From 7fef551cb123d9f1956f8ec7a142bd8a63d25fa9 Mon Sep 17 00:00:00 2001
From: "Kevin P. Neal" <kevin.neal@sas.com>
Date: Wed, 16 Dec 2020 14:12:35 -0500
Subject: [PATCH] Revert "Revert "[FPEnv] Teach the IRBuilder about invoke's
 correct use of the strictfp attribute.""

Similar to D69312, and documented in D69839, the IRBuilder needs to add
the strictfp attribute to invoke instructions when constrained floating
point is enabled.

This is try 2, with the test corrected.

Differential Revision: https://reviews.llvm.org/D93134
---
 clang/test/CodeGen/exceptions-strictfp.c | 37 ++++++++++++++++++++++++++++++++
 llvm/include/llvm/IR/IRBuilder.h         | 17 +++++++++------
 2 files changed, 48 insertions(+), 6 deletions(-)
 create mode 100644 clang/test/CodeGen/exceptions-strictfp.c

diff --git a/clang/test/CodeGen/exceptions-strictfp.c b/clang/test/CodeGen/exceptions-strictfp.c
new file mode 100644
index 0000000..6f9e9f8
--- /dev/null
+++ b/clang/test/CodeGen/exceptions-strictfp.c
@@ -0,0 +1,37 @@
+// RUN: %clang_cc1 -triple armv7-apple-unknown -ffp-exception-behavior=strict -fexperimental-strict-floating-point -emit-llvm -o - %s -fexceptions -exception-model=sjlj -fblocks | FileCheck %s
+
+// Verify strictfp attributes on invoke calls (and therefore also on
+// function definitions).
+
+// rdar://problem/8621849
+void test1() {
+  extern void test1_helper(void (^)(int));
+
+  // CHECK: define arm_aapcscc void @test1() [[STRICTFP0:#[0-9]+]] personality i8* bitcast (i32 (...)* @__gcc_personality_sj0 to i8*)
+
+  __block int x = 10;
+
+  // CHECK: invoke arm_aapcscc void @test1_helper({{.*}}) [[STRICTFP1:#[0-9]+]]
+  test1_helper(^(int v) { x = v; });
+
+  // CHECK:      landingpad { i8*, i32 }
+  // CHECK-NEXT:   cleanup
+}
+
+void test2_helper();
+void test2() {
+  // CHECK: define arm_aapcscc void @test2() [[STRICTFP0]] personality i8* bitcast (i32 (...)* @__gcc_personality_sj0 to i8*) {
+  __block int x = 10;
+  ^{ (void)x; };
+
+  // CHECK: invoke arm_aapcscc void @test2_helper({{.*}}) [[STRICTFP1:#[0-9]+]]
+  test2_helper(5, 6, 7);
+
+  // CHECK:      landingpad { i8*, i32 }
+  // CHECK-NEXT:   cleanup
+}
+void test2_helper(int x, int y) {
+}
+
+// CHECK: attributes [[STRICTFP0]] = { {{.*}}strictfp{{.*}} }
+// CHECK: attributes [[STRICTFP1]] = { strictfp }
diff --git a/llvm/include/llvm/IR/IRBuilder.h b/llvm/include/llvm/IR/IRBuilder.h
index 56005b2..6bc5e89 100644
--- a/llvm/include/llvm/IR/IRBuilder.h
+++ b/llvm/include/llvm/IR/IRBuilder.h
@@ -350,7 +350,7 @@ public:
     }
   }
 
-  void setConstrainedFPCallAttr(CallInst *I) {
+  void setConstrainedFPCallAttr(CallBase *I) {
     I->addAttribute(AttributeList::FunctionIndex, Attribute::StrictFP);
   }
 
@@ -1088,16 +1088,21 @@ public:
                            ArrayRef<Value *> Args,
                            ArrayRef<OperandBundleDef> OpBundles,
                            const Twine &Name = "") {
-    return Insert(
-        InvokeInst::Create(Ty, Callee, NormalDest, UnwindDest, Args, OpBundles),
-        Name);
+    InvokeInst *II =
+        InvokeInst::Create(Ty, Callee, NormalDest, UnwindDest, Args, OpBundles);
+    if (IsFPConstrained)
+      setConstrainedFPCallAttr(II);
+    return Insert(II, Name);
   }
   InvokeInst *CreateInvoke(FunctionType *Ty, Value *Callee,
                            BasicBlock *NormalDest, BasicBlock *UnwindDest,
                            ArrayRef<Value *> Args = None,
                            const Twine &Name = "") {
-    return Insert(InvokeInst::Create(Ty, Callee, NormalDest, UnwindDest, Args),
-                  Name);
+    InvokeInst *II =
+        InvokeInst::Create(Ty, Callee, NormalDest, UnwindDest, Args);
+    if (IsFPConstrained)
+      setConstrainedFPCallAttr(II);
+    return Insert(II, Name);
   }
 
   InvokeInst *CreateInvoke(FunctionCallee Callee, BasicBlock *NormalDest,
-- 
2.7.4