Update the S0 allocation algorithm in indirect send

bcheng0127 · igcbot · commit 15e12acdf3eb · 2025-09-03T00:09:48.000+02:00
_OS_DESCRIPTION
diff --git a/visa/Passes/SRSubstitution.cpp b/visa/Passes/SRSubstitution.cpp
@@ -772,18 +772,20 @@ unsigned short SRSubPassAfterRA::allocateS0(unsigned short UQNum) {
       if (!UsedS0SubReg.isSet(freeSRSub) &&
           !UsedS0SubReg.isSet(freeSRSub + 1)) {
         find = true;
-        S0Index += 2;
+        S0Index = freeSRSub + 2;
         break;
       }
     } else if ((UQNum == 1) && !UsedS0SubReg.isSet(freeSRSub)) {
       find = true;
-      S0Index++;
+      S0Index = freeSRSub + 1;
       break;
     }
-    S0Index++;
   }
 
   if (find) {
+    if (S0Index >= S0SubRegNum) {
+      S0Index = 0;
+    }
     return freeSRSub;
   }
 
@@ -792,15 +794,14 @@ unsigned short SRSubPassAfterRA::allocateS0(unsigned short UQNum) {
       if (!UsedS0SubReg.isSet(freeSRSub) &&
           !UsedS0SubReg.isSet(freeSRSub + 1)) {
         find = true;
-        S0Index += 2;
+        S0Index = freeSRSub + 2;
         break;
       }
     } else if ((UQNum == 1) && !UsedS0SubReg.isSet(freeSRSub)) {
       find = true;
-      S0Index++;
+      S0Index = freeSRSub + 1;
       break;
     }
-    S0Index++;
   }
 
   if (S0Index >= S0SubRegNum) {

Original file line number	Diff line number	Diff line change
`@@ -772,18 +772,20 @@ unsigned short SRSubPassAfterRA::allocateS0(unsigned short UQNum) {`
`772`	`772`	`if (!UsedS0SubReg.isSet(freeSRSub) &&`
`773`	`773`	`!UsedS0SubReg.isSet(freeSRSub + 1)) {`
`774`	`774`	`find = true;`
`775`		`- S0Index += 2;`
	`775`	`+ S0Index = freeSRSub + 2;`
`776`	`776`	`break;`
`777`	`777`	`}`
`778`	`778`	`} else if ((UQNum == 1) && !UsedS0SubReg.isSet(freeSRSub)) {`
`779`	`779`	`find = true;`
`780`		`- S0Index++;`
	`780`	`+ S0Index = freeSRSub + 1;`
`781`	`781`	`break;`
`782`	`782`	`}`
`783`		`- S0Index++;`
`784`	`783`	`}`
`785`	`784`
`786`	`785`	`if (find) {`
	`786`	`+ if (S0Index >= S0SubRegNum) {`
	`787`	`+ S0Index = 0;`
	`788`	`+ }`
`787`	`789`	`return freeSRSub;`
`788`	`790`	`}`
`789`	`791`
`@@ -792,15 +794,14 @@ unsigned short SRSubPassAfterRA::allocateS0(unsigned short UQNum) {`
`792`	`794`	`if (!UsedS0SubReg.isSet(freeSRSub) &&`
`793`	`795`	`!UsedS0SubReg.isSet(freeSRSub + 1)) {`
`794`	`796`	`find = true;`
`795`		`- S0Index += 2;`
	`797`	`+ S0Index = freeSRSub + 2;`
`796`	`798`	`break;`
`797`	`799`	`}`
`798`	`800`	`} else if ((UQNum == 1) && !UsedS0SubReg.isSet(freeSRSub)) {`
`799`	`801`	`find = true;`
`800`		`- S0Index++;`
	`802`	`+ S0Index = freeSRSub + 1;`
`801`	`803`	`break;`
`802`	`804`	`}`
`803`		`- S0Index++;`
`804`	`805`	`}`
`805`	`806`
`806`	`807`	`if (S0Index >= S0SubRegNum) {`