Add an option to use a virtual register as the global base register instead of
reserving a physical register ($gp or $28) for that purpose.
This will completely eliminate loads that restore the value of $gp after every
function call, if the register allocator assigns a callee-saved register, or
eliminate unnecessary loads if it assigns a temporary register.
example:
.cpload $25 // set $gp.
...
.cprestore 16 // store $gp to stack slot 16($sp).
...
jalr $25 // function call. clobbers $gp.
lw $gp, 16($sp) // not emitted if callee-saved reg is chosen.
...
lw $2, 4($gp)
...
jalr $25 // function call.
lw $gp, 16($sp) // not emitted if $gp is not live after this instruction.
...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151402 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsTargetMachine.cpp b/lib/Target/Mips/MipsTargetMachine.cpp
index ff766fa..8806aaf 100644
--- a/lib/Target/Mips/MipsTargetMachine.cpp
+++ b/lib/Target/Mips/MipsTargetMachine.cpp
@@ -106,7 +106,7 @@
virtual bool addInstSelector();
virtual bool addPreRegAlloc();
- virtual bool addPostRegAlloc();
+ virtual bool addPreSched2();
virtual bool addPreEmitPass();
};
} // namespace
@@ -140,7 +140,7 @@
return true;
}
-bool MipsPassConfig::addPostRegAlloc() {
+bool MipsPassConfig::addPreSched2() {
PM.add(createMipsExpandPseudoPass(getMipsTargetMachine()));
return true;
}