Rename ARMcmpNZ to ARMcmpZ and use it to represent comparisons that set only the Z flag (i.e. eq and ne). Make ARMcmpZ commutative.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74423 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 53 insertions, 30 deletions

diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index c24bb2e..bf0a56b 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -402,7 +402,7 @@ const char *ARMTargetLowering::getTargetNodeName(unsigned Opcode) const {
   case ARMISD::RET_FLAG:      return "ARMISD::RET_FLAG";
   case ARMISD::PIC_ADD:       return "ARMISD::PIC_ADD";
   case ARMISD::CMP:           return "ARMISD::CMP";
-  case ARMISD::CMPNZ:         return "ARMISD::CMPNZ";
+  case ARMISD::CMPZ:          return "ARMISD::CMPZ";
   case ARMISD::CMPFP:         return "ARMISD::CMPFP";
   case ARMISD::CMPFPw0:       return "ARMISD::CMPFPw0";
   case ARMISD::FMSTAT:        return "ARMISD::FMSTAT";
@@ -1592,10 +1592,8 @@ static SDValue getARMCmp(SDValue LHS, SDValue RHS, ISD::CondCode CC,
     break;
   case ARMCC::EQ:
   case ARMCC::NE:
-  case ARMCC::MI:
-  case ARMCC::PL:
-    // Uses only N and Z Flags
-    CompareType = ARMISD::CMPNZ;
+    // Uses only Z Flag
+    CompareType = ARMISD::CMPZ;
     break;
   }
   ARMCC = DAG.getConstant(CondCode, MVT::i32);
diff --git a/lib/Target/ARM/ARMISelLowering.h b/lib/Target/ARM/ARMISelLowering.h
index 631e37f..c4920e6 100644
--- a/lib/Target/ARM/ARMISelLowering.h
+++ b/lib/Target/ARM/ARMISelLowering.h
@@ -45,7 +45,7 @@ namespace llvm {
       PIC_ADD,      // Add with a PC operand and a PIC label.
 
       CMP,          // ARM compare instructions.
-      CMPNZ,        // ARM compare that uses only N or Z flags.
+      CMPZ,         // ARM compare that sets only Z flag.
       CMPFP,        // ARM VFP compare instruction, sets FPSCR.
       CMPFPw0,      // ARM VFP compare against zero instruction, sets FPSCR.
       FMSTAT,       // ARM fmstat instruction.
diff --git a/lib/Target/ARM/ARMInstrInfo.td b/lib/Target/ARM/ARMInstrInfo.td
index 611cb60..b3f7a7d 100644
--- a/lib/Target/ARM/ARMInstrInfo.td
+++ b/lib/Target/ARM/ARMInstrInfo.td
@@ -75,8 +75,8 @@ def ARMbrjt          : SDNode<"ARMISD::BR_JT", SDT_ARMBrJT,
 def ARMcmp           : SDNode<"ARMISD::CMP", SDT_ARMCmp,
                               [SDNPOutFlag]>;
 
-def ARMcmpNZ         : SDNode<"ARMISD::CMPNZ", SDT_ARMCmp,
-                              [SDNPOutFlag]>;
+def ARMcmpZ          : SDNode<"ARMISD::CMPZ", SDT_ARMCmp,
+                              [SDNPOutFlag,SDNPCommutative]>;
 
 def ARMpic_add       : SDNode<"ARMISD::PIC_ADD", SDT_ARMPICAdd>;
 
@@ -1272,19 +1272,19 @@ defm CMN  : AI1_cmp_irs<0b1011, "cmn",
 
 // Note that TST/TEQ don't set all the same flags that CMP does!
 defm TST  : AI1_cmp_irs<0b1000, "tst",
-                        BinOpFrag<(ARMcmpNZ (and node:$LHS, node:$RHS), 0)>, 1>;
+                        BinOpFrag<(ARMcmpZ (and node:$LHS, node:$RHS), 0)>, 1>;
 defm TEQ  : AI1_cmp_irs<0b1001, "teq",
-                        BinOpFrag<(ARMcmpNZ (xor node:$LHS, node:$RHS), 0)>, 1>;
+                        BinOpFrag<(ARMcmpZ (xor node:$LHS, node:$RHS), 0)>, 1>;
 
-defm CMPnz : AI1_cmp_irs<0b1010, "cmp",
-                         BinOpFrag<(ARMcmpNZ node:$LHS, node:$RHS)>>;
-defm CMNnz : AI1_cmp_irs<0b1011, "cmn",
-                         BinOpFrag<(ARMcmpNZ node:$LHS,(ineg node:$RHS))>>;
+defm CMPz  : AI1_cmp_irs<0b1010, "cmp",
+                         BinOpFrag<(ARMcmpZ node:$LHS, node:$RHS)>>;
+defm CMNz  : AI1_cmp_irs<0b1011, "cmn",
+                         BinOpFrag<(ARMcmpZ node:$LHS,(ineg node:$RHS))>>;
 
 def : ARMPat<(ARMcmp GPR:$src, so_imm_neg:$imm),
              (CMNri  GPR:$src, so_imm_neg:$imm)>;
 
-def : ARMPat<(ARMcmpNZ GPR:$src, so_imm_neg:$imm),
+def : ARMPat<(ARMcmpZ GPR:$src, so_imm_neg:$imm),
              (CMNri  GPR:$src, so_imm_neg:$imm)>;
 
 
diff --git a/lib/Target/ARM/ARMInstrThumb.td b/lib/Target/ARM/ARMInstrThumb.td
index dce0c1d..ae54a88 100644
--- a/lib/Target/ARM/ARMInstrThumb.td
+++ b/lib/Target/ARM/ARMInstrThumb.td
@@ -362,9 +362,9 @@ let Defs = [CPSR] in {
 def tCMN : T1I<(outs), (ins tGPR:$lhs, tGPR:$rhs),
               "cmn $lhs, $rhs",
               [(ARMcmp tGPR:$lhs, (ineg tGPR:$rhs))]>;
-def tCMNNZ : T1I<(outs), (ins tGPR:$lhs, tGPR:$rhs),
-                "cmn $lhs, $rhs",
-                [(ARMcmpNZ tGPR:$lhs, (ineg tGPR:$rhs))]>;
+def tCMNZ : T1I<(outs), (ins tGPR:$lhs, tGPR:$rhs),
+               "cmn $lhs, $rhs",
+               [(ARMcmpZ tGPR:$lhs, (ineg tGPR:$rhs))]>;
 }
 
 // CMP immediate
@@ -372,9 +372,9 @@ let Defs = [CPSR] in {
 def tCMPi8 : T1I<(outs), (ins tGPR:$lhs, i32imm:$rhs),
                "cmp $lhs, $rhs",
                [(ARMcmp tGPR:$lhs, imm0_255:$rhs)]>;
-def tCMPNZi8 : T1I<(outs), (ins tGPR:$lhs, i32imm:$rhs),
-                 "cmp $lhs, $rhs",
-                 [(ARMcmpNZ tGPR:$lhs, imm0_255:$rhs)]>;
+def tCMPZi8 : T1I<(outs), (ins tGPR:$lhs, i32imm:$rhs),
+                "cmp $lhs, $rhs",
+                [(ARMcmpZ tGPR:$lhs, imm0_255:$rhs)]>;
 
 }
 
@@ -383,9 +383,9 @@ let Defs = [CPSR] in {
 def tCMPr : T1I<(outs), (ins tGPR:$lhs, tGPR:$rhs),
                "cmp $lhs, $rhs",
                [(ARMcmp tGPR:$lhs, tGPR:$rhs)]>;
-def tCMPNZr : T1I<(outs), (ins tGPR:$lhs, tGPR:$rhs),
-                 "cmp $lhs, $rhs",
-                 [(ARMcmpNZ tGPR:$lhs, tGPR:$rhs)]>;
+def tCMPZr : T1I<(outs), (ins tGPR:$lhs, tGPR:$rhs),
+                "cmp $lhs, $rhs",
+                [(ARMcmpZ tGPR:$lhs, tGPR:$rhs)]>;
 }
 
 // TODO: A7-37: CMP(3) - cmp hi regs
@@ -551,7 +551,7 @@ def tSXTH  : T1I<(outs tGPR:$dst), (ins tGPR:$src),
 let isCommutable = 1, Defs = [CPSR] in
 def tTST  : T1I<(outs), (ins tGPR:$lhs, tGPR:$rhs),
                "tst $lhs, $rhs",
-               [(ARMcmpNZ (and tGPR:$lhs, tGPR:$rhs), 0)]>;
+               [(ARMcmpZ (and tGPR:$lhs, tGPR:$rhs), 0)]>;
 
 // zero-extend byte
 def tUXTB  : T1I<(outs tGPR:$dst), (ins tGPR:$src),
diff --git a/lib/Target/ARM/ARMInstrThumb2.td b/lib/Target/ARM/ARMInstrThumb2.td
index 538fcc2..6bcd499 100644
--- a/lib/Target/ARM/ARMInstrThumb2.td
+++ b/lib/Target/ARM/ARMInstrThumb2.td
@@ -607,18 +607,18 @@ def t2REVSH : T2I<(outs GPR:$dst), (ins GPR:$src),
 
 defm t2CMP   : T2I_cmp_is<"cmp",
                           BinOpFrag<(ARMcmp node:$LHS, node:$RHS)>>;
-defm t2CMPnz : T2I_cmp_is<"cmp",
-                          BinOpFrag<(ARMcmpNZ node:$LHS, node:$RHS)>>;
+defm t2CMPz : T2I_cmp_is<"cmp",
+                         BinOpFrag<(ARMcmpZ node:$LHS, node:$RHS)>>;
 
 defm t2CMN   : T2I_cmp_is<"cmn",
                           BinOpFrag<(ARMcmp node:$LHS,(ineg node:$RHS))>>;
-defm t2CMNnz : T2I_cmp_is<"cmn",
-                          BinOpFrag<(ARMcmpNZ node:$LHS,(ineg node:$RHS))>>;
+defm t2CMNz : T2I_cmp_is<"cmn",
+                         BinOpFrag<(ARMcmpZ node:$LHS,(ineg node:$RHS))>>;
 
 def : T2Pat<(ARMcmp  GPR:$src, t2_so_imm_neg:$imm),
             (t2CMNri GPR:$src, t2_so_imm_neg:$imm)>;
 
-def : T2Pat<(ARMcmpNZ  GPR:$src, t2_so_imm_neg:$imm),
+def : T2Pat<(ARMcmpZ  GPR:$src, t2_so_imm_neg:$imm),
             (t2CMNri   GPR:$src, t2_so_imm_neg:$imm)>;
 
 // FIXME: TST, TEQ, etc.
diff --git a/test/CodeGen/Thumb2/thumb2-cmn.ll b/test/CodeGen/Thumb2/thumb2-cmn.ll
new file mode 100644
index 0000000..1f3ef1b
--- /dev/null
+++ b/test/CodeGen/Thumb2/thumb2-cmn.ll
@@ -0,0 +1,25 @@
+; RUN: llvm-as < %s | llc -march=thumb -mattr=+thumb2 | grep {cmn\\W*r\[0-9\],\\W*r\[0-9\]} | count 4
+
+define i1 @f1(i32 %a, i32 %b) {
+    %nb = sub i32 0, %b
+    %tmp = icmp ne i32 %a, %nb
+    ret i1 %tmp
+}
+
+define i1 @f2(i32 %a, i32 %b) {
+    %nb = sub i32 0, %b
+    %tmp = icmp ne i32 %nb, %a
+    ret i1 %tmp
+}
+
+define i1 @f3(i32 %a, i32 %b) {
+    %nb = sub i32 0, %b
+    %tmp = icmp eq i32 %a, %nb
+    ret i1 %tmp
+}
+
+define i1 @f4(i32 %a, i32 %b) {
+    %nb = sub i32 0, %b
+    %tmp = icmp eq i32 %nb, %a
+    ret i1 %tmp
+}