[AArch64] Allow access to all system registers with MRS/MSR instructions.
The A64 instruction set includes a generic register syntax for accessing
implementation-defined system registers. The syntax for these registers is:
S<op0>_<op1>_<CRn>_<CRm>_<op2>
The encoding space permitted for implementation-defined system registers
is:
op0 op1 CRn CRm op2
11 xxx 1x11 xxxx xxx
The full encoding space can now be accessed:
op0 op1 CRn CRm op2
xx xxx xxxx xxxx xxx
This is useful to anyone needing to write assembly code supporting new
system registers before the assembler has learned the official names for
them.
llvm-svn: 218753
diff --git a/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp b/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp
index 3c24bb3..bc6c7a9 100644
--- a/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp
+++ b/llvm/lib/Target/AArch64/Utils/AArch64BaseInfo.cpp
@@ -791,22 +791,22 @@
}
}
- // Try to parse an S<op0>_<op1>_<Cn>_<Cm>_<op2> register name, where the bits
- // are: 11 xxx 1x11 xxxx xxx
- Regex GenericRegPattern("^s3_([0-7])_c(1[15])_c([0-9]|1[0-5])_([0-7])$");
+ // Try to parse an S<op0>_<op1>_<Cn>_<Cm>_<op2> register name
+ Regex GenericRegPattern("^s([0-3])_([0-7])_c([0-9]|1[0-5])_c([0-9]|1[0-5])_([0-7])$");
- SmallVector<StringRef, 4> Ops;
+ SmallVector<StringRef, 5> Ops;
if (!GenericRegPattern.match(NameLower, &Ops)) {
Valid = false;
return -1;
}
- uint32_t Op0 = 3, Op1 = 0, CRn = 0, CRm = 0, Op2 = 0;
+ uint32_t Op0 = 0, Op1 = 0, CRn = 0, CRm = 0, Op2 = 0;
uint32_t Bits;
- Ops[1].getAsInteger(10, Op1);
- Ops[2].getAsInteger(10, CRn);
- Ops[3].getAsInteger(10, CRm);
- Ops[4].getAsInteger(10, Op2);
+ Ops[1].getAsInteger(10, Op0);
+ Ops[2].getAsInteger(10, Op1);
+ Ops[3].getAsInteger(10, CRn);
+ Ops[4].getAsInteger(10, CRm);
+ Ops[5].getAsInteger(10, Op2);
Bits = (Op0 << 14) | (Op1 << 11) | (CRn << 7) | (CRm << 3) | Op2;
Valid = true;
@@ -814,11 +814,10 @@
}
std::string
-AArch64SysReg::SysRegMapper::toString(uint32_t Bits, bool &Valid) const {
+AArch64SysReg::SysRegMapper::toString(uint32_t Bits) const {
// First search the registers shared by all
for (unsigned i = 0; i < array_lengthof(SysRegPairs); ++i) {
if (SysRegPairs[i].Value == Bits) {
- Valid = true;
return SysRegPairs[i].Name;
}
}
@@ -827,7 +826,6 @@
if (FeatureBits & AArch64::ProcCyclone) {
for (unsigned i = 0; i < array_lengthof(CycloneSysRegPairs); ++i) {
if (CycloneSysRegPairs[i].Value == Bits) {
- Valid = true;
return CycloneSysRegPairs[i].Name;
}
}
@@ -837,28 +835,18 @@
// write-only).
for (unsigned i = 0; i < NumInstPairs; ++i) {
if (InstPairs[i].Value == Bits) {
- Valid = true;
return InstPairs[i].Name;
}
}
+ assert(Bits < 0x10000);
uint32_t Op0 = (Bits >> 14) & 0x3;
uint32_t Op1 = (Bits >> 11) & 0x7;
uint32_t CRn = (Bits >> 7) & 0xf;
uint32_t CRm = (Bits >> 3) & 0xf;
uint32_t Op2 = Bits & 0x7;
- // Only combinations matching: 11 xxx 1x11 xxxx xxx are valid for a generic
- // name.
- if (Op0 != 3 || (CRn != 11 && CRn != 15)) {
- Valid = false;
- return "";
- }
-
- assert(Op0 == 3 && (CRn == 11 || CRn == 15) && "Invalid generic sysreg");
-
- Valid = true;
- return "s3_" + utostr(Op1) + "_c" + utostr(CRn)
+ return "s" + utostr(Op0)+ "_" + utostr(Op1) + "_c" + utostr(CRn)
+ "_c" + utostr(CRm) + "_" + utostr(Op2);
}