[Sparc] Check register use with isPhysRegUsed() instead of reg_nodbg_empty()
Summary: By using reg_nodbg_empty() to determine if a function can be
treated as a leaf function or not, we miss the case when the register
pair L0_L1 is used but not L0 by itself. This has the effect that
use_all_i32_regs(), a test in reserved-regs.ll which tries to use all
registers, gets treated as a leaf function.
Reviewers: jyknight, venkatra
Reviewed By: jyknight
Subscribers: davide, RKSimon, sepavloff, llvm-commits
Differential Revision: https://reviews.llvm.org/D27089
llvm-svn: 297285
diff --git a/llvm/lib/Target/Sparc/SparcFrameLowering.cpp b/llvm/lib/Target/Sparc/SparcFrameLowering.cpp
index 122f830..c07cc21 100644
--- a/llvm/lib/Target/Sparc/SparcFrameLowering.cpp
+++ b/llvm/lib/Target/Sparc/SparcFrameLowering.cpp
@@ -288,11 +288,11 @@
{
for (unsigned reg = SP::I0; reg <= SP::I7; ++reg)
- if (!MRI->reg_nodbg_empty(reg))
+ if (MRI->isPhysRegUsed(reg))
return false;
for (unsigned reg = SP::L0; reg <= SP::L7; ++reg)
- if (!MRI->reg_nodbg_empty(reg))
+ if (MRI->isPhysRegUsed(reg))
return false;
return true;
@@ -305,8 +305,8 @@
MachineFrameInfo &MFI = MF.getFrameInfo();
return !(MFI.hasCalls() // has calls
- || !MRI.reg_nodbg_empty(SP::L0) // Too many registers needed
- || !MRI.reg_nodbg_empty(SP::O6) // %SP is used
+ || MRI.isPhysRegUsed(SP::L0) // Too many registers needed
+ || MRI.isPhysRegUsed(SP::O6) // %SP is used
|| hasFP(MF)); // need %FP
}
@@ -314,11 +314,10 @@
MachineRegisterInfo &MRI = MF.getRegInfo();
// Remap %i[0-7] to %o[0-7].
for (unsigned reg = SP::I0; reg <= SP::I7; ++reg) {
- if (MRI.reg_nodbg_empty(reg))
+ if (!MRI.isPhysRegUsed(reg))
continue;
unsigned mapped_reg = reg - SP::I0 + SP::O0;
- assert(MRI.reg_nodbg_empty(mapped_reg));
// Replace I register with O register.
MRI.replaceRegWith(reg, mapped_reg);