diff --git a/compiler/src/dmd/backend/cgcod.d b/compiler/src/dmd/backend/cgcod.d
index 1d0db13769..f6bdaed4ed 100644
--- a/compiler/src/dmd/backend/cgcod.d
+++ b/compiler/src/dmd/backend/cgcod.d
@@ -2146,9 +2146,9 @@ regm_t getscratch()
  * before.
  * Look first to see if it is already in a register.
  * Params:
- *	cdb = sink for generated code
- *	e = the elem
- *	pretregs = input is mask of registers, output is result register
+ *      cdb = sink for generated code
+ *      e = the elem
+ *      pretregs = input is mask of registers, output is result register
  */
 
 @trusted
diff --git a/compiler/src/dmd/backend/cod3.d b/compiler/src/dmd/backend/cod3.d
index 62b5cb392e..612dd0e835 100644
--- a/compiler/src/dmd/backend/cod3.d
+++ b/compiler/src/dmd/backend/cod3.d
@@ -6491,7 +6491,7 @@ uint calccodsize(code *c)
                 size = 9;               // 64 bit immediate value for MOV to/from RAX
                 goto Lret;
             }
-            goto Ldefault;
+            goto default;
 
         case 0xF6:                      /* TEST mem8,immed8             */
             ins = inssize[op];
@@ -6511,8 +6511,16 @@ uint calccodsize(code *c)
                 size += (i32 ^ ((iflags & CFopsize) !=0)) ? 4 : 2;
             break;
 
+        case 0xFA:
+        case 0xFB:
+            if (c.Iop == ENDBR32 || c.Iop == ENDBR64)
+            {
+                size = 4;
+                break;
+            }
+            goto default;
+
         default:
-        Ldefault:
             ins = inssize[op];
             size = ins & 7;
             if (i32)
@@ -6992,7 +7000,7 @@ uint codout(int seg, code *c, Barray!ubyte* disasmBuf)
             else if ((op & 0xFF00) == 0x0F00)
                 ins = inssize2[op & 0xFF];
 
-            if (op & 0xFF000000)
+            if (op & 0xFF_00_00_00)
             {
                 ubyte op1 = op >> 24;
                 if (op1 == 0xF2 || op1 == 0xF3 || op1 == 0x66)
diff --git a/compiler/src/dmd/backend/code_x86.d b/compiler/src/dmd/backend/code_x86.d
index 0107d28ffa..96aa4f3206 100644
--- a/compiler/src/dmd/backend/code_x86.d
+++ b/compiler/src/dmd/backend/code_x86.d
@@ -464,6 +464,8 @@ enum
 
     ESCAPE  = SEGDS,   // marker that special information is here
                        // (Iop2 is the type of special information)
+    ENDBR32 = 0xF30F1EFB,
+    ENDBR64 = 0xF30F1EFA,
 }
 
 
diff --git a/compiler/src/dmd/backend/ptrntab.d b/compiler/src/dmd/backend/ptrntab.d
index 160ee8763d..34ec577736 100644
--- a/compiler/src/dmd/backend/ptrntab.d
+++ b/compiler/src/dmd/backend/ptrntab.d
@@ -51,6 +51,8 @@ alias aptb0AAA = OPTABLE0!(     0x37  ,_i64_bit | _modax);
 alias aptb0AAD = OPTABLE0!(     0xd50a,_i64_bit | _modax);
 alias aptb0AAM = OPTABLE0!(     0xd40a,_i64_bit | _modax);
 alias aptb0AAS = OPTABLE0!(     0x3f,  _i64_bit | _modax);
+alias aptb0ENDBR32 = OPTABLE0!( ENDBR32, _I386);
+alias aptb0ENDBR64 = OPTABLE0!( ENDBR64, _I386);
 alias aptb0CBW = OPTABLE0!(     0x98,_16_bit | _modax);
 alias aptb0CWDE = OPTABLE0!(    0x98,_32_bit | _I386 | _modax);
 alias aptb0CDQE = OPTABLE0!(    0x98,_64_bit | _modax);
@@ -4933,6 +4935,8 @@ immutable OP[] optab = [
     { "dt",         ITdata | OPdt,  { null } },
     { "dw",         ITdata | OPdw,  { null } },
     { "emms",       0,              { &aptb0EMMS[0] } },
+    { "endbr32",    0,              { &aptb0ENDBR32[0] } },
+    { "endbr64",    0,              { &aptb0ENDBR64[0] } },
     { "enter",      2,              { &aptb2ENTER[0] } },
     { "extractps",  3,              { &aptb3EXTRACTPS[0] } },
     { "f2xm1",      ITfloat | 0,    { &aptb0F2XM1[0] } },
diff --git a/compiler/src/dmd/iasmdmd.d b/compiler/src/dmd/iasmdmd.d
index 1ddd1ba886..a0724c7579 100644
--- a/compiler/src/dmd/iasmdmd.d
+++ b/compiler/src/dmd/iasmdmd.d
@@ -1765,6 +1765,14 @@ code *asm_emit(Loc loc,
 
         case 0x0F0000:                      // an AMD instruction
             const puc = (cast(ubyte *) &opcode);
+            if (opcode == ENDBR32 || opcode == ENDBR64)
+            {
+                emit(puc[3]);
+                emit(puc[2]);
+                emit(puc[1]);
+                emit(puc[0]);
+                goto L3;
+            }
             emit(puc[2]);
             emit(puc[1]);
             emit(puc[0]);
diff --git a/compiler/test/runnable/iasm64.d b/compiler/test/runnable/iasm64.d
index 1883c87387..4fd7879744 100644
--- a/compiler/test/runnable/iasm64.d
+++ b/compiler/test/runnable/iasm64.d
@@ -3718,6 +3718,8 @@ void test50()
         0x9B,           // wait
         0x91,           // xchg EAX,ECX
         0xD7,           // xlat
+        0xF3, 0x0F, 0x1E, 0xFB, // endbr32
+        0xF3, 0x0F, 0x1E, 0xFA, // endbr64
         0x48, 0x8D, 0x1D, 0x02, 0x00, 0x00, 0x00, // lea RBX,L1;
         0x89, 0xC0,     // mov EAX,EAX
     ];
@@ -3844,6 +3846,8 @@ L10:    nop; nop;         // put instructions above this or L10 changes
         wait    ;
         xchg    EAX,ECX ;
         xlat    ;
+        endbr32 ;
+        endbr64 ;
         lea     RBX,L1 ;
         mov     EAX,EAX ;
 
@@ -3853,6 +3857,7 @@ L1:                                     ;
     }
     for (i = 0; i < data.length; i++)
     {
+        //printf("[%d] %02x %02x\n", i, p[i], data[i]);
         assert(p[i] == data[i]);
     }
 }