Reuse gcframe for jlcall

[yuyichao]

jlcall is not using gcframe anymore after #21888 . With

julia> @noinline g2(a...) = a[1][]
g2 (generic function with 1 method)

julia> f2() = g2(Ref(1))
f2 (generic function with 1 method)

code_llvm

define i64 @julia_f2_63184() #0 !dbg !5 {
top:
  %0 = alloca [2 x %jl_value_t addrspace(10)*], align 8
  %gcframe2 = alloca [4 x %jl_value_t addrspace(10)*], align 8
  %gcframe2.sub = getelementptr inbounds [4 x %jl_value_t addrspace(10)*], [4 x %jl_value_t addrspace(10)*]* %gcframe2, i64 0, i64 0
  %.sub = getelementptr inbounds [2 x %jl_value_t addrspace(10)*], [2 x %jl_value_t addrspace(10)*]* %0, i64 0, i64 0
  %gcroot1 = getelementptr inbounds [4 x %jl_value_t addrspace(10)*], [4 x %jl_value_t addrspace(10)*]* %gcframe2, i64 0, i64 2
  %1 = getelementptr inbounds [4 x %jl_value_t addrspace(10)*], [4 x %jl_value_t addrspace(10)*]* %gcframe2, i64 0, i64 1
  %2 = bitcast %jl_value_t addrspace(10)** %1 to i8*
  call void @llvm.memset.p0i8.i32(i8* %2, i8 0, i32 24, i32 8, i1 false)
  %ptls_i8 = call i8* asm "movq %fs:0, $0;\0Aaddq $$-10928, $0", "=r,~{dirflag},~{fpsr},~{flags}"() #2
  %3 = bitcast [4 x %jl_value_t addrspace(10)*]* %gcframe2 to i64*
  store i64 4, i64* %3, align 8
  %4 = getelementptr inbounds [4 x %jl_value_t addrspace(10)*], [4 x %jl_value_t addrspace(10)*]* %gcframe2, i64 0, i64 1
  %5 = bitcast i8* %ptls_i8 to i64*
  %6 = load i64, i64* %5, align 8
  %7 = bitcast %jl_value_t addrspace(10)** %4 to i64*
  store i64 %6, i64* %7, align 8
  %8 = bitcast i8* %ptls_i8 to %jl_value_t addrspace(10)***
  store %jl_value_t addrspace(10)** %gcframe2.sub, %jl_value_t addrspace(10)*** %8, align 8
  %9 = call %jl_value_t addrspace(10)* @jl_gc_pool_alloc(i8* %ptls_i8, i32 1432, i32 16)
  %10 = addrspacecast %jl_value_t addrspace(10)* %9 to %jl_value_t addrspace(11)*
  %11 = bitcast %jl_value_t addrspace(11)* %10 to %jl_value_t addrspace(10)* addrspace(11)*
  %12 = getelementptr %jl_value_t addrspace(10)*, %jl_value_t addrspace(10)* addrspace(11)* %11, i64 -1
  store %jl_value_t addrspace(10)* addrspacecast (%jl_value_t* inttoptr (i64 140124422927792 to %jl_value_t*) to %jl_value_t addrspace(10)*), %jl_value_t addrspace(10)* addrspace(11)* %12, align 8
  %13 = bitcast %jl_value_t addrspace(10)* %9 to i64 addrspace(10)*
  %14 = addrspacecast i64 addrspace(10)* %13 to i64 addrspace(11)*
  store i64 1, i64 addrspace(11)* %14, align 16
  %15 = getelementptr inbounds [4 x %jl_value_t addrspace(10)*], [4 x %jl_value_t addrspace(10)*]* %gcframe2, i64 0, i64 3
  store %jl_value_t addrspace(10)* %9, %jl_value_t addrspace(10)** %15, align 8
  store %jl_value_t addrspace(10)* addrspacecast (%jl_value_t* inttoptr (i64 140124422078488 to %jl_value_t*) to %jl_value_t addrspace(10)*), %jl_value_t addrspace(10)** %.sub, align 8
  %16 = getelementptr inbounds [2 x %jl_value_t addrspace(10)*], [2 x %jl_value_t addrspace(10)*]* %0, i64 0, i64 1
  store %jl_value_t addrspace(10)* %9, %jl_value_t addrspace(10)** %16, align 8
  %17 = call %jl_value_t addrspace(10)* @jl_invoke(%jl_value_t addrspace(10)* addrspacecast (%jl_value_t* inttoptr (i64 140123895890192 to %jl_value_t*) to %jl_value_t addrspace(10)*), %jl_value_t addrspace(10)** %.sub, i32 2)
  store %jl_value_t addrspace(10)* %17, %jl_value_t addrspace(10)** %gcroot1, align 8
  store %jl_value_t addrspace(10)* %17, %jl_value_t addrspace(10)** %15, align 8
  %18 = bitcast %jl_value_t addrspace(10)* %17 to i64 addrspace(10)*
  %19 = load i64, i64 addrspace(10)* %18, align 16
  %20 = load %jl_value_t addrspace(10)*, %jl_value_t addrspace(10)** %4, align 8
  %21 = bitcast i8* %ptls_i8 to %jl_value_t addrspace(10)**
  store %jl_value_t addrspace(10)* %20, %jl_value_t addrspace(10)** %21, align 8
  ret i64 %19
}

Two alloca are created for jlcall and gcframe separately.

%0 = alloca [2 x %jl_value_t addrspace(10)*], align 8
%gcframe2 = alloca [4 x %jl_value_t addrspace(10)*], align 8

This could be related to #14779 (which means that the gcframe content could change after a jlcall)