In x64/printGcc, fix gcc printing of 64-bit constants and mul
In x64/printGcc, fix gcc printing of 64-bit constants and mul

briangmilnes/vale,project-everest/vale,briangmilnes/vale,briangmilnes/vale,briangmilnes/vale,project-everest/vale,project-everest/vale,project-everest/vale