[llvm] r337672 - [x86/SLH] Add a test covering indirect forms of control flow. NFC.

Chandler Carruth via llvm-commits llvm-commits at lists.llvm.org
Mon Jul 23 00:51:51 PDT 2018


Author: chandlerc
Date: Mon Jul 23 00:51:51 2018
New Revision: 337672

URL: http://llvm.org/viewvc/llvm-project?rev=337672&view=rev
Log:
[x86/SLH] Add a test covering indirect forms of control flow. NFC.

This specifically covers different ways of making indirect calls and
jumps. There are some bugs in SLH that I will be fixing in subsequent
patches where the diff in the generated instructions makes the bug fix
much more clear, so just checking in a baseline of this test to start.

I'm also going to be adding direct mitigation for variant 1.2 which this
file very specifically tests in the various forms it can arise on x86.
Again, the diff to the generated instructions should make the change for
that much more clear, so having the test as a baseline seems useful.

Added:
    llvm/trunk/test/CodeGen/X86/speculative-load-hardening-indirect.ll

Added: llvm/trunk/test/CodeGen/X86/speculative-load-hardening-indirect.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/speculative-load-hardening-indirect.ll?rev=337672&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/speculative-load-hardening-indirect.ll (added)
+++ llvm/trunk/test/CodeGen/X86/speculative-load-hardening-indirect.ll Mon Jul 23 00:51:51 2018
@@ -0,0 +1,234 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=x86_64-unknown-linux-gnu -x86-speculative-load-hardening -data-sections | FileCheck %s --check-prefix=X64
+;
+; FIXME: Add support for 32-bit.
+
+ at global_fnptr = external global i32 ()*
+
+ at global_blockaddrs = constant [4 x i8*] [
+  i8* blockaddress(@test_indirectbr_global, %bb0),
+  i8* blockaddress(@test_indirectbr_global, %bb1),
+  i8* blockaddress(@test_indirectbr_global, %bb2),
+  i8* blockaddress(@test_indirectbr_global, %bb3)
+]
+
+define i32 @test_indirect_call(i32 ()** %ptr) nounwind {
+; X64-LABEL: test_indirect_call:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    pushq %rbx
+; X64-NEXT:    movq %rsp, %rbx
+; X64-NEXT:    movq $-1, %rax
+; X64-NEXT:    sarq $63, %rbx
+; X64-NEXT:    orq %rbx, %rdi
+; X64-NEXT:    callq *(%rdi)
+; X64-NEXT:    shlq $47, %rbx
+; X64-NEXT:    orq %rbx, %rsp
+; X64-NEXT:    popq %rbx
+; X64-NEXT:    retq
+entry:
+  %fp = load i32 ()*, i32 ()** %ptr
+  %v = call i32 %fp()
+  ret i32 %v
+}
+
+define i32 @test_indirect_tail_call(i32 ()** %ptr) nounwind {
+; X64-LABEL: test_indirect_tail_call:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    movq %rsp, %rax
+; X64-NEXT:    movq $-1, %rcx
+; X64-NEXT:    sarq $63, %rax
+; X64-NEXT:    movq %rax, %rcx
+; X64-NEXT:    shlq $47, %rcx
+; X64-NEXT:    orq %rcx, %rsp
+; X64-NEXT:    shlq $47, %rax
+; X64-NEXT:    orq %rax, %rsp
+; X64-NEXT:    jmpq *(%rdi) # TAILCALL
+entry:
+  %fp = load i32 ()*, i32 ()** %ptr
+  %v = tail call i32 %fp()
+  ret i32 %v
+}
+
+define i32 @test_indirect_call_global() nounwind {
+; X64-LABEL: test_indirect_call_global:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    pushq %rax
+; X64-NEXT:    movq %rsp, %rax
+; X64-NEXT:    movq $-1, %rcx
+; X64-NEXT:    sarq $63, %rax
+; X64-NEXT:    shlq $47, %rax
+; X64-NEXT:    orq %rax, %rsp
+; X64-NEXT:    callq *{{.*}}(%rip)
+; X64-NEXT:    movq %rsp, %rcx
+; X64-NEXT:    sarq $63, %rcx
+; X64-NEXT:    shlq $47, %rcx
+; X64-NEXT:    orq %rcx, %rsp
+; X64-NEXT:    popq %rcx
+; X64-NEXT:    retq
+entry:
+  %fp = load i32 ()*, i32 ()** @global_fnptr
+  %v = call i32 %fp()
+  ret i32 %v
+}
+
+define i32 @test_indirect_tail_call_global() nounwind {
+; X64-LABEL: test_indirect_tail_call_global:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    movq %rsp, %rax
+; X64-NEXT:    movq $-1, %rcx
+; X64-NEXT:    sarq $63, %rax
+; X64-NEXT:    movq %rax, %rcx
+; X64-NEXT:    shlq $47, %rcx
+; X64-NEXT:    orq %rcx, %rsp
+; X64-NEXT:    shlq $47, %rax
+; X64-NEXT:    orq %rax, %rsp
+; X64-NEXT:    jmpq *{{.*}}(%rip) # TAILCALL
+entry:
+  %fp = load i32 ()*, i32 ()** @global_fnptr
+  %v = tail call i32 %fp()
+  ret i32 %v
+}
+
+define i32 @test_indirectbr(i8** %ptr) nounwind {
+; X64-LABEL: test_indirectbr:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    movq %rsp, %rcx
+; X64-NEXT:    movq $-1, %rax
+; X64-NEXT:    sarq $63, %rcx
+; X64-NEXT:    orq %rcx, %rdi
+; X64-NEXT:    jmpq *(%rdi)
+; X64-NEXT:  .LBB4_1: # %bb0
+; X64-NEXT:    movl $2, %eax
+; X64-NEXT:    jmp .LBB4_2
+; X64-NEXT:  .LBB4_4: # %bb2
+; X64-NEXT:    movl $13, %eax
+; X64-NEXT:    jmp .LBB4_2
+; X64-NEXT:  .LBB4_5: # %bb3
+; X64-NEXT:    movl $42, %eax
+; X64-NEXT:    jmp .LBB4_2
+; X64-NEXT:  .LBB4_3: # %bb1
+; X64-NEXT:    movl $7, %eax
+; X64-NEXT:  .LBB4_2: # %bb0
+; X64-NEXT:    shlq $47, %rcx
+; X64-NEXT:    orq %rcx, %rsp
+; X64-NEXT:    retq
+entry:
+  %a = load i8*, i8** %ptr
+  indirectbr i8* %a, [ label %bb0, label %bb1, label %bb2, label %bb3 ]
+
+bb0:
+  ret i32 2
+
+bb1:
+  ret i32 7
+
+bb2:
+  ret i32 13
+
+bb3:
+  ret i32 42
+}
+
+define i32 @test_indirectbr_global(i32 %idx) nounwind {
+; X64-LABEL: test_indirectbr_global:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    movq %rsp, %rcx
+; X64-NEXT:    movq $-1, %rax
+; X64-NEXT:    sarq $63, %rcx
+; X64-NEXT:    movslq %edi, %rax
+; X64-NEXT:    orq %rcx, %rax
+; X64-NEXT:    jmpq *global_blockaddrs(,%rax,8)
+; X64-NEXT:  .Ltmp0: # Block address taken
+; X64-NEXT:  .LBB5_1: # %bb0
+; X64-NEXT:    movl $2, %eax
+; X64-NEXT:    jmp .LBB5_2
+; X64-NEXT:  .Ltmp1: # Block address taken
+; X64-NEXT:  .LBB5_4: # %bb2
+; X64-NEXT:    movl $13, %eax
+; X64-NEXT:    jmp .LBB5_2
+; X64-NEXT:  .Ltmp2: # Block address taken
+; X64-NEXT:  .LBB5_5: # %bb3
+; X64-NEXT:    movl $42, %eax
+; X64-NEXT:    jmp .LBB5_2
+; X64-NEXT:  .Ltmp3: # Block address taken
+; X64-NEXT:  .LBB5_3: # %bb1
+; X64-NEXT:    movl $7, %eax
+; X64-NEXT:  .LBB5_2: # %bb0
+; X64-NEXT:    shlq $47, %rcx
+; X64-NEXT:    orq %rcx, %rsp
+; X64-NEXT:    retq
+entry:
+  %ptr = getelementptr [4 x i8*], [4 x i8*]* @global_blockaddrs, i32 0, i32 %idx
+  %a = load i8*, i8** %ptr
+  indirectbr i8* %a, [ label %bb0, label %bb1, label %bb2, label %bb3 ]
+
+bb0:
+  ret i32 2
+
+bb1:
+  ret i32 7
+
+bb2:
+  ret i32 13
+
+bb3:
+  ret i32 42
+}
+
+; This function's switch is crafted to trigger jump-table lowering in the x86
+; backend so that we can test how the exact jump table lowering behaves.
+define i32 @test_switch_jumptable(i32 %idx) nounwind {
+; X64-LABEL: test_switch_jumptable:
+; X64:       # %bb.0: # %entry
+; X64-NEXT:    movq %rsp, %rcx
+; X64-NEXT:    movq $-1, %rax
+; X64-NEXT:    sarq $63, %rcx
+; X64-NEXT:    cmpl $3, %edi
+; X64-NEXT:    ja .LBB6_2
+; X64-NEXT:  # %bb.1: # %entry
+; X64-NEXT:    cmovaq %rax, %rcx
+; X64-NEXT:    movl %edi, %eax
+; X64-NEXT:    orq %rcx, %rax
+; X64-NEXT:    jmpq *.LJTI6_0(,%rax,8)
+; X64-NEXT:  .LBB6_3: # %bb1
+; X64-NEXT:    movl $7, %eax
+; X64-NEXT:    jmp .LBB6_4
+; X64-NEXT:  .LBB6_2: # %bb0
+; X64-NEXT:    cmovbeq %rax, %rcx
+; X64-NEXT:    movl $2, %eax
+; X64-NEXT:    jmp .LBB6_4
+; X64-NEXT:  .LBB6_5: # %bb2
+; X64-NEXT:    movl $13, %eax
+; X64-NEXT:    jmp .LBB6_4
+; X64-NEXT:  .LBB6_6: # %bb3
+; X64-NEXT:    movl $42, %eax
+; X64-NEXT:    jmp .LBB6_4
+; X64-NEXT:  .LBB6_7: # %bb5
+; X64-NEXT:    movl $11, %eax
+; X64-NEXT:  .LBB6_4: # %bb1
+; X64-NEXT:    shlq $47, %rcx
+; X64-NEXT:    orq %rcx, %rsp
+; X64-NEXT:    retq
+entry:
+  switch i32 %idx, label %bb0 [
+    i32 0, label %bb1
+    i32 1, label %bb2
+    i32 2, label %bb3
+    i32 3, label %bb5
+  ]
+
+bb0:
+  ret i32 2
+
+bb1:
+  ret i32 7
+
+bb2:
+  ret i32 13
+
+bb3:
+  ret i32 42
+
+bb5:
+  ret i32 11
+}




More information about the llvm-commits mailing list