Adjust the stack pointer after a function call, proportional to the number of

arguments pushed onto the stack.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4922 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/X86/InstSelectSimple.cpp b/lib/Target/X86/InstSelectSimple.cpp
index 65bfb1c7ed8fcd9fdf712b8c38af2f59976b82ac..55bf65b2f58b686024307d37b8176166eca3900b 100644 (file)
--- a/lib/Target/X86/InstSelectSimple.cpp
+++ b/lib/Target/X86/InstSelectSimple.cpp
@@ -393,6 +393,9 @@ ISel::visitBranchInst (BranchInst & BI)
 void
 ISel::visitCallInst (CallInst & CI)
 {
+  // keep a counter of how many bytes we pushed on the stack
+  unsigned bytesPushed = 0;
+
   // Push the arguments on the stack in reverse order, as specified by
   // the ABI.
   for (unsigned i = CI.getNumOperands()-1; i >= 1; --i)
@@ -406,11 +409,13 @@ ISel::visitCallInst (CallInst & CI)
          // then push EAX.
          promote32 (X86::EAX, v);
          BuildMI (BB, X86::PUSHr32, 1).addReg (X86::EAX);
+          bytesPushed += 4;
          break;
        case cInt:
        case cFloat: {
           unsigned Reg = getReg(v);
           BuildMI (BB, X86::PUSHr32, 1).addReg(Reg);
+          bytesPushed += 4;
          break;
         }
        default:
@@ -421,6 +426,10 @@ ISel::visitCallInst (CallInst & CI)
     }
   // Emit a CALL instruction with PC-relative displacement.
   BuildMI (BB, X86::CALLpcrel32, 1).addPCDisp (CI.getCalledValue ());
+
+  // Adjust the stack by `bytesPushed' amount if non-zero
+  if (bytesPushed > 0)
+    BuildMI (BB, X86::ADDri32, 2).addReg(X86::ESP).addZImm(bytesPushed);
 }
 
 /// visitSimpleBinary - Implement simple binary operators for integral types...

diff --git a/lib/Target/X86/X86ISelSimple.cpp b/lib/Target/X86/X86ISelSimple.cpp
index 65bfb1c7ed8fcd9fdf712b8c38af2f59976b82ac..55bf65b2f58b686024307d37b8176166eca3900b 100644 (file)
--- a/lib/Target/X86/X86ISelSimple.cpp
+++ b/lib/Target/X86/X86ISelSimple.cpp
@@ -393,6 +393,9 @@ ISel::visitBranchInst (BranchInst & BI)
 void
 ISel::visitCallInst (CallInst & CI)
 {
+  // keep a counter of how many bytes we pushed on the stack
+  unsigned bytesPushed = 0;
+
   // Push the arguments on the stack in reverse order, as specified by
   // the ABI.
   for (unsigned i = CI.getNumOperands()-1; i >= 1; --i)
@@ -406,11 +409,13 @@ ISel::visitCallInst (CallInst & CI)
          // then push EAX.
          promote32 (X86::EAX, v);
          BuildMI (BB, X86::PUSHr32, 1).addReg (X86::EAX);
+          bytesPushed += 4;
          break;
        case cInt:
        case cFloat: {
           unsigned Reg = getReg(v);
           BuildMI (BB, X86::PUSHr32, 1).addReg(Reg);
+          bytesPushed += 4;
          break;
         }
        default:
@@ -421,6 +426,10 @@ ISel::visitCallInst (CallInst & CI)
     }
   // Emit a CALL instruction with PC-relative displacement.
   BuildMI (BB, X86::CALLpcrel32, 1).addPCDisp (CI.getCalledValue ());
+
+  // Adjust the stack by `bytesPushed' amount if non-zero
+  if (bytesPushed > 0)
+    BuildMI (BB, X86::ADDri32, 2).addReg(X86::ESP).addZImm(bytesPushed);
 }
 
 /// visitSimpleBinary - Implement simple binary operators for integral types...