; RUN: llc -mtriple=x86_64-unknown-linux-gnu -relocation-model=pic < %s | FileCheck %s ; RUN: llc -mtriple=x86_64-freebsd -relocation-model=pic < %s | FileCheck %s ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; According to x86-64 psABI, xmm0-xmm7 can be used to pass function parameters. ;; However regcall calling convention uses also xmm8-xmm15 to pass function ;; parameters which violates x86-64 psABI. ;; Detail info about it can be found at: ;; https://sourceware.org/bugzilla/show_bug.cgi?id=21265 ;; ;; We encounter the violation symptom when using PIC with lazy binding ;; optimization. ;; In that case the PLT mechanism as described in x86_64 psABI will ;; not preserve xmm8-xmm15 registers and will lead to miscompilation. ;; ;; The agreed solution is to disable PLT for regcall calling convention for ;; SystemV using ELF format. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; declare void @lazy() declare x86_regcallcc void @regcall_not_lazy() ; CHECK-LABEL: foo: ; CHECK: callq lazy@PLT ; CHECK: callq *regcall_not_lazy@GOTPCREL(%rip) define void @foo() nounwind { call void @lazy() call void @regcall_not_lazy() ret void } ; CHECK-LABEL: tail_call_regcall: ; CHECK: jmpq *regcall_not_lazy@GOTPCREL(%rip) define void @tail_call_regcall() nounwind { tail call void @regcall_not_lazy() ret void } ; CHECK-LABEL: tail_call_regular: ; CHECK: jmp lazy define void @tail_call_regular() nounwind { tail call void @lazy() ret void }