diff options
| author | Hal Finkel <hfinkel@anl.gov> | 2013-03-19 08:09:38 +0000 |
|---|---|---|
| committer | Hal Finkel <hfinkel@anl.gov> | 2013-03-19 08:09:38 +0000 |
| commit | 54e57f8cb79bdc23ed8289cf2a558fa7c9602972 (patch) | |
| tree | df7ed3c8fb6d2fd5d6e7bf7f7340a16e5b7dad22 | |
| parent | d37c8568e68d0ea3492503cd192783900e2d922a (diff) | |
Don't reserve R31 on PPC64 unless the frame pointer is needed
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177379 91177308-0d34-0410-b5e6-96231b3b80d8
| -rw-r--r-- | lib/Target/PowerPC/PPCRegisterInfo.cpp | 7 | ||||
| -rw-r--r-- | test/CodeGen/PowerPC/r31.ll | 15 |
2 files changed, 18 insertions, 4 deletions
diff --git a/lib/Target/PowerPC/PPCRegisterInfo.cpp b/lib/Target/PowerPC/PPCRegisterInfo.cpp index e2c7221be3..74261a3a50 100644 --- a/lib/Target/PowerPC/PPCRegisterInfo.cpp +++ b/lib/Target/PowerPC/PPCRegisterInfo.cpp @@ -117,16 +117,15 @@ BitVector PPCRegisterInfo::getReservedRegs(const MachineFunction &MF) const { } // On PPC64, r13 is the thread pointer. Never allocate this register. - // Note that this is over conservative, as it also prevents allocation of R31 - // when the FP is not needed. if (Subtarget.isPPC64()) { Reserved.set(PPC::R13); - Reserved.set(PPC::R31); Reserved.set(PPC::X0); Reserved.set(PPC::X1); Reserved.set(PPC::X13); - Reserved.set(PPC::X31); + + if (PPCFI->needsFP(MF)) + Reserved.set(PPC::X31); // The 64-bit SVR4 ABI reserves r2 for the TOC pointer. if (Subtarget.isSVR4ABI()) { diff --git a/test/CodeGen/PowerPC/r31.ll b/test/CodeGen/PowerPC/r31.ll new file mode 100644 index 0000000000..7ce12f600b --- /dev/null +++ b/test/CodeGen/PowerPC/r31.ll @@ -0,0 +1,15 @@ +; RUN: llc < %s -mtriple=powerpc64-unknown-linux-gnu -mcpu=g4 | FileCheck %s +target datalayout = "E-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f128:64:128-n32" + +define i64 @foo(i64 %a) nounwind { +entry: + call void asm sideeffect "", "~{r0},~{r3},~{r4},~{r5},~{r6},~{r7},~{r8},~{r9},~{r10},~{r11},~{r12},~{r14},~{r15},~{r16},~{r17},~{r18},~{r19},~{r20},~{r21},~{r22},~{r23},~{r24},~{r25},~{r26},~{r27},~{r28},~{r29},~{r30}"() nounwind + br label %return + +; CHECK: @foo +; CHECK: mr 31, 3 + +return: ; preds = %entry + ret i64 %a +} + |