[Invariant Loads] Do not consider invariant loads to have dependences.

We need to relax constraints on invariant loads so that they do not
create fake RAW dependences. So, we do not consider invariant loads as
scalar dependences in a region.

During these changes, it turned out that we do not consider `llvm::Value`
replacements correctly within `PPCGCodeGeneration` and `ISLNodeBuilder`.
The replacements dictated by `ValueMap` were not being followed in all
places. This was fixed in this commit. There is no clean way to decouple
this change because this bug only seems to arise when the relaxed
version of invariant load hoisting was enabled.

Differential Revision: https://reviews.llvm.org/D35120

llvm-svn: 307907

4 files changed, 4 insertions, 11 deletions

diff --git a/polly/test/Isl/CodeGen/invariant_load_base_pointer.ll b/polly/test/Isl/CodeGen/invariant_load_base_pointer.ll
index 414fa414386..6ec27d1614c 100644
--- a/polly/test/Isl/CodeGen/invariant_load_base_pointer.ll
+++ b/polly/test/Isl/CodeGen/invariant_load_base_pointer.ll
@@ -5,7 +5,7 @@
 ; CHECK-NEXT:    %polly.access.BPLoc.load = load i32*, i32** %polly.access.BPLoc
 ;
 ; CHECK-LABEL: polly.stmt.bb2:
-; CHECK-NEXT:    %p_tmp3 = getelementptr inbounds i32, i32* %polly.access.BPLoc.load, i64 %polly.indvar
+; CHECK-NEXT:    %scevgep = getelementptr i32, i32* %polly.access.BPLoc.load, i64 %polly.indvar
 ;
 ;    void f(int **BPLoc) {
 ;      for (int i = 0; i < 1024; i++)
diff --git a/polly/test/Isl/CodeGen/invariant_load_base_pointer_conditional.ll b/polly/test/Isl/CodeGen/invariant_load_base_pointer_conditional.ll
index 3e9e1a62979..987a3ba49dd 100644
--- a/polly/test/Isl/CodeGen/invariant_load_base_pointer_conditional.ll
+++ b/polly/test/Isl/CodeGen/invariant_load_base_pointer_conditional.ll
@@ -12,7 +12,7 @@
 ; CHECK-NEXT:    %polly.preload.tmp6.merge = phi i32* [ %polly.access.BPLoc.load, %polly.preload.exec ], [ null, %polly.preload.cond ]
 ;
 ; CHECK-LABEL: polly.stmt.bb5:
-; CHECK-NEXT:    %p_tmp7 = getelementptr inbounds i32, i32* %polly.preload.tmp6.merge, i64 %polly.indvar6
+; CHECK-NEXT:    %scevgep9 = getelementptr i32, i32* %polly.preload.tmp6.merge, i64 %polly.indvar6
 ;
 ;    void f(int **BPLoc, int *A, int N) {
 ;      for (int i = 0; i < N; i++)
diff --git a/polly/test/Isl/CodeGen/invariant_load_ptr_ptr_noalias.ll b/polly/test/Isl/CodeGen/invariant_load_ptr_ptr_noalias.ll
index 5ddc7e51ed2..5b84a91b902 100644
--- a/polly/test/Isl/CodeGen/invariant_load_ptr_ptr_noalias.ll
+++ b/polly/test/Isl/CodeGen/invariant_load_ptr_ptr_noalias.ll
@@ -7,8 +7,8 @@
 ; CHECK:   %polly.access.polly.access.A.load.load = load i32*, i32** %polly.access.polly.access.A.load
 ;
 ; CHECK: polly.stmt.bb2:
-; CHECK:   %p_tmp6 = getelementptr inbounds i32, i32* %polly.access.polly.access.A.load.load, i64 %polly.indvar
-; CHECK:   store i32 0, i32* %p_tmp6, align 4
+; CHECK: %scevgep = getelementptr i32, i32* %polly.access.polly.access.A.load.load, i64 %polly.indvar
+; CHECK:   store i32 0, i32* %scevgep, align 4
 ;
 ;    void f(int ***A) {
 ;      for (int i = 0; i < 1024; i++)
diff --git a/polly/test/Isl/CodeGen/invariant_load_scalar_escape_alloca_sharing.ll b/polly/test/Isl/CodeGen/invariant_load_scalar_escape_alloca_sharing.ll
index 2393f950069..212792afd6f 100644
--- a/polly/test/Isl/CodeGen/invariant_load_scalar_escape_alloca_sharing.ll
+++ b/polly/test/Isl/CodeGen/invariant_load_scalar_escape_alloca_sharing.ll
@@ -5,19 +5,12 @@
 ; instead use directly the preloaded value stored in GlobalMap.
 ;
 ; CHECK-NOT: alloca
-; CHECK:     %dec3.s2a = alloca i32
-; CHECK-NOT: alloca
-; CHECK:     %dec3.in.phiops = alloca i32
-; CHECK-NOT: alloca
 ; CHECK:     %tmp0.preload.s2a = alloca i32
 ; CHECK-NOT: alloca
 ;
 ; CHECK:       %ncol.load = load i32, i32* @ncol
 ; CHECK-NEXT:  store i32 %ncol.load, i32* %tmp0.preload.s2a
 ;
-; CHECK:      polly.stmt.while.body.lr.ph:
-; CHECK-NEXT:   store i32 %ncol.load, i32* %dec3.in.phiops
-;
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 
 @ncol = external global i32, align 4