incorrect inlining of target function

[ZuseZ4]

rust/compiler/rustc_codegen_llvm/src/back/write.rs

Line 493 in 5e78b0e

let result = llvm::LLVMRustOptimizeWithNewPassManager(

@bytesnake Here we break main trough inlining.
Before:

      8 ; Function Attrs: nonlazybind uwtable
      9 define internal void @_ZN3ref4main17hd7a078464f06f560E() unnamed_addr #2 {
     10   %1 = alloca float, align 4
     11   %2 = alloca float, align 4
     12   %3 = bitcast float* %2 to i8*                                                                                                                                                           13   call void @llvm.lifetime.start.p0i8(i64 4, i8* %3)
     14   store float 0x40091EB860000000, float* %2, align 4
     15   %4 = bitcast float* %1 to i8*
     16   call void @llvm.lifetime.start.p0i8(i64 4, i8* %4)
     17   store float 0.000000e+00, float* %1, align 4
     18   call void @_ZN3ref7cos_ref17h6719ec9878d14346E(float* noalias noundef readonly align 4 dereferenceable(4) %2, float* noalias noundef align 4 dereferenceable(4) %1, float 1.000000e        +00)
     19   br label %5 
     20  
     21 5:                                                ; preds = %0
     22   %6 = load float, float* %1, align 4
     23   %7 = load float, float* %2, align 4
     24   %8 = call float @"_ZN3std3f3221_$LT$impl$u20$f32$GT$3cos17h814fb01877381cc3E"(float %7)
     25   br label %9
     26 
     27 9:                                                ; preds = %5
     28   %10 = fcmp oeq float %6, %8
     29   %11 = xor i1 %10, true
     30   br i1 %11, label %15, label %12
     31 
     32 12:                                               ; preds = %9
     33   %13 = bitcast float* %1 to i8*
     34   call void @llvm.lifetime.end.p0i8(i64 4, i8* %13)
     35   %14 = bitcast float* %2 to i8*
     36   call void @llvm.lifetime.end.p0i8(i64 4, i8* %14)
     37   ret void
     38 
     39 15:                                               ; preds = %9
     40   call void @_ZN4core9panicking5panic17h53e5711e5a6f3ca2E([0 x i8]* noalias noundef nonnull readonly align 1 bitcast (<{ [38 x i8] }>* @3 to [0 x i8]*), i64 38, %0* noalias noundef         readonly align 8 dereferenceable(24) bitcast (<{ i8*, [16 x i8] }>* @4 to %0*)) #7
     41   unreachable
     42 }

After:

      2 ; Function Attrs: nonlazybind uwtable
      3 define internal void @_ZN3ref4main17hd7a078464f06f560E() unnamed_addr #2 {
      4   %1 = alloca float, align 4
      5   %2 = bitcast float* %1 to i8*
      6   call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull %2)  
      7   store float 0x40091EB860000000, float* %1, align 4
      8   call void @_ZN3ref7cos_ref17h6719ec9878d14346E(float* noalias noundef nonnull readonly align 4 dereferenceable(4) %1, float* noalias align 4 undef, float undef)
      9   unreachable
     10 }