Version-gate usage of LLVM.PassBuilder

The newPM is not available until Julia 1.10. Unfortunately, this does
mean that we use a slightly different pipeline for Julia 1.9, but at
least it gets things working for now.

src/AllocCheck.jl

@@ -105,21 +105,25 @@ function backtrace_(inst::LLVM.Instruction, bt=StackTraces.StackFrame[]; compile
     return bt
 end
 
-function build_newpm_pipeline!(pb::PassBuilder, mpm::NewPMModulePassManager, speedup=2, size=0, lower_intrinsic=true,
-    dump_native=false, external_use=false, llvm_only=false,)
-    ccall(:jl_build_newpm_pipeline, Cvoid, (LLVM.API.LLVMModulePassManagerRef, LLVM.API.LLVMPassBuilderRef, Cint, Cint, Cint, Cint, Cint, Cint),
-        mpm, pb, speedup, size, lower_intrinsic, dump_native, external_use, llvm_only)
-end
+if LLVM.has_newpm() && VERSION >= v"1.10.0-DEV.1622"
+    function build_newpm_pipeline!(pb::PassBuilder, mpm::NewPMModulePassManager, speedup=2, size=0, lower_intrinsic=true,
+        dump_native=false, external_use=false, llvm_only=false,)
+        ccall(:jl_build_newpm_pipeline, Cvoid, (LLVM.API.LLVMModulePassManagerRef, LLVM.API.LLVMPassBuilderRef, Cint, Cint, Cint, Cint, Cint, Cint),
+            mpm, pb, speedup, size, lower_intrinsic, dump_native, external_use, llvm_only)
+    end
 
-function optimize!(@nospecialize(job::CompilerJob), mod::LLVM.Module)
-    triple = GPUCompiler.llvm_triple(job.config.target)
-    tm = GPUCompiler.llvm_machine(job.config.target)
-    @dispose pb = LLVM.PassBuilder(tm) begin
-        @dispose mpm = LLVM.NewPMModulePassManager(pb) begin
-            build_newpm_pipeline!(pb, mpm)
-            run!(mpm, mod, tm)
+    function optimize!(@nospecialize(job::CompilerJob), mod::LLVM.Module)
+        triple = GPUCompiler.llvm_triple(job.config.target)
+        tm = GPUCompiler.llvm_machine(job.config.target)
+        @dispose pb = LLVM.PassBuilder(tm) begin
+            @dispose mpm = LLVM.NewPMModulePassManager(pb) begin
+                build_newpm_pipeline!(pb, mpm)
+                run!(mpm, mod, tm)
+            end
         end
     end
+else
+    optimize!(@nospecialize(job::CompilerJob), mod::LLVM.Module) = GPUCompiler.compile(:llvm, job, validate=false)
 end
 
 struct AllocInstance