Fix a bug in codegenprep where it was losing track of values OptimizeMemoryInst

by switching to a ValueMap. Patch by Andrea DiBiagio!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181397 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 44 insertions, 0 deletions

diff --git a/test/CodeGen/X86/codegen-prepare.ll b/test/CodeGen/X86/codegen-prepare.ll
new file mode 100644
index 0000000000..e8ee070635
--- /dev/null
+++ b/test/CodeGen/X86/codegen-prepare.ll
@@ -0,0 +1,44 @@
+; RUN: llc < %s -mtriple=x86_64-pc-linux | FileCheck %s
+
+; Check that the CodeGenPrepare Pass
+; does not wrongly rewrite the address computed by Instruction %4
+; as [12 + Base:%this].
+
+; This test makes sure that:
+; - both the store and the first load instructions
+;   within basic block labeled 'if.then' are not removed. 
+; - the store instruction stores a value at address [60 + %this]
+; - the first load instruction loads a value at address [12 + %this]
+
+%class.A = type { %struct.B }
+%struct.B = type { %class.C, %class.D, %class.C, %class.D }
+%class.C = type { float, float, float }
+%class.D = type { [3 x %class.C] }
+
+define linkonce_odr void @foo(%class.A* nocapture %this, i32 %BoolValue) nounwind uwtable {
+entry:
+  %cmp = icmp eq i32 %BoolValue, 0
+  %address1 = getelementptr inbounds %class.A* %this, i64 0, i32 0, i32 3
+  %address2 = getelementptr inbounds %class.A* %this, i64 0, i32 0, i32 1
+  br i1 %cmp, label %if.else, label %if.then
+
+if.then:                                         ; preds = %entry
+  %0 = getelementptr inbounds %class.D* %address2, i64 0, i32 0, i64 0, i32 0
+  %1 = load float* %0, align 4 
+  %2 = getelementptr inbounds float* %0, i64 3
+  %3 = load float* %2, align 4 
+  %4 = getelementptr inbounds %class.D* %address1, i64 0, i32 0, i64 0, i32 0
+  store float %1, float* %4, align 4
+  br label %if.end
+
+if.else:                                          ; preds = %entry
+  br label %if.end
+
+if.end:                                           ; preds = %if.then, %if.else, %entry
+  ret void
+}
+
+; CHECK: foo:
+; CHECK: movss 12([[THIS:%[a-zA-Z0-9]+]]), [[REGISTER:%[a-zA-Z0-9]+]]
+; CHECK-NEXT: movss [[REGISTER]], 60([[THIS]])
+