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|
; RUN: llc -mattr=harden-sls-retbr,harden-sls-blr -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s --check-prefixes=CHECK,HARDEN,HARDEN-COMDAT,ISBDSB,ISBDSBDAGISEL
; RUN: llc -mattr=harden-sls-retbr,harden-sls-blr,harden-sls-nocomdat -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s --check-prefixes=CHECK,HARDEN,HARDEN-COMDAT-OFF,ISBDSB,ISBDSBDAGISEL
; RUN: llc -mattr=harden-sls-retbr,harden-sls-blr -mattr=+sb -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s --check-prefixes=CHECK,HARDEN,SB,SBDAGISEL
; RUN: llc -global-isel -global-isel-abort=0 -mattr=harden-sls-retbr,harden-sls-blr -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s --check-prefixes=CHECK,HARDEN,HARDEN-COMDAT,ISBDSB
; RUN: llc -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s --check-prefixes=CHECK,NOHARDEN
; RUN: llc -global-isel -global-isel-abort=0 -mattr=harden-sls-retbr,harden-sls-blr,harden-sls-nocomdat -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s --check-prefixes=CHECK,HARDEN,HARDEN-COMDAT-OFF,ISBDSB
; RUN: llc -global-isel -global-isel-abort=0 -mattr=harden-sls-retbr,harden-sls-blr -mattr=+sb -verify-machineinstrs -mtriple=aarch64-none-linux-gnu < %s | FileCheck %s --check-prefixes=CHECK,HARDEN,SB
; Function Attrs: norecurse nounwind readnone
define dso_local i32 @double_return(i32 %a, i32 %b) local_unnamed_addr {
entry:
%cmp = icmp sgt i32 %a, 0
br i1 %cmp, label %if.then, label %if.else
if.then: ; preds = %entry
%div = sdiv i32 %a, %b
ret i32 %div
if.else: ; preds = %entry
%div1 = sdiv i32 %b, %a
ret i32 %div1
; CHECK-LABEL: double_return:
; CHECK: {{ret$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
; CHECK: {{ret$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
; CHECK-NEXT: .Lfunc_end
}
@__const.indirect_branch.ptr = private unnamed_addr constant [2 x i8*] [i8* blockaddress(@indirect_branch, %return), i8* blockaddress(@indirect_branch, %l2)], align 8
; Function Attrs: norecurse nounwind readnone
define dso_local i32 @indirect_branch(i32 %a, i32 %b, i32 %i) {
; CHECK-LABEL: indirect_branch:
entry:
%idxprom = sext i32 %i to i64
%arrayidx = getelementptr inbounds [2 x i8*], [2 x i8*]* @__const.indirect_branch.ptr, i64 0, i64 %idxprom
%0 = load i8*, i8** %arrayidx, align 8
indirectbr i8* %0, [label %return, label %l2]
; CHECK: br x
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
l2: ; preds = %entry
br label %return
; CHECK: {{ret$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
return: ; preds = %entry, %l2
%retval.0 = phi i32 [ 1, %l2 ], [ 0, %entry ]
ret i32 %retval.0
; CHECK: {{ret$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
; CHECK-NEXT: .Lfunc_end
}
; Check that RETAA and RETAB instructions are also protected as expected.
define dso_local i32 @ret_aa(i32 returned %a) local_unnamed_addr "target-features"="+neon,+v8.3a" "sign-return-address"="all" "sign-return-address-key"="a_key" {
entry:
; CHECK-LABEL: ret_aa:
; CHECK: {{ retaa$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
; CHECK-NEXT: .Lfunc_end
ret i32 %a
}
define dso_local i32 @ret_ab(i32 returned %a) local_unnamed_addr "target-features"="+neon,+v8.3a" "sign-return-address"="all" "sign-return-address-key"="b_key" {
entry:
; CHECK-LABEL: ret_ab:
; CHECK: {{ retab$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
; CHECK-NEXT: .Lfunc_end
ret i32 %a
}
define i32 @asmgoto() {
entry:
; CHECK-LABEL: asmgoto:
callbr void asm sideeffect "B $0", "i"(i8* blockaddress(@asmgoto, %d))
to label %asm.fallthrough [label %d]
; The asm goto above produces a direct branch:
; CHECK: //APP
; CHECK-NEXT: {{^[ \t]+b }}
; CHECK-NEXT: //NO_APP
; For direct branches, no mitigation is needed.
; ISDDSB-NOT: dsb sy
; SB-NOT: {{ sb$}}
asm.fallthrough: ; preds = %entry
ret i32 0
; CHECK: {{ret$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
d: ; preds = %asm.fallthrough, %entry
ret i32 1
; CHECK: {{ret$}}
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: {{ sb$}}
; CHECK-NEXT: .Lfunc_end
}
define dso_local i32 @indirect_call(
i32 (...)* nocapture %f1, i32 (...)* nocapture %f2) {
entry:
; CHECK-LABEL: indirect_call:
%callee.knr.cast = bitcast i32 (...)* %f1 to i32 ()*
%call = tail call i32 %callee.knr.cast()
; HARDEN: bl {{__llvm_slsblr_thunk_x[0-9]+$}}
%callee.knr.cast1 = bitcast i32 (...)* %f2 to i32 ()*
%call2 = tail call i32 %callee.knr.cast1()
; HARDEN: bl {{__llvm_slsblr_thunk_x[0-9]+$}}
%add = add nsw i32 %call2, %call
ret i32 %add
; CHECK: .Lfunc_end
}
; verify calling through a function pointer.
@a = dso_local local_unnamed_addr global i32 (...)* null, align 8
@b = dso_local local_unnamed_addr global i32 0, align 4
define dso_local void @indirect_call_global() local_unnamed_addr {
; CHECK-LABEL: indirect_call_global:
entry:
%0 = load i32 ()*, i32 ()** bitcast (i32 (...)** @a to i32 ()**), align 8
%call = tail call i32 %0() nounwind
; HARDEN: bl {{__llvm_slsblr_thunk_x[0-9]+$}}
store i32 %call, i32* @b, align 4
ret void
; CHECK: .Lfunc_end
}
; Verify that neither x16 nor x17 are used when the BLR mitigation is enabled,
; as a linker is allowed to clobber x16 or x17 on calls, which would break the
; correct execution of the code sequence produced by the mitigation. The below
; test attempts to force *%f into x16 using inline assembly.
define i64 @check_x16(i64 ()** nocapture readonly %fp, i64 ()** nocapture readonly %fp2) "target-features"="+neon,+reserve-x10,+reserve-x11,+reserve-x12,+reserve-x13,+reserve-x14,+reserve-x15,+reserve-x18,+reserve-x20,+reserve-x21,+reserve-x22,+reserve-x23,+reserve-x24,+reserve-x25,+reserve-x26,+reserve-x27,+reserve-x28,+reserve-x30,+reserve-x9" {
entry:
; CHECK-LABEL: check_x16:
%f = load i64 ()*, i64 ()** %fp, align 8
%x16_f = tail call i64 ()* asm "add $0, $1, #0", "={x16},{x16}"(i64 ()* %f) nounwind
%call1 = call i64 %x16_f()
; NOHARDEN: blr x16
; ISBDSB-NOT: bl __llvm_slsblr_thunk_x16
; SB-NOT: bl __llvm_slsblr_thunk_x16
; CHECK
ret i64 %call1
; CHECK: .Lfunc_end
}
; Verify that the transformation works correctly for x29 when it is not
; reserved to be used as a frame pointer.
; Since this is sensitive to register allocation choices, only check this with
; DAGIsel to avoid too much accidental breaking of this test that is a bit
; brittle.
define i64 @check_x29(i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** nocapture readonly %fp,
i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** nocapture readonly %fp2,
i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** nocapture readonly %fp3)
"target-features"="+neon,+reserve-x10,+reserve-x11,+reserve-x12,+reserve-x13,+reserve-x14,+reserve-x15,+reserve-x18,+reserve-x20,+reserve-x21,+reserve-x22,+reserve-x23,+reserve-x24,+reserve-x25,+reserve-x26,+reserve-x27,+reserve-x28,+reserve-x9"
"frame-pointer"="none"
{
entry:
; CHECK-LABEL: check_x29:
%0 = load i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)*, i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** %fp, align 8
%1 = bitcast i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** %fp2 to i8**
%2 = load i8*, i8** %1, align 8
%3 = load i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)*, i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** %fp2, align 8
%4 = bitcast i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** %fp3 to i8**
%5 = load i8*, i8** %4, align 8
%6 = load i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)*, i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** %fp3, align 8
%7 = bitcast i64 (i8*, i8*, i64, i64, i64, i64, i64, i64)** %fp to i8**
%8 = load i8*, i8** %7, align 8
%call = call i64 %0(i8* %2, i8* %5, i64 0, i64 0, i64 0, i64 0, i64 0, i64 0)
%call1 = call i64 %3(i8* %2, i8* %5, i64 0, i64 0, i64 0, i64 0, i64 0, i64 0)
; NOHARDEN: blr x29
; ISBDSBDAGISEL: bl __llvm_slsblr_thunk_x29
; SBDAGISEL: bl __llvm_slsblr_thunk_x29
; CHECK
%call2 = call i64 %6(i8* %2, i8* %8, i64 0, i64 0, i64 0, i64 0, i64 0, i64 0)
%add = add nsw i64 %call1, %call
%add1 = add nsw i64 %call2, %add
ret i64 %add1
; CHECK: .Lfunc_end
}
; HARDEN-label: __llvm_slsblr_thunk_x0:
; HARDEN: mov x16, x0
; HARDEN: br x16
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: dsb sy
; SB-NEXT: isb
; HARDEN-NEXT: .Lfunc_end
; HARDEN-COMDAT: .section .text.__llvm_slsblr_thunk_x19
; HARDEN-COMDAT: .hidden __llvm_slsblr_thunk_x19
; HARDEN-COMDAT: .weak __llvm_slsblr_thunk_x19
; HARDEN-COMDAT: .type __llvm_slsblr_thunk_x19,@function
; HARDEN-COMDAT-OFF-NOT: .section .text.__llvm_slsblr_thunk_x19
; HARDEN-COMDAT-OFF-NOT: .hidden __llvm_slsblr_thunk_x19
; HARDEN-COMDAT-OFF-NOT: .weak __llvm_slsblr_thunk_x19
; HARDEN-COMDAT-OFF: .type __llvm_slsblr_thunk_x19,@function
; HARDEN-label: __llvm_slsblr_thunk_x19:
; HARDEN: mov x16, x19
; HARDEN: br x16
; ISBDSB-NEXT: dsb sy
; ISBDSB-NEXT: isb
; SB-NEXT: dsb sy
; SB-NEXT: isb
; HARDEN-NEXT: .Lfunc_end
|
