PP: Fix #1605: Paste tokens for ## through number->letter transitions.

Test/baseResults/cppMerge.frag.out

@@ -0,0 +1,23 @@
+cppMerge.frag
+Shader version: 450
+0:? Sequence
+0:22  Function Definition: main( ( global void)
+0:22    Function Parameters: 
+0:?   Linker Objects
+0:?     'dest1' (layout( set=0 binding=0) writeonly uniform image1D)
+0:?     'dest2' (layout( set=0 binding=0) writeonly uniform image1D)
+0:?     'dest3' (layout( set=0 binding=0) writeonly uniform image1D)
+
+
+Linked fragment stage:
+
+
+Shader version: 450
+0:? Sequence
+0:22  Function Definition: main( ( global void)
+0:22    Function Parameters: 
+0:?   Linker Objects
+0:?     'dest1' (layout( set=0 binding=0) writeonly uniform image1D)
+0:?     'dest2' (layout( set=0 binding=0) writeonly uniform image1D)
+0:?     'dest3' (layout( set=0 binding=0) writeonly uniform image1D)
+

Test/cppMerge.frag

@@ -0,0 +1,24 @@
+#version 450 core
+
+#define PASTER2(type, suffix) type##suffix
+#define PASTER3(type, suffix) type## suffix
+#define MAKE_TYPE1 image1D dest ## 1;
+#define MAKE_TYPE2(type, suffix) PASTER2(type, suffix)
+#define MAKE_TYPE3(type, suffix) PASTER3(type, suffix)
+
+#define PREFIX image
+#define PREFIX3 imag
+#define SUFFIX2 1D
+#define SUFFIX3 e1 D
+
+#define RESOURCE_TYPE1 MAKE_TYPE1
+#define RESOURCE_TYPE2 MAKE_TYPE2(PREFIX, SUFFIX2)
+#define RESOURCE_TYPE3 MAKE_TYPE3(PREFIX3, SUFFIX3)
+
+layout (set = 0, binding = 0) uniform writeonly RESOURCE_TYPE1
+layout (set = 0, binding = 0) uniform writeonly RESOURCE_TYPE2 dest2;
+layout (set = 0, binding = 0) uniform writeonly RESOURCE_TYPE3 dest3;
+
+void main()
+{
+}

glslang/MachineIndependent/preprocessor/PpContext.h

@@ -84,6 +84,7 @@ NVIDIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <sstream>
 
 #include "../ParseHelper.h"
+#include "PpTokens.h"
 
 /* windows only pragma */
 #ifdef _MSC_VER
@@ -213,6 +214,7 @@ public:
         virtual int getch() = 0;
         virtual void ungetch() = 0;
         virtual bool peekPasting() { return false; }             // true when about to see ##
+        virtual bool peekContinuedPasting(int) { return false; } // true when non-spaced tokens can paste
         virtual bool endOfReplacementList() { return false; } // true when at the end of a macro replacement list (RHS of #define)
         virtual bool isMacroInput() { return false; }
 
@@ -263,7 +265,9 @@ public:
                 snprintf(ppToken.name, sizeof(ppToken.name), "%s", name.c_str());
                 return atom;
             }
-            bool isAtom(int a) { return atom == a; }
+            bool isAtom(int a) const { return atom == a; }
+            int getAtom() const { return atom; }
+            bool nonSpaced() const { return !space; }
         protected:
             Token() {}
             int atom;
@@ -276,6 +280,35 @@ public:
 
         void putToken(int token, TPpToken* ppToken);
         bool peekToken(int atom) { return !atEnd() && stream[currentPos].isAtom(atom); }
+        bool peekContinuedPasting(int atom)
+        {
+            // This is basically necessary because, for example, the PP
+            // tokenizer only accepts valid numeric-literals plus suffixes, so
+            // separates numeric-literals plus bad suffix into two tokens, which
+            // should get both pasted together as one token when token pasting.
+            //
+            // The following code is a bit more generalized than the above example.
+            if (!atEnd() && atom == PpAtomIdentifier && stream[currentPos].nonSpaced()) {
+                switch(stream[currentPos].getAtom()) {
+                    case PpAtomConstInt:
+                    case PpAtomConstUint:
+                    case PpAtomConstInt64:
+                    case PpAtomConstUint64:
+                    case PpAtomConstInt16:
+                    case PpAtomConstUint16:
+                    case PpAtomConstFloat:
+                    case PpAtomConstDouble:
+                    case PpAtomConstFloat16:
+                    case PpAtomConstString:
+                    case PpAtomIdentifier:
+                        return true;
+                    default:
+                        break;
+                }
+            }
+
+            return false;
+        }
         int getToken(TParseContextBase&, TPpToken*);
         bool atEnd() { return currentPos >= stream.size(); }
         bool peekTokenizedPasting(bool lastTokenPastes);
@@ -344,6 +377,10 @@ protected:
     int  getChar() { return inputStack.back()->getch(); }
     void ungetChar() { inputStack.back()->ungetch(); }
     bool peekPasting() { return !inputStack.empty() && inputStack.back()->peekPasting(); }
+    bool peekContinuedPasting(int a)
+    {
+        return !inputStack.empty() && inputStack.back()->peekContinuedPasting(a);
+    }
     bool endOfReplacementList() { return inputStack.empty() || inputStack.back()->endOfReplacementList(); }
     bool isMacroInput() { return inputStack.size() > 0 && inputStack.back()->isMacroInput(); }
 
@@ -368,6 +405,7 @@ protected:
         virtual int getch() override { assert(0); return EndOfInput; }
         virtual void ungetch() override { assert(0); }
         bool peekPasting() override { return prepaste; }
+        bool peekContinuedPasting(int a) override { return mac->body.peekContinuedPasting(a); }
         bool endOfReplacementList() override { return mac->body.atEnd(); }
         bool isMacroInput() override { return true; }
 
@@ -442,11 +480,15 @@ protected:
 
     class tTokenInput : public tInput {
     public:
-        tTokenInput(TPpContext* pp, TokenStream* t, bool prepasting) : tInput(pp), tokens(t), lastTokenPastes(prepasting) { }
+        tTokenInput(TPpContext* pp, TokenStream* t, bool prepasting) :
+            tInput(pp),
+            tokens(t),
+            lastTokenPastes(prepasting) { }
         virtual int scan(TPpToken *ppToken) override { return tokens->getToken(pp->parseContext, ppToken); }
         virtual int getch() override { assert(0); return EndOfInput; }
         virtual void ungetch() override { assert(0); }
         virtual bool peekPasting() override { return tokens->peekTokenizedPasting(lastTokenPastes); }
+        bool peekContinuedPasting(int a) override { return tokens->peekContinuedPasting(a); }
     protected:
         TokenStream* tokens;
         bool lastTokenPastes; // true if the last token in the input is to be pasted, rather than consumed as a token

glslang/MachineIndependent/preprocessor/PpScanner.cpp

@@ -96,12 +96,19 @@ namespace glslang {
 /////////////////////////////////// Floating point constants: /////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////////////////////
 
-/*
-* lFloatConst() - Scan a single- or double-precision floating point constant.  Assumes that the scanner
-*         has seen at least one digit, followed by either a decimal '.' or the
-*         letter 'e', or a precision ending (e.g., F or LF).
-*/
-
+// 
+// Scan a single- or double-precision floating point constant.
+// Assumes that the scanner has seen at least one digit,
+// followed by either a decimal '.' or the letter 'e', or a
+// precision ending (e.g., F or LF).
+//
+// This is technically not correct, as the preprocessor should just
+// accept the numeric literal along with whatever suffix it has, but
+// currently, it stops on seeing a bad suffix, treating that as the
+// next token. This effects things like token pasting, where it is
+// relevant how many tokens something was broken into.
+//
+// See peekContinuedPasting().
 int TPpContext::lFloatConst(int len, int ch, TPpToken* ppToken)
 {
     const auto saveName = [&](int ch) {
@@ -435,6 +442,14 @@ int TPpContext::characterLiteral(TPpToken* ppToken)
 //
 // Scanner used to tokenize source stream.
 //
+// N.B. Invalid numeric suffixes are not consumed.//
+// This is technically not correct, as the preprocessor should just
+// accept the numeric literal along with whatever suffix it has, but
+// currently, it stops on seeing a bad suffix, treating that as the
+// next token. This effects things like token pasting, where it is
+// relevant how many tokens something was broken into.
+// See peekContinuedPasting().
+//
 int TPpContext::tStringInput::scan(TPpToken* ppToken)
 {
     int AlreadyComplained = 0;
@@ -1153,13 +1168,19 @@ int TPpContext::tokenPaste(int token, TPpToken& ppToken)
             break;
         }
 
-        // get the token after the ##
+        // Get the token(s) after the ##.
+        // Because of "space" semantics, and prior tokenization, what
+        // appeared a single token, e.g. "3A", might have been tokenized
+        // into two tokens "3" and "A", but the "A" will have 'space' set to
+        // false.  Accumulate all of these to recreate the original lexical
+        // appearing token.
+        do {
             token = scanToken(&pastedPpToken);
 
             // This covers end of argument expansion
             if (token == tMarkerInput::marker) {
                 parseContext.ppError(ppToken.loc, "unexpected location; end of argument", "##", "");
-            break;
+                return resultToken;
             }
 
             // get the token text
@@ -1209,6 +1230,7 @@ int TPpContext::tokenPaste(int token, TPpToken& ppToken)
                 else
                     parseContext.ppError(ppToken.loc, "combined token is invalid", "##", "");
             }
+        } while (peekContinuedPasting(resultToken));
     }
 
     return resultToken;

gtests/AST.FromFile.cpp

@@ -93,6 +93,7 @@ INSTANTIATE_TEST_CASE_P(
         "cppSimple.vert",
         "cppIndent.vert",
         "cppIntMinOverNegativeOne.frag",
+        "cppMerge.frag",
         "cppNest.vert",
         "cppBad.vert",
         "cppBad2.vert",