[NFC][clang] Add ubsan-trap-merge.ll test to show absence of nomerge …

…considered harmful (llvm#117657) These testcases demonstrate that ubsan intrinsics are merged in the backend iff nomerge is missing from ubsantrap intrinsics. This is based on the observation and testcase by Vitaly Buka in llvm#83470.
kraj · Nov 26, 2024 · dde7f4d · dde7f4d
1 parent 1b68b33
commit dde7f4d
Show file tree

Hide file tree

Showing 2 changed files with 367 additions and 0 deletions.
diff --git a/llvm/test/CodeGen/X86/ubsan-trap-merge.ll b/llvm/test/CodeGen/X86/ubsan-trap-merge.ll
@@ -0,0 +1,181 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -O3 -mtriple x86_64 -filetype asm -o - %s | FileCheck %s
+;
+; This test shows that ubsantrap can, in the absence of nomerge, be merged by
+; the backend into a single ud1 instruction (thus making debugging difficult).
+;
+; The LLVM IR was generated from clang/test/CodeGen/ubsan-trap-merge.c.
+;
+; ModuleID = '../clang/test/CodeGen/ubsan-trap-merge.c'
+source_filename = "../clang/test/CodeGen/ubsan-trap-merge.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function Attrs: nounwind uwtable
+define dso_local range(i32 -2147483523, -2147483648) i32 @f(i32 noundef %x) local_unnamed_addr #0 {
+; CHECK-LABEL: f:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $125, %edi
+; CHECK-NEXT:    jo .LBB0_1
+; CHECK-NEXT:  # %bb.2: # %cont
+; CHECK-NEXT:    movl %edi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB0_1: # %trap
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 125), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %entry
+  %2 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  ret i32 %2
+}
+
+; Function Attrs: mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32) #1
+
+; Function Attrs: cold noreturn nounwind
+declare void @llvm.ubsantrap(i8 immarg) #2
+
+; Function Attrs: nounwind uwtable
+define dso_local range(i32 -2147483521, -2147483648) i32 @g(i32 noundef %x) local_unnamed_addr #0 {
+; CHECK-LABEL: g:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $127, %edi
+; CHECK-NEXT:    jo .LBB1_1
+; CHECK-NEXT:  # %bb.2: # %cont
+; CHECK-NEXT:    movl %edi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB1_1: # %trap
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 127), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %entry
+  %2 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  ret i32 %2
+}
+
+; Function Attrs: nounwind uwtable
+define dso_local range(i32 -2147483521, -2147483648) i32 @h(i32 noundef %x, i32 noundef %y) local_unnamed_addr #0 {
+; CHECK-LABEL: h:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $127, %edi
+; CHECK-NEXT:    jo .LBB2_3
+; CHECK-NEXT:  # %bb.1: # %cont
+; CHECK-NEXT:    addl $129, %esi
+; CHECK-NEXT:    jo .LBB2_4
+; CHECK-NEXT:  # %bb.2: # %cont2
+; CHECK-NEXT:    cmpl %esi, %edi
+; CHECK-NEXT:    cmovll %edi, %esi
+; CHECK-NEXT:    movl %esi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB2_3: # %trap
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+; CHECK-NEXT:  .LBB2_4: # %trap1
+; CHECK-NEXT:    ud1l 4(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 127), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %entry
+  %2 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %y, i32 129), !nosanitize !5
+  %3 = extractvalue { i32, i1 } %2, 1, !nosanitize !5
+  br i1 %3, label %trap1, label %cont2, !nosanitize !5
+
+trap1:                                            ; preds = %cont
+  tail call void @llvm.ubsantrap(i8 4) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont2:                                            ; preds = %cont
+  %4 = extractvalue { i32, i1 } %2, 0, !nosanitize !5
+  %5 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  %cond = tail call i32 @llvm.smin.i32(i32 %5, i32 %4)
+  ret i32 %cond
+}
+
+; Function Attrs: nounwind uwtable
+define dso_local noundef i32 @m(i32 noundef %x, i32 noundef %y) local_unnamed_addr #0 {
+; CHECK-LABEL: m:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $125, %edi
+; CHECK-NEXT:    jo .LBB3_4
+; CHECK-NEXT:  # %bb.1: # %f.exit
+; CHECK-NEXT:    addl $127, %esi
+; CHECK-NEXT:    jo .LBB3_4
+; CHECK-NEXT:  # %bb.2: # %g.exit
+; CHECK-NEXT:    addl %esi, %edi
+; CHECK-NEXT:    jo .LBB3_4
+; CHECK-NEXT:  # %bb.3: # %cont
+; CHECK-NEXT:    movl %edi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB3_4: # %trap.i
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 125), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap.i, label %f.exit, !nosanitize !5
+
+trap.i:                                           ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+f.exit:                                           ; preds = %entry
+  %2 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %y, i32 127), !nosanitize !5
+  %3 = extractvalue { i32, i1 } %2, 1, !nosanitize !5
+  br i1 %3, label %trap.i2, label %g.exit, !nosanitize !5
+
+trap.i2:                                          ; preds = %f.exit
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+g.exit:                                           ; preds = %f.exit
+  %4 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  %5 = extractvalue { i32, i1 } %2, 0, !nosanitize !5
+  %6 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %4, i32 %5), !nosanitize !5
+  %7 = extractvalue { i32, i1 } %6, 1, !nosanitize !5
+  br i1 %7, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %g.exit
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %g.exit
+  %8 = extractvalue { i32, i1 } %6, 0, !nosanitize !5
+  ret i32 %8
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare i32 @llvm.smin.i32(i32, i32) #3
+
+attributes #0 = { nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #1 = { mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none) }
+attributes #2 = { cold noreturn nounwind }
+attributes #3 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
+attributes #4 = { noreturn nounwind }
+
+!llvm.module.flags = !{!0, !1, !2, !3}
+!llvm.ident = !{!4}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 8, !"PIC Level", i32 2}
+!2 = !{i32 7, !"PIE Level", i32 2}
+!3 = !{i32 7, !"uwtable", i32 2}
+!4 = !{!"clang version 20.0.0git (https://github.com/llvm/llvm-project.git fe3c23b439b9a2d00442d9bc6a4ca86f73066a3d)"}
+!5 = !{}
diff --git a/llvm/test/CodeGen/X86/ubsan-trap-nomerge.ll b/llvm/test/CodeGen/X86/ubsan-trap-nomerge.ll
@@ -0,0 +1,186 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -O3 -mtriple x86_64 -filetype asm -o - %s | FileCheck %s
+;
+; This tests that the nomerge attribute for ubsantrap works correctly i.e.,
+; they are lowered to separate ud1 instructions.
+;
+; The LLVM IR was generated from clang/test/CodeGen/ubsan-trap-merge.c with
+; 'nomerge' manually added to ubsantraps.
+;
+; ModuleID = '../clang/test/CodeGen/ubsan-trap-merge.c'
+source_filename = "../clang/test/CodeGen/ubsan-trap-merge.c"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+; Function Attrs: nounwind uwtable
+define dso_local range(i32 -2147483523, -2147483648) i32 @f(i32 noundef %x) local_unnamed_addr #0 {
+; CHECK-LABEL: f:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $125, %edi
+; CHECK-NEXT:    jo .LBB0_1
+; CHECK-NEXT:  # %bb.2: # %cont
+; CHECK-NEXT:    movl %edi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB0_1: # %trap
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 125), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %entry
+  %2 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  ret i32 %2
+}
+
+; Function Attrs: mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare { i32, i1 } @llvm.sadd.with.overflow.i32(i32, i32) #1
+
+; Function Attrs: cold noreturn nounwind
+declare void @llvm.ubsantrap(i8 immarg) #2
+
+; Function Attrs: nounwind uwtable
+define dso_local range(i32 -2147483521, -2147483648) i32 @g(i32 noundef %x) local_unnamed_addr #0 {
+; CHECK-LABEL: g:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $127, %edi
+; CHECK-NEXT:    jo .LBB1_1
+; CHECK-NEXT:  # %bb.2: # %cont
+; CHECK-NEXT:    movl %edi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB1_1: # %trap
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 127), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %entry
+  %2 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  ret i32 %2
+}
+
+; Function Attrs: nounwind uwtable
+define dso_local range(i32 -2147483521, -2147483648) i32 @h(i32 noundef %x, i32 noundef %y) local_unnamed_addr #0 {
+; CHECK-LABEL: h:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $127, %edi
+; CHECK-NEXT:    jo .LBB2_3
+; CHECK-NEXT:  # %bb.1: # %cont
+; CHECK-NEXT:    addl $129, %esi
+; CHECK-NEXT:    jo .LBB2_4
+; CHECK-NEXT:  # %bb.2: # %cont2
+; CHECK-NEXT:    cmpl %esi, %edi
+; CHECK-NEXT:    cmovll %edi, %esi
+; CHECK-NEXT:    movl %esi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB2_3: # %trap
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+; CHECK-NEXT:  .LBB2_4: # %trap1
+; CHECK-NEXT:    ud1l 4(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 127), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %entry
+  %2 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %y, i32 129), !nosanitize !5
+  %3 = extractvalue { i32, i1 } %2, 1, !nosanitize !5
+  br i1 %3, label %trap1, label %cont2, !nosanitize !5
+
+trap1:                                            ; preds = %cont
+  tail call void @llvm.ubsantrap(i8 4) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont2:                                            ; preds = %cont
+  %4 = extractvalue { i32, i1 } %2, 0, !nosanitize !5
+  %5 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  %cond = tail call i32 @llvm.smin.i32(i32 %5, i32 %4)
+  ret i32 %cond
+}
+
+; Function Attrs: nounwind uwtable
+define dso_local noundef i32 @m(i32 noundef %x, i32 noundef %y) local_unnamed_addr #0 {
+; CHECK-LABEL: m:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    addl $125, %edi
+; CHECK-NEXT:    jo .LBB3_4
+; CHECK-NEXT:  # %bb.1: # %f.exit
+; CHECK-NEXT:    addl $127, %esi
+; CHECK-NEXT:    jo .LBB3_5
+; CHECK-NEXT:  # %bb.2: # %g.exit
+; CHECK-NEXT:    addl %esi, %edi
+; CHECK-NEXT:    jo .LBB3_6
+; CHECK-NEXT:  # %bb.3: # %cont
+; CHECK-NEXT:    movl %edi, %eax
+; CHECK-NEXT:    retq
+; CHECK-NEXT:  .LBB3_4: # %trap.i
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+; CHECK-NEXT:  .LBB3_5: # %trap.i2
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+; CHECK-NEXT:  .LBB3_6: # %trap
+; CHECK-NEXT:    ud1l 2(%eax), %eax
+entry:
+  %0 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %x, i32 125), !nosanitize !5
+  %1 = extractvalue { i32, i1 } %0, 1, !nosanitize !5
+  br i1 %1, label %trap.i, label %f.exit, !nosanitize !5
+
+trap.i:                                           ; preds = %entry
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+f.exit:                                           ; preds = %entry
+  %2 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %y, i32 127), !nosanitize !5
+  %3 = extractvalue { i32, i1 } %2, 1, !nosanitize !5
+  br i1 %3, label %trap.i2, label %g.exit, !nosanitize !5
+
+trap.i2:                                          ; preds = %f.exit
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+g.exit:                                           ; preds = %f.exit
+  %4 = extractvalue { i32, i1 } %0, 0, !nosanitize !5
+  %5 = extractvalue { i32, i1 } %2, 0, !nosanitize !5
+  %6 = tail call { i32, i1 } @llvm.sadd.with.overflow.i32(i32 %4, i32 %5), !nosanitize !5
+  %7 = extractvalue { i32, i1 } %6, 1, !nosanitize !5
+  br i1 %7, label %trap, label %cont, !nosanitize !5
+
+trap:                                             ; preds = %g.exit
+  tail call void @llvm.ubsantrap(i8 2) #4, !nosanitize !5
+  unreachable, !nosanitize !5
+
+cont:                                             ; preds = %g.exit
+  %8 = extractvalue { i32, i1 } %6, 0, !nosanitize !5
+  ret i32 %8
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare i32 @llvm.smin.i32(i32, i32) #3
+
+attributes #0 = { nounwind uwtable "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #1 = { mustprogress nocallback nofree nosync nounwind speculatable willreturn memory(none) }
+attributes #2 = { cold noreturn nounwind }
+attributes #3 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
+attributes #4 = { nomerge noreturn nounwind }
+
+!llvm.module.flags = !{!0, !1, !2, !3}
+!llvm.ident = !{!4}
+
+!0 = !{i32 1, !"wchar_size", i32 4}
+!1 = !{i32 8, !"PIC Level", i32 2}
+!2 = !{i32 7, !"PIE Level", i32 2}
+!3 = !{i32 7, !"uwtable", i32 2}
+!4 = !{!"clang version 20.0.0git (https://github.com/llvm/llvm-project.git fe3c23b439b9a2d00442d9bc6a4ca86f73066a3d)"}
+!5 = !{}