[test] Simplify pr33641_remove_arg_dbgvalue.ll

[aeubanks]

Summary

This makes it pass under the NPM.
The legacy PM pass ran passes on SCCs in a different order, causing
argpromotion to not trigger on @bar().

[rnk]

The legacy PM pass ran passes on SCCs in a different order, causing
argpromotion to not trigger on @bar().

I see, so DSE would run, then bar would become unreferenced, and then there would be no reason to promote arguments?

llvm/test/Transforms/ArgumentPromotion/pr33641_remove_arg_dbgvalue.ll

23

I think it's generally good practice to keep around some CHECK lines for context, like this define @bar line. It helps to make the test more robust to future modifications that add code later with more dbg.values that might match this CHECK here.

[aeubanks]

add context CHECK

[aeubanks]

In D89889#2348178, @rnk wrote:

The legacy PM pass ran passes on SCCs in a different order, causing
argpromotion to not trigger on @bar().

I see, so DSE would run, then bar would become unreferenced, and then there would be no reason to promote arguments?

Actually, the legacy PM first ran passes on @foo(), then @bar() arbitrarily since it doesn't keep track of function references, only direct calls. In the NPM, it sees the reference of @bar() in @foo(), so properly first runs passes on @bar() then @foo().

[rnk]

lgtm

llvm/test/Transforms/ArgumentPromotion/pr33641_remove_arg_dbgvalue.ll

-; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --function-signature --scrub-attributes
-; RUN: opt -argpromotion -verify -dse -S %s -o - | FileCheck %s
+; RUN: opt -argpromotion -S %s -o - | FileCheck %s
+; RUN: opt -passes=argpromotion -S %s -o - | FileCheck %s
 
 ; Fix for PR33641. ArgumentPromotion removed the argument to bar but left the call to
 ; dbg.value which still used the removed argument.
 
 ; The %p argument should be removed, and the use of it in dbg.value should be
 ; changed to undef.
 
-%p_t = type i16*
-%fun_t = type void (%p_t)*
-
+%fun_t = type void (i16*)*
 define void @foo() {
-; CHECK-LABEL: define {{[^@]+}}@foo()
-; CHECK-NEXT:    ret void
-;
-  %tmp = alloca %fun_t
-  store %fun_t @bar, %fun_t* %tmp
+  %a = alloca i16
+  call void @bar(i16* %a)
   ret void
 }
 
-define internal void @bar(%p_t %p)  {
-; CHECK-LABEL: define {{[^@]+}}@bar()
+define internal void @bar(i16* %p) {
+; CHECK-LABEL: define {{.*}}void @bar()
 ; CHECK-NEXT:    call void @llvm.dbg.value(metadata i16* undef, metadata !3, metadata !DIExpression()), !dbg !5
-; CHECK-NEXT:    ret void
-;
-  call void @llvm.dbg.value(metadata %p_t %p, metadata !4, metadata !5), !dbg !6
-  ret void
-}
-
-declare void @llvm.dbg.value(metadata, metadata, metadata)
-
-
-; Test case where the promoted argument has uses in @callee and we need to
-; retain a reference to the original function, because it is stored in @storer.
-define void @storer({i32, i32}* %ptr) {
-; CHECK-LABEL: define {{[^@]+}}@storer
-; CHECK-SAME: ({ i32, i32 }* [[PTR:%.*]])
-; CHECK-NEXT:    ret void
-;
-  %tmp = alloca i32 ({i32, i32}*)*
-  store i32 ({i32, i32}*)* @callee,  i32 ({i32, i32}*)** %tmp
+  call void @llvm.dbg.value(metadata i16* %p, metadata !3, metadata !DIExpression()), !dbg !5
   ret void
 }
 
-define i32 @caller() {
-; CHECK-LABEL: define {{[^@]+}}@caller()
-; CHECK-NEXT:    [[TMP:%.*]] = alloca { i32, i32 }, align 8
-; CHECK-NEXT:    [[F_1:%.*]] = getelementptr { i32, i32 }, { i32, i32 }* [[TMP]], i32 0, i32 1
-; CHECK-NEXT:    store i32 10, i32* [[F_1]], align 4
-; CHECK-NEXT:    [[TMP_IDX:%.*]] = getelementptr { i32, i32 }, { i32, i32 }* [[TMP]], i64 0, i32 1
-; CHECK-NEXT:    [[TMP_IDX_VAL:%.*]] = load i32, i32* [[TMP_IDX]], align 4
-; CHECK-NEXT:    [[RES:%.*]] = call i32 @callee(i32 [[TMP_IDX_VAL]])
-; CHECK-NEXT:    ret i32 [[RES]]
-;
-  %tmp = alloca {i32, i32}
-  %f.1 = getelementptr {i32, i32}, {i32, i32}* %tmp, i32 0, i32 1
-  store i32 10, i32* %f.1
-  %res = call i32 @callee({i32, i32}* %tmp)
-  ret i32 %res
-}
-
-define internal i32 @callee({i32, i32}* %ptr)  !dbg !7 {
-; CHECK-LABEL: define {{[^@]+}}@callee
-; CHECK-SAME: (i32 [[PTR_0_1_VAL:%.*]]) !dbg !6
-; CHECK-NEXT:    call void @llvm.dbg.value(metadata { i32, i32 }* undef, metadata !7, metadata !DIExpression()), !dbg !8
-; CHECK-NEXT:    call void @llvm.dbg.value(metadata i32 [[PTR_0_1_VAL]], metadata !7, metadata !DIExpression()), !dbg !8
-; CHECK-NEXT:    ret i32 [[PTR_0_1_VAL]]
-;
-  call void @llvm.dbg.value(metadata {i32, i32}* %ptr, metadata !8, metadata !9), !dbg !10
-  %f.1 = getelementptr {i32, i32}, {i32, i32}* %ptr, i32 0, i32 1
-  %l.1 = load i32, i32* %f.1
-  call void @llvm.dbg.value(metadata i32 %l.1, metadata !8, metadata !9), !dbg !10
-  ret i32 %l.1
-}
-
+declare void @llvm.dbg.value(metadata, metadata, metadata) #0
 
+attributes #0 = { nofree nosync nounwind readnone speculatable willreturn }
 
 !llvm.dbg.cu = !{!0}
 !llvm.module.flags = !{!2}
 
-!0 = distinct !DICompileUnit(language: DW_LANG_C, file: !1)
+!0 = distinct !DICompileUnit(language: DW_LANG_C, file: !1, isOptimized: false, runtimeVersion: 0, emissionKind: NoDebug)
 !1 = !DIFile(filename: "test.c", directory: "")
 !2 = !{i32 2, !"Debug Info Version", i32 3}
-!3 = distinct !DISubprogram(name: "bar", unit: !0)
-!4 = !DILocalVariable(name: "p", scope: !3)
-!5 = !DIExpression()
-!6 = !DILocation(line: 1, column: 1, scope: !3)
-!7 = distinct !DISubprogram(name: "callee", unit: !0)
-!8 = !DILocalVariable(name: "c", scope: !7)
-!9 = !DIExpression()
-!10 = !DILocation(line: 2, column: 2, scope: !7)
+!3 = !DILocalVariable(name: "p", scope: !4)
+!4 = distinct !DISubprogram(name: "bar", scope: null, spFlags: DISPFlagDefinition, unit: !0)
+!5 = !DILocation(line: 1, column: 1, scope: !4)