-prefix=X86
; RUN: llc -verify-machineinstrs -mtriple=i686-unknown -O0 < %s | FileCheck %s --implicit-check-not="jmp.*\*" --implicit-check-not="call.*\*" --check-prefix=X86FAST
declare void @bar(i32)
; Test a simple indirect call and tail call.
define void @icall_reg(void (i32)* %fp, i32 %x) #0 {
entry:
tail call void @bar(i32 %x)
tail call void %fp(i32 %x)
tail call void @bar(i32 %x)
tail call void %fp(i32 %x)
ret void
}
; X64-LABEL: icall_reg:
; X64-DAG: movq %rdi, %[[fp:[^ ]*]]
; X64-DAG: movl %esi, %[[x:[^ ]*]]
; X64: movl %esi, %edi
; X64: callq bar
; X64-DAG: movl %[[x]], %edi
; X64-DAG: movq %[[fp]], %r11
; X64: callq __llvm_retpoline_r11
; X64: movl %[[x]], %edi
; X64: callq bar
; X64-DAG: movl %[[x]], %edi
; X64-DAG: movq %[[fp]], %r11
; X64: jmp __llvm_retpoline_r11 # TAILCALL
; X64FAST-LABEL: icall_reg:
; X64FAST: callq bar
; X64FAST: callq __llvm_retpoline_r11
; X64FAST: callq bar
; X64FAST: jmp __llvm_retpoline_r11 # TAILCALL
; X86-LABEL: icall_reg:
; X86-DAG: movl 12(%esp), %[[fp:[^ ]*]]
; X86-DAG: movl 16(%esp), %[[x:[^ ]*]]
; X86: pushl %[[x]]
; X86: calll bar
; X86: movl %[[fp]], %eax
; X86: pushl %[[x]]
; X86: calll __llvm_retpoline_eax
; X86: pushl %[[x]]
; X86: calll bar
; X86: movl %[[fp]], %eax
; X86: pushl %[[x]]
; X86: calll __llvm_retpoline_eax
; X86-NOT: # TAILCALL
; X86FAST-LABEL: icall_reg:
; X86FAST: calll bar
; X86FAST: calll __llvm_retpoline_eax
; X86FAST: calll bar
; X86FAST: calll __llvm_retpoline_eax
@global_fp = external global void (i32)*
; Test an indirect call through a global variable.
define void @icall_global_fp(i32 %x, void (i32)** %fpp) #0 {
%fp1 = load void (i32)*, void (i32)** @global_fp
call void %fp1(i32 %x)
%fp2 = load void (i32)*, void (i32)** @global_fp
tail call void %fp2(i32 %x)
ret void
}
; X64-LABEL: icall_global_fp:
; X64-DAG: movl %edi, %[[x:[^ ]*]]
; X64-DAG: movq global_fp(%rip), %r11
; X64: callq __llvm_retpoline_r11
; X64-DAG: movl %[[x]], %edi
; X64-DAG: movq global_fp(%rip), %r11
; X64: jmp __llvm_retpoline_r11 # TAILCALL
; X64FAST-LABEL: icall_global_fp:
; X64FAST: movq global_fp(%rip), %r11
; X64FAST: callq __llvm_retpoline_r11
; X64FAST: movq global_fp(%rip), %r11
; X64FAST: jmp __llvm_retpoline_r11 # TAILCALL
; X86-LABEL: icall_global_fp:
; X86: movl global_fp, %eax
; X86: pushl 4(%esp)
; X86: calll __llvm_retpoline_eax
; X86: addl $4, %esp
; X86: movl global_fp, %eax
; X86: jmp __llvm_retpoline_eax # TAILCALL
; X86FAST-LABEL: icall_global_fp:
; X86FAST: calll __llvm_retpoline_eax
; X86FAST: jmp __llvm_retpoline_eax # TAILCALL
%struct.Foo = type { void (%struct.Foo*)** }
; Test an indirect call through a vtable.
define void @vcall(%struct.Foo* %obj) #0 {
%vptr_field = getelementptr %struct.Foo, %struct.Foo* %obj, i32 0, i32 0
%vptr = load void (%struct.Foo*)**, void (%struct.Foo*)*** %vptr_field
%vslot = getelementptr void(%struct.Foo*)*, void(%struct.Foo*)** %vptr, i32 1
%fp = load void(%struct.Foo*)*, void(%struct.Foo*)** %vslot
tail call void %fp(%struct.Foo* %obj)
tail call void %fp(%struct.Foo* %obj)
ret void
}
; X64-LABEL: vcall:
; X64: movq %rdi, %[[obj:[^ ]*]]
; X64: movq (%rdi), %[[vptr:[^ ]*]]
; X64: movq 8(%[[vptr]]), %[[fp:[^ ]*]]
; X64: movq %[[fp]], %r11
; X64: callq __llvm_retpoline_r11
; X64-DAG: movq %[[obj]], %rdi
; X64-DAG: movq %[[fp]], %r11
; X64: jmp __llvm_retpoline_r11 # TAILCALL
; X64FAST-LABEL: vcall:
; X64FAST: callq __llvm_retpoline_r11
; X64FAST: jmp __llvm_retpoline_r11 # TAILCALL
; X86-LABEL: vcall:
; X86: movl 8(%esp), %[[obj:[^ ]*]]
; X86: movl (%[[obj]]), %[[vptr:[^ ]*]]
; X86: movl 4(%[[vptr]]), %[[fp:[^ ]*]]
; X86: movl %[[fp]], %eax
; X86: pushl %[[obj]]
; X86: calll __llvm_retpoline_eax
; X86: addl $4, %esp
; X86: movl %[[fp]], %eax
; X86: jmp __llvm_retpoline_eax # TAILCALL
; X86FAST-LABEL: vcall:
; X86FAST: calll __llvm_retpoline_eax
; X86FAST: jmp __llvm_retpoline_eax # TAILCALL
declare void @direct_callee()
define void @direct_tail() #0 {
tail call void @direct_callee()
ret void
}
; X64-LABEL: direct_tail:
; X64: jmp direct_callee # TAILCALL
; X64FAST-LABEL: direct_tail:
; X64FAST: jmp direct_callee # TAILCALL
; X86-LABEL: direct_tail:
; X86: jmp direct_callee # TAILCALL
; X86FAST-LABEL: direct_tail:
; X86FAST: jmp direct_callee # TAILCALL
declare void @nonlazybind_callee() #2
define void @nonlazybind_caller() #0 {
call void @nonlazybind_callee()
tail call void @nonlazybind_callee()
ret void
}
; X64-LABEL: nonlazybind_caller:
; X64: movq nonlazybind_callee@GOTPCREL(%rip), %[[REG:.*]]
; X64: movq %[[REG]], %r11
; X64: callq __llvm_retpoline_r11
; X64: movq %[[REG]], %r11
; X64: jmp __llvm_retpoline_r11 # TAILCALL
; X64FAST-LABEL: nonlazybind_caller:
; X64FAST: movq nonlazybind_callee@GOTPCREL(%rip), %r11
; X64FAST: callq __llvm_retpoline_r11
; X64FAST: movq nonlazybind_callee@GOTPCREL(%rip), %r11
; X64FAST: jmp __llvm_retpoline_r11 # TAILCALL
; X86-LABEL: nonlazybind_caller:
; X86: calll nonlazybind_callee@PLT
; X86: jmp nonlazybind_callee@PLT # TAILCALL
; X86FAST-LABEL: nonlazybind_caller:
; X86FAST: calll nonlazybind_callee@PLT
; X86FAST: jmp nonlazybind_callee@PLT # TAILCALL
; Check that a switch gets lowered using a jump table when retpolines are only
; enabled for calls.
define void @switch_jumptable(i32* %ptr, i64* %sink) #0 {
; X64-LABEL: switch_jumptable:
; X64: jmpq *
; X86-LABEL: switch_jumptable:
; X86: jmpl *
entry:
br label %header
header:
%i = load volatile i32, i32* %ptr
switch i32 %i, label %bb0 [
i32 1, label %bb1
i32 2, label %bb2
i32 3, label %bb3
i32 4, label %bb4
i32 5, label %bb5
i32 6, label %bb6
i32 7, label %bb7
i32 8, label %bb8
i32 9, label %bb9
]
bb0:
store volatile i64 0, i64* %sink
br label %header
bb1:
store volatile i64 1, i64* %sink
br label %header
bb2:
store volatile i64 2, i64* %sink
br label %header
bb3:
store volatile i64 3, i64* %sink
br label %header
bb4:
store volatile i64 4, i64* %sink
br label %header
bb5:
store volatile i64 5, i64* %sink
br label %header
bb6:
store volatile i64 6, i64* %sink
br label %header
bb7:
store volatile i64 7, i64* %sink
br label %header
bb8:
store volatile i64 8, i64* %sink
br label %header
bb9:
store volatile i64 9, i64* %sink
br label %header
}
@indirectbr_preserved.targets = constant [10 x i8*] [i8* blockaddress(@indirectbr_preserved, %bb0),
i8* blockaddress(@indirectbr_preserved, %bb1),
i8* blockaddress(@indirectbr_preserved, %bb2),
i8* blockaddress(@indirectbr_preserved, %bb3),
i8* blockaddress(@indirectbr_preserved, %bb4),
i8* blockaddress(@indirectbr_preserved, %bb5),
i8* blockaddress(@indirectbr_preserved, %bb6),
i8* blockaddress(@indirectbr_preserved, %bb7),
i8* blockaddress(@indirectbr_preserved, %bb8),
i8* blockaddress(@indirectbr_preserved, %bb9)]
; Check that we preserve indirectbr when only calls are retpolined.
define void @indirectbr_preserved(i64* readonly %p, i64* %sink) #0 {
; X64-LABEL: indirectbr_preserved:
; X64: jmpq *
; X86-LABEL: indirectbr_preserved:
; X86: jmpl *
entry:
%i0 = load i64, i64* %p
%target.i0 = getelementptr [10 x i8*], [10 x i8*]* @indirectbr_preserved.targets, i64 0, i64 %i0
%target0 = load i8*, i8** %target.i0
indirectbr i8* %target0, [label %bb1, label %bb3]
bb0:
store volatile i64 0, i64* %sink
br label %latch
bb1:
store volatile i64 1, i64* %sink
br label %latch
bb2:
store volatile i64 2, i64* %sink
br label %latch
bb3:
store volatile i64 3, i64* %sink
br label %latch
bb4:
store volatile i64 4, i64* %sink
br label %latch
bb5:
store volatile i64 5, i64* %sink
br label %latch
bb6:
store volatile i64 6, i64* %sink
br label %latch
bb7:
store volatile i64 7, i64* %sink
br label %latch
bb8:
store volatile i64 8, i64* %sink
br label %latch
bb9:
store volatile i64 9, i64* %sink
br label %latch
latch:
%i.next = load i64, i64* %p
%target.i.next = getelementptr [10 x i8*], [10 x i8*]* @indirectbr_preserved.targets, i64 0, i64 %i.next
%target.next = load i8*, i8** %target.i.next
; Potentially hit a full 10 successors here so that even if we rewrite as
; a switch it will try to be lowered with a jump table.
indirectbr i8* %target.next, [label %bb0,
label %bb1,
label %bb2,
label %bb3,
label %bb4,
label %bb5,
label %bb6,
label %bb7,
label %bb8,
label %bb9]
}
@indirectbr_rewrite.targets = constant [10 x i8*] [i8* blockaddress(@indirectbr_rewrite, %bb0),
i8* blockaddress(@indirectbr_rewrite, %bb1),
i8* blockaddress(@indirectbr_rewrite, %bb2),
i8* blockaddress(@indirectbr_rewrite, %bb3),
i8* blockaddress(@indirectbr_rewrite, %bb4),
i8* blockaddress(@indirectbr_rewrite, %bb5),
i8* blockaddress(@indirectbr_rewrite, %bb6),
i8* blockaddress(@indirectbr_rewrite, %bb7),
i8* blockaddress(@indirectbr_rewrite, %bb8),
i8* blockaddress(@indirectbr_rewrite, %bb9)]
; Check that when retpolines are enabled for indirect branches the indirectbr
; instruction gets rewritten to use switch, and that in turn doesn't get lowered
; as a jump table.
define void @indirectbr_rewrite(i64* readonly %p, i64* %sink) #1 {
; X64-LABEL: indirectbr_rewrite:
; X64-NOT: jmpq
; X86-LABEL: indirectbr_rewrite:
; X86-NOT: jmpl
entry:
%i0 = load i64, i64* %p
%target.i0 = getelementptr [10 x i8*], [10 x i8*]* @indirectbr_rewrite.targets, i64 0, i64 %i0
%target0 = load i8*, i8** %target.i0
indirectbr i8* %target0, [label %bb1, label %bb3]
bb0:
store volatile i64 0, i64* %sink
br label %latch
bb1:
store volatile i64 1, i64* %sink
br label %latch
bb2:
store volatile i64 2, i64* %sink
br label %latch
bb3:
store volatile i64 3, i64* %sink
br label %latch
bb4:
store volatile i64 4, i64* %sink
br label %latch
bb5:
store volatile i64 5, i64* %sink
br label %latch
bb6:
store volatile i64 6, i64* %sink
br label %latch
bb7:
store volatile i64 7, i64* %sink
br label %latch
bb8:
store volatile i64 8, i64* %sink
br label %latch
bb9:
store volatile i64 9, i64* %sink
br label %latch
latch:
%i.next = load i64, i64* %p
%target.i.next = getelementptr [10 x i8*], [10 x i8*]* @indirectbr_rewrite.targets, i64 0, i64 %i.next
%target.next = load i8*, i8** %target.i.next
; Potentially hit a full 10 successors here so that even if we rewrite as
; a switch it will try to be lowered with a jump table.
indirectbr i8* %target.next, [label %bb0,
label %bb1,
label %bb2,
label %bb3,
label %bb4,
label %bb5,
label %bb6,
label %bb7,
label %bb8,
label %bb9]
}
; Lastly check that the necessary thunks were emitted.
;
; X64-LABEL: .section .text.__llvm_retpoline_r11,{{.*}},__llvm_retpoline_r11,comdat
; X64-NEXT: .hidden __llvm_retpoline_r11
; X64-NEXT: .weak __llvm_retpoline_r11
; X64: __llvm_retpoline_r11:
; X64-NEXT: # {{.*}} # %entry
; X64-NEXT: callq [[CALL_TARGET:.*]]
; X64-NEXT: [[CAPTURE_SPEC:.*]]: # Block address taken
; X64-NEXT: # %entry
; X64-NEXT: # =>This Inner Loop Header: Depth=1
; X64-NEXT: pause
; X64-NEXT: lfence
; X64-NEXT: jmp [[CAPTURE_SPEC]]
; X64-NEXT: .p2align 4, 0x90
; X64-NEXT: {{.*}} # Block address taken
; X64-NEXT: # %entry
; X64-NEXT: [[CALL_TARGET]]:
; X64-NEXT: movq %r11, (%rsp)
; X64-NEXT: retq
;
; X86-LABEL: .section .text.__llvm_retpoline_eax,{{.*}},__llvm_retpoline_eax,comdat
; X86-NEXT: .hidden __llvm_retpoline_eax
; X86-NEXT: .weak __llvm_retpoline_eax
; X86: __llvm_retpoline_eax:
; X86-NEXT: # {{.*}} # %entry
; X86-NEXT: calll [[CALL_TARGET:.*]]
; X86-NEXT: [[CAPTURE_SPEC:.*]]: # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: # =>This Inner Loop Header: Depth=1
; X86-NEXT: pause
; X86-NEXT: lfence
; X86-NEXT: jmp [[CAPTURE_SPEC]]
; X86-NEXT: .p2align 4, 0x90
; X86-NEXT: {{.*}} # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: [[CALL_TARGET]]:
; X86-NEXT: movl %eax, (%esp)
; X86-NEXT: retl
;
; X86-LABEL: .section .text.__llvm_retpoline_ecx,{{.*}},__llvm_retpoline_ecx,comdat
; X86-NEXT: .hidden __llvm_retpoline_ecx
; X86-NEXT: .weak __llvm_retpoline_ecx
; X86: __llvm_retpoline_ecx:
; X86-NEXT: # {{.*}} # %entry
; X86-NEXT: calll [[CALL_TARGET:.*]]
; X86-NEXT: [[CAPTURE_SPEC:.*]]: # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: # =>This Inner Loop Header: Depth=1
; X86-NEXT: pause
; X86-NEXT: lfence
; X86-NEXT: jmp [[CAPTURE_SPEC]]
; X86-NEXT: .p2align 4, 0x90
; X86-NEXT: {{.*}} # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: [[CALL_TARGET]]:
; X86-NEXT: movl %ecx, (%esp)
; X86-NEXT: retl
;
; X86-LABEL: .section .text.__llvm_retpoline_edx,{{.*}},__llvm_retpoline_edx,comdat
; X86-NEXT: .hidden __llvm_retpoline_edx
; X86-NEXT: .weak __llvm_retpoline_edx
; X86: __llvm_retpoline_edx:
; X86-NEXT: # {{.*}} # %entry
; X86-NEXT: calll [[CALL_TARGET:.*]]
; X86-NEXT: [[CAPTURE_SPEC:.*]]: # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: # =>This Inner Loop Header: Depth=1
; X86-NEXT: pause
; X86-NEXT: lfence
; X86-NEXT: jmp [[CAPTURE_SPEC]]
; X86-NEXT: .p2align 4, 0x90
; X86-NEXT: {{.*}} # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: [[CALL_TARGET]]:
; X86-NEXT: movl %edx, (%esp)
; X86-NEXT: retl
;
; X86-LABEL: .section .text.__llvm_retpoline_edi,{{.*}},__llvm_retpoline_edi,comdat
; X86-NEXT: .hidden __llvm_retpoline_edi
; X86-NEXT: .weak __llvm_retpoline_edi
; X86: __llvm_retpoline_edi:
; X86-NEXT: # {{.*}} # %entry
; X86-NEXT: calll [[CALL_TARGET:.*]]
; X86-NEXT: [[CAPTURE_SPEC:.*]]: # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: # =>This Inner Loop Header: Depth=1
; X86-NEXT: pause
; X86-NEXT: lfence
; X86-NEXT: jmp [[CAPTURE_SPEC]]
; X86-NEXT: .p2align 4, 0x90
; X86-NEXT: {{.*}} # Block address taken
; X86-NEXT: # %entry
; X86-NEXT: [[CALL_TARGET]]:
; X86-NEXT: movl %edi, (%esp)
; X86-NEXT: retl
attributes #0 = { "target-features"="+retpoline-indirect-calls" }
attributes #1 = { "target-features"="+retpoline-indirect-calls,+retpoline-indirect-branches" }
attributes #2 = { nonlazybind }
|