[WinEH] Add test for llvm.va.start in catchpad

It already works, but we should have a test for it.

This used to be PR23094 in the old model.

llvm-svn: 250936

llvm/test/CodeGen/X86/win-catchpad-varargs.ll

@@ -0,0 +1,103 @@
+; RUN: llc -mtriple=x86_64-windows-msvc < %s | FileCheck %s --check-prefix=X64
+; RUN: llc -mtriple=i686-windows-msvc < %s | FileCheck %s --check-prefix=X86
+
+declare void @llvm.va_start(i8*)
+declare void @llvm.va_end(i8*)
+declare i32 @__CxxFrameHandler3(...)
+declare void @g()
+
+define i32 @f(i32 %a, ...) personality i32 (...)* @__CxxFrameHandler3 {
+entry:
+  %ap = alloca i8*
+  invoke void @g()
+          to label %return unwind label %catch.dispatch
+
+catch.dispatch:                                   ; preds = %entry
+  %0 = catchpad [i8* null, i32 64, i8* null]
+          to label %catch unwind label %catchendblock
+
+catch:                                            ; preds = %catch.dispatch
+  %ap1 = bitcast i8** %ap to i8*
+  call void @llvm.va_start(i8* %ap1)
+  %argp.cur = load i8*, i8** %ap
+  %1 = bitcast i8* %argp.cur to i32*
+  %arg2 = load i32, i32* %1
+  call void @llvm.va_end(i8* %ap1)
+  catchret %0 to label %return
+
+catchendblock:                                    ; preds = %catch.dispatch
+  catchendpad unwind to caller
+
+return:                                           ; preds = %entry, %catch
+  %retval.0 = phi i32 [ %arg2, %catch ], [ -1, %entry ]
+  ret i32 %retval.0
+}
+
+; X64-LABEL: .seh_proc f
+; X64: pushq %rbp
+; X64: pushq %rsi
+; X64: subq $56, %rsp
+; X64: leaq 48(%rsp), %rbp
+; X64: callq g
+; X64: movl %esi, %eax
+; X64: addq $56, %rsp
+; X64: popq %rsi
+; X64: popq %rbp
+
+; X64: movl 4(%rbp), %esi
+; X64: jmp
+
+; X64-LABEL: "?catch$1@?0?f@4HA":
+; X64: .seh_proc "?catch$1@?0?f@4HA"
+; X64:         movq    %rdx, 16(%rsp)
+; X64:         pushq   %rbp
+; X64:         pushq   %rsi
+; X64:         subq    $40, %rsp
+; X64:         leaq    48(%rdx), %rbp
+; arg2 is at RBP+40:
+; start at arg2
+; + 8 for arg1
+; + 8 for retaddr
+; + 8 for RBP
+; + 8 for RSI
+; + 56 for stackalloc
+; - 48 for setframe
+; = 40
+; X64:         movl    40(%rbp), %eax
+; X64:         movl    %eax, 4(%rbp)
+; X64:         leaq    .LBB0_2(%rip), %rax
+; X64:         addq    $40, %rsp
+; X64: 	       popq    %rsi
+; X64:         popq    %rbp
+; X64:         retq                            # CATCHRET
+
+; X86-LABEL: _f:                                     # @f
+; X86:         pushl   %ebp
+; X86:         movl    %esp, %ebp
+; X86:         pushl   %ebx
+; X86:         pushl   %edi
+; X86:         pushl   %esi
+; X86:         subl    $28, %esp
+; X86: 	       movl    $-1, -40(%ebp)
+; X86:         calll   _g
+; X86:         movl    -40(%ebp), %eax
+; X86:         addl    $28, %esp
+; X86:         popl    %esi
+; X86:         popl    %edi
+; X86:         popl    %ebx
+; X86:         popl    %ebp
+; X86:         retl
+
+; X86-LABEL: "?catch$1@?0?f@4HA":
+; X86:         pushl   %ebp
+; X86:         addl    $12, %ebp
+; arg2 is at EBP offset 12:
+; + 4 for arg1
+; + 4 for retaddr
+; + 4 for EBP
+; Done due to mov %esp, %ebp
+; X86:         movl    12(%ebp), %eax
+; X86:         movl    %eax, -32(%ebp)
+; X86:         movl    $LBB0_2, %eax
+; X86:         popl    %ebp
+; X86:         retl                            # CATCHRET