[IR] Mark llvm.trap as memory(inaccessiblemem: write)

Traps will not read/write the program state but they need an effect for preservation, similar to `llvm.assume`. We really want a new memory kind for that (see TODO), but for now `inaccessiblemem: write` is better than any possible effect. Differential Revision: https://reviews.llvm.org/D156476
llvm · Jul 31, 2023 · 6fa8244 · 6fa8244
1 parent deb0ea3
commit 6fa8244
Show file tree

Hide file tree

Showing 15 changed files with 32 additions and 29 deletions.
diff --git a/llvm/include/llvm/IR/Intrinsics.td b/llvm/include/llvm/IR/Intrinsics.td
@@ -1670,8 +1670,10 @@ def int_coro_subfn_addr : DefaultAttrsIntrinsic<
 
 ///===-------------------------- Other Intrinsics --------------------------===//
 //
-def int_trap : Intrinsic<[], [], [IntrNoReturn, IntrCold]>,
-               ClangBuiltin<"__builtin_trap">;
+// TODO: We should introduce a new memory kind fo traps (and other side effects 
+//       we only model to keep things alive).
+def int_trap : Intrinsic<[], [], [IntrNoReturn, IntrCold, IntrInaccessibleMemOnly,
+               IntrWriteMem]>, ClangBuiltin<"__builtin_trap">;
 def int_debugtrap : Intrinsic<[]>,
                     ClangBuiltin<"__builtin_debugtrap">;
 def int_ubsantrap : Intrinsic<[], [llvm_i8_ty],

diff --git a/llvm/test/Feature/intrinsics.ll b/llvm/test/Feature/intrinsics.ll
@@ -70,4 +70,4 @@ define void @trap() {
 }
 
 ; CHECK: attributes #0 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
-; CHECK: attributes #1 = { cold noreturn nounwind }
+; CHECK: attributes #1 = { cold noreturn nounwind memory(inaccessiblemem: write) }
diff --git a/llvm/test/Transforms/Attributor/cgscc_bugs.ll b/llvm/test/Transforms/Attributor/cgscc_bugs.ll
@@ -23,7 +23,7 @@ define linkonce_odr hidden { ptr, i64 } @f3(i64 %0) align 2 {
 ; CHECK-SAME: (i64 [[TMP0:%.*]]) align 2 {
 ; CHECK-NEXT:    [[TMP2:%.*]] = call i32 @f4()
 ; CHECK-NEXT:    [[TMP3:%.*]] = zext i32 [[TMP2]] to i64
-; CHECK-NEXT:    call void @f5(i64 [[TMP3]], i64 [[TMP0]]) #[[ATTR0:[0-9]+]]
+; CHECK-NEXT:    call void @f5(i64 [[TMP3]], i64 [[TMP0]]) #[[ATTR2:[0-9]+]]
 ; CHECK-NEXT:    ret { ptr, i64 } undef
 ;
   %2 = call i32 @f4()
@@ -40,18 +40,18 @@ define linkonce_odr hidden i32 @f4() align 2 {
 }
 
 define internal void @f5(i64 %0, i64 %1) {
-; CHECK: Function Attrs: nounwind
+; CHECK: Function Attrs: nounwind memory(inaccessiblemem: write)
 ; CHECK-LABEL: define {{[^@]+}}@f5
-; CHECK-SAME: (i64 [[TMP0:%.*]], i64 [[TMP1:%.*]]) #[[ATTR0]] {
+; CHECK-SAME: (i64 [[TMP0:%.*]], i64 [[TMP1:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-NEXT:    br label [[TMP3:%.*]]
 ; CHECK:       3:
-; CHECK-NEXT:    call void @f6(i64 [[TMP0]]) #[[ATTR0]]
+; CHECK-NEXT:    call void @f6(i64 [[TMP0]]) #[[ATTR2]]
 ; CHECK-NEXT:    [[TMP4:%.*]] = icmp sgt i64 [[TMP1]], [[TMP0]]
 ; CHECK-NEXT:    br i1 [[TMP4]], label [[TMP5:%.*]], label [[TMP6:%.*]]
 ; CHECK:       5:
 ; CHECK-NEXT:    ret void
 ; CHECK:       6:
-; CHECK-NEXT:    call void @f5(i64 [[TMP0]], i64 [[TMP1]]) #[[ATTR0]]
+; CHECK-NEXT:    call void @f5(i64 [[TMP0]], i64 [[TMP1]]) #[[ATTR2]]
 ; CHECK-NEXT:    br label [[TMP3]]
 ;
   br label %3
@@ -70,13 +70,13 @@ define internal void @f5(i64 %0, i64 %1) {
 }
 
 define internal void @f6(i64 %0) {
-; CHECK: Function Attrs: nounwind
+; CHECK: Function Attrs: nounwind memory(inaccessiblemem: write)
 ; CHECK-LABEL: define {{[^@]+}}@f6
 ; CHECK-SAME: (i64 [[TMP0:%.*]]) #[[ATTR0]] {
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp sgt i64 [[TMP0]], 0
 ; CHECK-NEXT:    br i1 [[TMP2]], label [[TMP3:%.*]], label [[TMP4:%.*]]
 ; CHECK:       3:
-; CHECK-NEXT:    call void @llvm.trap() #[[ATTR2:[0-9]+]]
+; CHECK-NEXT:    call void @llvm.trap() #[[ATTR3:[0-9]+]]
 ; CHECK-NEXT:    unreachable
 ; CHECK:       4:
 ; CHECK-NEXT:    ret void
@@ -98,9 +98,10 @@ declare void @llvm.trap() #0
 attributes #0 = { cold noreturn nounwind }
 
 ;.
-; CHECK: attributes #[[ATTR0]] = { nounwind }
-; CHECK: attributes #[[ATTR1:[0-9]+]] = { cold noreturn nounwind }
-; CHECK: attributes #[[ATTR2]] = { noreturn }
+; CHECK: attributes #[[ATTR0]] = { nounwind memory(inaccessiblemem: write) }
+; CHECK: attributes #[[ATTR1:[0-9]+]] = { cold noreturn nounwind memory(inaccessiblemem: write) }
+; CHECK: attributes #[[ATTR2]] = { nounwind memory(write) }
+; CHECK: attributes #[[ATTR3]] = { noreturn memory(write) }
 ;.
 ;; NOTE: These prefixes are unused and the list is autogenerated. Do not add tests below this line:
 ; CGSCC: {{.*}}

diff --git a/llvm/test/Transforms/LowerGlobalDestructors/non-literal-type.ll b/llvm/test/Transforms/LowerGlobalDestructors/non-literal-type.ll
@@ -32,5 +32,5 @@ declare void @dtor()
 ; CHECK-NEXT:    ret void
 ;
 ;.
-; CHECK: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind }
+; CHECK: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind memory(inaccessiblemem: write) }
 ;.
diff --git a/llvm/test/Transforms/SimplifyCFG/switch-on-const-select.ll b/llvm/test/Transforms/SimplifyCFG/switch-on-const-select.ll
@@ -158,4 +158,4 @@ declare void @llvm.trap() nounwind noreturn
 declare void @bees.a() nounwind
 declare void @bees.b() nounwind
 
-; CHECK: attributes #1 = { cold noreturn nounwind }
+; CHECK: attributes #1 = { cold noreturn nounwind memory(inaccessiblemem: write) }
diff --git a/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll b/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll
@@ -32,5 +32,5 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
diff --git a/...st/tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.generated.expected b/...st/tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.generated.expected
@@ -33,7 +33,7 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
 ; CHECK-LABEL: @foo(
 ; CHECK-NEXT:    [[TMP2:%.*]] = icmp eq i32 [[TMP0:%.*]], 0

diff --git a/.../UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.generated.globals.expected b/.../UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.generated.globals.expected
@@ -33,7 +33,7 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
 ;.
 ; CHECK: @[[G:[a-zA-Z0-9_$"\\.-]+]] = external dso_local global i32, align 4
@@ -78,7 +78,7 @@ declare void @_Z10sideeffectv()
 ; CHECK-NEXT:    unreachable
 ;
 ;.
-; CHECK: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind }
+; CHECK: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind memory(inaccessiblemem: write) }
 ; CHECK: attributes #[[ATTR1:[0-9]+]] = { cold minsize noreturn }
 ; CHECK: attributes #[[ATTR2]] = { noinline }
 ;.
diff --git a/.../tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.nogenerated.expected b/.../tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.nogenerated.expected
@@ -53,5 +53,5 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
diff --git a/...pdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.nogenerated.globals.expected b/...pdateTestChecks/update_test_checks/Inputs/generated_funcs.ll.nogenerated.globals.expected
@@ -56,10 +56,10 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
 ;.
-; CHECK: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind }
+; CHECK: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind memory(inaccessiblemem: write) }
 ; CHECK: attributes #[[ATTR1:[0-9]+]] = { cold minsize noreturn }
 ; CHECK: attributes #[[ATTR2]] = { noinline }
 ;.
diff --git a/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll b/llvm/test/tools/UpdateTestChecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll
@@ -33,5 +33,5 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
diff --git a/...teTestChecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.generated.expected b/...teTestChecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.generated.expected
@@ -34,7 +34,7 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
 ; REUSE-LABEL: @foo(
 ; REUSE-NEXT:    [[TMP2:%.*]] = icmp eq i32 [[TMP0:%.*]], 0

diff --git a/...ecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.generated.globals.expected b/...ecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.generated.globals.expected
@@ -34,7 +34,7 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
 ;.
 ; REUSE: @[[G:[a-zA-Z0-9_$"\\.-]+]] = external dso_local global i32, align 4
@@ -79,7 +79,7 @@ declare void @_Z10sideeffectv()
 ; REUSE-NEXT:    unreachable
 ;
 ;.
-; REUSE: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind }
+; REUSE: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind memory(inaccessiblemem: write) }
 ; REUSE: attributes #[[ATTR1:[0-9]+]] = { cold minsize noreturn }
 ; REUSE: attributes #[[ATTR2]] = { noinline }
 ;.
diff --git a/...TestChecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.nogenerated.expected b/...TestChecks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.nogenerated.expected
@@ -54,5 +54,5 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
diff --git a/...ks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.nogenerated.globals.expected b/...ks/update_test_checks/Inputs/generated_funcs_prefix_reuse.ll.nogenerated.globals.expected
@@ -57,10 +57,10 @@ exit:
   ret void
 }
 
-declare void @llvm.trap() noreturn cold
+declare void @llvm.trap() noreturn cold memory(inaccessiblemem: write)
 declare void @_Z10sideeffectv()
 ;.
-; REUSE: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind }
+; REUSE: attributes #[[ATTR0:[0-9]+]] = { cold noreturn nounwind memory(inaccessiblemem: write) }
 ; REUSE: attributes #[[ATTR1:[0-9]+]] = { cold minsize noreturn }
 ; REUSE: attributes #[[ATTR2]] = { noinline }
 ;.