# RUN: llc -run-pass regallocfast %s -o - | FileCheck %s # This test examines register allocation and spilling with Fast Register # Allocator. The test uses inline assembler that requests an input variable to # be loaded in a high register but at the same time has r12 marked as clobbered. # The allocator initially satisfies the load request by selecting r12 but then # needs to spill this register when it reaches the INLINEASM instruction and # notices its clobber definition. # # The test checks that the compiler is able to spill a register from the hGPR # class in Thumb2 by inserting the t2STRi12/t2LDRi12 instructions. --- | ; ModuleID = 'test.ll' source_filename = "test.c" target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64" target triple = "thumbv7m-none-unknown-eabi" define dso_local void @constraint_h() { entry: %i = alloca i32, align 4 %0 = load i32, i32* %i, align 4 call void asm sideeffect "@ $0", "h,~{r12}"(i32 %0) ret void } ... --- name: constraint_h tracksRegLiveness: true registers: - { id: 0, class: hgpr } - { id: 1, class: tgpr } stack: - { id: 0, name: i, size: 4, alignment: 4, stack-id: default, local-offset: -4 } body: | bb.0.entry: %1:tgpr = tLDRspi %stack.0.i, 0, 14, $noreg :: (dereferenceable load 4 from %ir.i) %0:hgpr = COPY %1 INLINEASM &"@ $0", 1, 589833, %0, 12, implicit-def early-clobber $r12 tBX_RET 14, $noreg ... # CHECK: bb.0.entry: # CHECK-NEXT: renamable $r0 = tLDRspi %stack.0.i, 0, 14, $noreg :: (dereferenceable load 4 from %ir.i) # CHECK-NEXT: renamable $r12 = COPY killed renamable $r0 # CHECK-NEXT: t2STRi12 killed $r12, %stack.1, 0, 14, $noreg :: (store 4 into %stack.1) # CHECK-NEXT: $r8 = t2LDRi12 %stack.1, 0, 14, $noreg :: (load 4 from %stack.1) # CHECK-NEXT: INLINEASM &"@ $0", 1, 589833, renamable $r8, 12, implicit-def early-clobber $r12 # CHECK-NEXT: tBX_RET 14, $noreg