Report error when finding variadic function other than printf (#2703)

Variadic functions are not supported in SPIR-V, the only known exception is printf.

Signed-off-by: Marcos Maronas <[email protected]>

Original commit:
KhronosGroup/SPIRV-LLVM-Translator@569972a61c86aa6

Author: maarquitos14

llvm-spirv/lib/SPIRV/SPIRVWriter.cpp

@@ -835,6 +835,18 @@ SPIRVType *LLVMToSPIRVBase::transSPIRVOpaqueType(StringRef STName,
 SPIRVType *LLVMToSPIRVBase::transScavengedType(Value *V) {
   if (auto *F = dyn_cast<Function>(V)) {
     FunctionType *FnTy = Scavenger->getFunctionType(F);
+    // VarArg functions other than printf are not supported in SPIR-V. None of
+    // printf variants can actually reach this point because they're skipped in
+    // 'LLVMToSPIRVBase::translate()'. Specifically,
+    // 'isBuiltinTransToExtInst(&F)' returns true for printf and its variants,
+    // and so they are never added to 'Decls' and 'Defs'. Therefore, it's safe
+    // to only check here if we're dealing with a variadic function to report an
+    // error. To be on the safe side, an assertion is added to check printf
+    // never reaches this point.
+    assert(F->getName() != "printf");
+    BM->getErrorLog().checkError(!FnTy->isVarArg(),
+                                 SPIRVEC_UnsupportedVarArgFunction);
+
     SPIRVType *RT = transType(FnTy->getReturnType());
     std::vector<SPIRVType *> PT;
     for (Argument &Arg : F->args()) {

llvm-spirv/lib/SPIRV/libSPIRV/SPIRVErrorEnum.h

@@ -29,6 +29,8 @@ _SPIRV_OP(InvalidVersionNumber,
           "Invalid Version Number.")
 _SPIRV_OP(UnspecifiedMemoryModel, "Unspecified Memory Model.")
 _SPIRV_OP(RepeatedMemoryModel, "Expects a single OpMemoryModel instruction.")
+_SPIRV_OP(UnsupportedVarArgFunction,
+          "Variadic functions other than 'printf' are not supported in SPIR-V.")
 
 /* This is the last error code to have a maximum valid value to compare to */
 _SPIRV_OP(InternalMaxErrorCode, "Unknown error code")

llvm-spirv/test/DebugInfo/Generic/2009-11-10-CurrentFn.ll

@@ -9,11 +9,11 @@ target triple = "spir64-unknown-unknown"
 
 define void @bar(i32 %i) nounwind uwtable ssp !dbg !5 {
 entry:
-  tail call void (...) @foo() nounwind, !dbg !14
+  tail call void @foo() nounwind, !dbg !14
   ret void, !dbg !16
 }
 
-declare void @foo(...)
+declare void @foo()
 
 declare void @llvm.dbg.value(metadata, metadata, metadata) nounwind readnone
 

llvm-spirv/test/DebugInfo/Generic/multiline.ll

@@ -49,16 +49,16 @@ target triple = "spir64-unknown-unknown"
 ; Function Attrs: nounwind uwtable
 define void @f2() #0 !dbg !4 {
 entry:
-  call void (...) @f1(), !dbg !11
-  call void (...) @f1(), !dbg !12
-  call void (...) @f1(), !dbg !13
-  call void (...) @f1(), !dbg !14
-  call void (...) @f1(), !dbg !15
-  call void (...) @f1(), !dbg !16
+  call void @f1(), !dbg !11
+  call void @f1(), !dbg !12
+  call void @f1(), !dbg !13
+  call void @f1(), !dbg !14
+  call void @f1(), !dbg !15
+  call void @f1(), !dbg !16
   ret void, !dbg !17
 }
 
-declare void @f1(...) #1
+declare void @f1() #1
 
 attributes #0 = { nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
 attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

llvm-spirv/test/DebugInfo/Generic/varargs.ll

@@ -30,16 +30,16 @@ target triple = "spir64-unknown-unknown"
 ; Function Attrs: alwaysinline nounwind ssp uwtable
 define void @g() #0 !dbg !7 {
 entry:
-  tail call void (...) @f() #3, !dbg !10
+  tail call void @f() #3, !dbg !10
   ret void, !dbg !11
 }
 
-declare void @f(...)
+declare void @f()
 
 ; Function Attrs: nounwind ssp uwtable
 define void @h() #2 !dbg !12 {
 entry:
-  tail call void (...) @f() #3, !dbg !13
+  tail call void @f() #3, !dbg !13
   ret void, !dbg !15
 }
 

llvm-spirv/test/DebugInfo/X86/abstract_origin.ll

@@ -51,7 +51,7 @@ entry:
   call void @llvm.dbg.value(metadata i32 3, metadata !10, metadata !DIExpression()), !dbg !15
   %call = call i32 @f3(i32 3) #3, !dbg !16
   call void @llvm.dbg.value(metadata i32 7, metadata !10, metadata !DIExpression()), !dbg !18
-  %call1 = call i32 (...) @f1() #3, !dbg !19
+  %call1 = call i32 @f1() #3, !dbg !19
   call void @llvm.dbg.value(metadata i32 %call1, metadata !10, metadata !DIExpression()), !dbg !19
   store i32 %call1, ptr %i, align 4, !dbg !19, !tbaa !20
   call void @llvm.dbg.value(metadata ptr %i, metadata !10, metadata !DIExpression(DW_OP_deref)), !dbg !24
@@ -61,7 +61,7 @@ entry:
 
 declare i32 @f3(i32)
 
-declare i32 @f1(...)
+declare i32 @f1()
 
 declare void @f2(ptr)
 

llvm-spirv/test/DebugInfo/X86/dbg-value-const-byref.ll

@@ -46,15 +46,15 @@ target triple = "spir64-unknown-unknown"
 define void @f() #0 !dbg !4 {
 entry:
   tail call void @h(i32 0) #2, !dbg !14
-  %call = tail call i32 (...) @g() #2, !dbg !15
+  %call = tail call i32 @g() #2, !dbg !15
   tail call void @llvm.dbg.value(metadata i32 %call, metadata !8, metadata !16), !dbg !17
   tail call void @h(i32 %call) #2, !dbg !18
   ret void, !dbg !19
 }
 
 declare void @h(i32)
 
-declare i32 @g(...)
+declare i32 @g()
 
 ; Function Attrs: nounwind readnone
 declare void @llvm.dbg.value(metadata, metadata, metadata) #1

llvm-spirv/test/DebugInfo/X86/single-dbg_value.ll

@@ -37,7 +37,7 @@ lpad:
   ret i32 0
 }
 
-declare dso_local i32 @__gxx_personality_v0(...)
+declare dso_local i32 @__gxx_personality_v0()
 
 attributes #0 = { norecurse "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "sycl-module-id"="/localdisk2/icl/fadeeval/sycl_workspace/reproducer2/test.cpp" "uniform-work-group-size"="true" "unsafe-fp-math"="false" "use-soft-float"="false" }
 attributes #1 = { norecurse nounwind readnone "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }

llvm-spirv/test/negative/unsup_invoke_instr.ll

@@ -0,0 +1,17 @@
+; Check whether the translator reports an error for a
+; function other than printf with variadic arguments.
+
+; RUN: llvm-as < %s -o %t.bc
+; RUN: not llvm-spirv %t.bc 2>&1 | FileCheck %s
+
+target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-n8:16:32:64-G1"
+target triple = "spir64-unknown-unknown"
+
+; CHECK: UnsupportedVarArgFunction: Variadic functions other than 'printf' are not supported in SPIR-V.
+; Function Attrs: convergent
+declare spir_func void @for__issue_diagnostic(i32 noundef, i32 noundef, ...) local_unnamed_addr
+
+define i32 @foo() nounwind {
+  call spir_func void (i32, i32, ...) @for__issue_diagnostic(i32 noundef 41, i32 noundef 0)
+  ret i32 0
+}